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GEOLOGICAL SURVEY I MEMOIR 88 i No. 72, Geological SnuBS Geology ol Graham Island, British Columbia J. D. MacKenxle OTTAWA GovEsmiBNT PmimiiG Buikau 1916 Na 1622 -;*«*• J^ ^ ^\l - ■" = T ■i y. t .E ^ _„^ — ."^ X s ^ ^^1 i' ^ M X ,i 3 1 -1 3 ■r >! S •J? CANADA DEPARTMKNT OF MINIMS How. I'. E. Blondih, Ministkm: R. C. McroNMFi ■ , Uiptrv MiNifTci. (iKOlAHllCAL Hi'UVEY I MEMOIR 88 I No. 1i, GvOLOr.lCAL SeKIE!! Geology of Graham Island, British Columbia BY J. D. MacKenzie OTTAWA Government Printing Bureau 1916 y . 1622 CONTENTS. CHAPTER I. PAGE Introduction ^ General statement 1 Field work j Acknowledgments 2 Area '[[ 3 Means of access 4 History g CHAPTER II. Summary j Summary of previous geological work 7 Richardson's report 7 Dawson'i report g Ells' report jl Clapp's report j2 Summary of present report I3 General geology I3 Economic geology 17 Bibliography I9 CHAPTER III. General description of Graham island 22 Topography 22 General topography 22 Regional 22 Local 23 Detailed topography 26 Queen Charlotte range 26 Northern lowland 27 Central Plateau province 28 Northeastern lowland 29 Muskegs 29 Valleys 30 Coast lines 32 Climate 33 Flora 34 Agriculture 35 Commercial possibilities 36 CHAPTER IV. CSeneral geology 37 General statement 37 PAGE Regional 37 Local 37 Table of formations 38 Description of formations 39 Vancouver group 40 Maude formation 40 Distribution 40 Lithology 40 Metamorphism 41 Structure 41 Origin 45 Age 46 Yakoun formation 47 Distribution 47 Lithology 43 Metamorphism 48 Structure 4g Origin SO Age 50 Batholithic rocks 51 Kano quartz diorite 51 Distribution 51 Lithology 51 Structure 51 Origin 52 Langara quartz diorite 52 Distribution 52 Lithology 52 Structure 52 Origin 52 Diabase 53 Distribution 53 Lithology 53 Structure 53 Origin 53 Age and correlation of batholithic rocks 53 Queen Charlotte series 54 Haida formation 54 Distribution 54 Lithology 55 Stratigraphy and structure 56 Folding and faulting 58 Relation to the Vancouver group 58 Relation to the Honna formation 59 Relation to the Tertiary formations 59 Hi PAGE Honna formation 59 Distribution 50 Lithology 60 Stratigraphy and structure 60 Relation to the Haida formation 61 Relation to the Slcidegate formation 61 Relation to the Tertiary formation 61 Skidegate formation 61 Distribution 61 Lithology 61 Stratigraphy and structure 61 Relation to the Honna formation 62 Relation to the Tertiary formations 62 Metamorphism 62 Structure 62 Igneous intrusions 63 Origin 64 Age ;;;;;; 65 Tertiary formations 66 Etheline formation 66 Distribution 67 Lithology 67 Structure 68 Method of intrusion 70 Age ;.;;;;; 71 Skonun formation 73 Distribution 75 Lithology 73 Structure 73 Origin 74 Age ;:; 74 Masset formation 76 Distribution 76 Lithology 75 Structure 77 Thickness 7jj Method of extrusion 78 Origin 79 Age 79 Comparison of the Yakoun and Masset formations 79 Superficial deposits 82 Glacial drift ^2 Lithology 82 Origin 82 Dawson's description of the Superficial deposits 82 CHAPTER V. PAGE Petrography g5 Introduction gg Maude formation gg Quartzitic rocks gg Calcareous feldspathic argillites gg Tufaceous sediments g7 Slaty or shaly argillites g7 Limestones gg Yakoun formation gg Basalts gg Augite andesite g9 Pyroclastic rocks g9 Basalt tuffs gp Basalt agglomerates 90 Batholithic rocks 90 Kano quartz diorite 90 Langara quartz diorite 92 Diabase 92 Haida formation 92 Coarse quartzose sandstone 92 Feldspathic arkoses 93 Quartz sandstones 93 Tufaceous sandstones and breccias 93 Skidegate formation 94 Sandstone 94 Etheline formation 94 Dacite 94 Quartz bearing andesite 95 Andesite 95 Andesite porphjTite 96 Augite andesite 9g Biotite andesite porphyrite 97 General petrology 9g Alteration 9g Masset formation 99 Basalt dykes lOO Basalt flows lOO Basalt porphy-;te 101 Basalt amygdaloid 102 Quartz basalt IO3 Tachylyte IO4 Basalt tuff 104 Trachyte IO5 Origin of the Tertiary igneous rocks 107 CHAPTER Vr. Structurnl geology, historical geology, and correlation. . . ""no Structural geology Folding "" Faulting ........'.'.'..'. "" Jointing " ' Historical geology Correlation ■* 118 CHAPTER VII. Economic geology. Coal ■'■'.'.'.'.'.'.'.'.'.'.'.'.['.'.'.". "' Honna basin I -jf^ Cowgitz and vicinity ,," Slatechuck creek ,2, Camp Robertson !,i Location Stratigraphic position [" „ Coal openings. .. . Coal seam ]l^ . . 1 '>6 rvotes on mming '" Structure . Camp Anthracite !'?' Location ! Stratigraphic position ,',, Coalseam "° Strur»ure ^^° Yakou.i lake ^.■............. ^^'^ Location !^*^ Stratigraphic position ... Coalseam 't Structure '.'.'.'.'.'.'.'.'.'. ,4 Extent of the coal-bearing horizon '. . . . .,] Yakoun basin '■ Camp Wilson I^'' Location ,tl Stratigraphic position ' " ' , , ^ Coal openings J , , Coalseam "^f Structure '.'.'.'.'.'.'.'.'.'.'. J Extent of the coal-bearing horizon! ! It? Origin of the coal '^ Lignite [ '^^ Location ^^^ 156 vi PAGE Lignite of Slconur. point 156 Origin 158 Petroleum 158 Maude formation 159 Origin 159 Haida formation 160 Ethcline formation 161 Masset formation 161 Lawn hill 162 West coast 162 Tian point 163 Country rocks 163 Structure 163 Occurrence 163 Origin 165 "Ozocerite" 166 Accumulation of petroleum 168 Conditions on Graham island 169 Conclusions 170 Oil-shale 171 Clay 172 Building stone and limestone 173 Gold 173 CHAPTER VIII. Bore-hole records 176 Index 211 Map 176A. Map 177A. Plate I. II. III. IV. VI. ILLUSTRATIONS. No. 1597. Graham island, Queen Charlotte islands, B.C. Scale 4 miles to 1 inch In pocket No. 1598. Southern portion of Graham island, Queen Charlotte islands, B.C. Scale 2 milef. to 1 inch In pocket Bearskin bay and Slatechuck range Frontispiece A. Western part of Skidegate inlet and Queen Charlotte range 181 B. Serrated summits of Queen Charlotte range 181 A. Seal inlet 183 B. Athlow mountain 183 A. Yakoun lake 185 B. Ski. legate inlet and Honna valley 185 A. Hanging valley west of Vakoun lake 187 B. Skidcgate inlet. Table mountain, and Alliford bay . . 187 Summit muskeg on Wilson trail 189 vil VII. A. Tow hill '"'Jgj B. Sand dunes at Skonun point jgi VIII. A. Parry passage from the west [[[][ 193 B. Wave-cut bench, Tian point 193 IX. Pillar rock ._- X. Pillar rock, nearer view .07 XI. A. .Maude argillites on King creek tpg B. Faulted layer in .Maude argillites on King creek., .. '. 199 All. ... Vakoun agglomerates east of Skidegate village 201 B. Andesite dyke on the shore of Bearskin bay . 201 XIII. A. Cross-bedded sandstones of the Skonun formation at Skonun point 20J B. Columnar jointed basalt at Tian point 203 XIV. Skidegate Indian village 20S XV. Hemlock timber west of Honna river 207 XVI. A. "Augenkohlc" from the tunnel of the British Pacific Coal Company 200 B. Spheroidal concretion-like bodies emtjen a scale of 1 inch to 2 miles. ACKNOWl-EDuMENTS. The writer w'shes to express his sincere thanks to the many residents of Gra'aam island who, by their encouragement and assistance, furthered the progress of the work, and especially to Mr. E. M. Sandilands, government agent at Queen Charlotte. Others who have aided include Mr. G. D. Beattie, Dr. and Mrs. J. T. Wright, and Mr. and Mrs. W. J. Smith of Queen Charlotte; Captain S. Ferguson, Mr. Fred, and Mr. Walter DeLisle, Mr. Mallory, and Mr. Van Valkanburg of Fort Clements; Mr. J. M. Campbell, Mr. Henry Edenshaw, Mr. Charles Harri- win, Mr. James Martin, Mr. F. Na»h, and Mr. H. F. and Mr. E. T. VWarmouth of Massi-t. Most of the companies pr<)«f)ccting on Graham island have furnished assistance, anionR them the C.raham Island Collieries Company, the tlraham Island Coal and TinilHT Syndicate, the B.C. Oilfields, Limited, and the Western foal ami Iron Cor- poration, Limited. Mr. Milnor Rolurts, in charge of the developnunt work for the l"»er company, and his assistants Mr. Livingston Wernecke an . .,ir. J. M. Ma(l)on.il.l h.ive beer particularly helpful, both in active co-optration in field work, and by furnishing analyses and other data. Mr. J. H. Dawson,' Surveyor C.eneral of Mritish Columbia, also, has given valuable assistance by furnishing maps, In the preparation of this report, the writer has fre(iuently received advice from the niemi)ers of the C.eological Department of the Massachusetts Institute of Technology, Professors Lindgren, Warren, Shimer, and Lahee. In no wav, however, are they to be held responsible for any of the statements made. .\REA. Graham island is the largest of the Queen Charlotte p lup, and with the exception of L mgara or North island, it is the most northerly. Its total area is about 2,.S00 square n-.iles. The south-central part of the island, comprising the district between Skidegate and Masset inlets, and containing about 300 square miles, was mapped on a scale of 1 inch to 1 mile. The map on a reduced scale of 1 inch to 2 miles accompanies this report. The portions of this area underlain by coal bearing rocks were carefully examined and, outside of the coal basins, sufficient work was done to determine the structure of the under- lying rocks and the absence of coal measures with as much certainty as the outcrops would permit. Reconnaissance traverses were made through Skidegate channel, and up the west coast nearly to Kano inlet; up the east coast to Lawn hill, and thence westerly across the north- eastern lowland to the valley of the Yakoun river. Hidden creek. Ghost river. King creek, and other creeks west of the i Yakoun were also traversed. The shores of Massct and J uskatia inlets were examined, and from Massct a trip was made in a launch westward along the nf)rth coast, and down the west coast as far as Athlow bay. From Dman bay. in the westward part of Massct lake, a reconnaissiuue traverse was maiie by Mr. Dolmage over the trail to Seal inlet on the west coast. MEANS OF ACCESS. The Grand Trunk Pacific Steamship Company maintains a rr-ular service between Prince Rupert and the ports of the Queen Charlotte group. The interior of Graham island is reached by trails, to some degree by the fiord-like inlets which indent the coast, and by the Yakoun river. .... . . From Queen Charlotte a good horse trad leads west about 2J miles to the mouth of the Honna river, which is the starimjf point for expeditions to the southern interior. From the mouth a trail, passable for horses after lon^-continucl dry weather only, and usually too soft for use by pack animals, follows up the Honna river for 4 miles to the so-called Kourmile camp. There thj trail forks, one branch leading to Camp Robertson, the other to Camp Wilson. The trail to Camp Robertson runs northwestward for 5 miles over the easternmost ^purs of the high hills forming the ridge extrnding eastward from Mt. Etheline, a very rough and hilly country. This trail has unnecessarily steep gradients and the many ups and downs make it a trying road to traverse. A much better route to Camp Robertson could be provided by building a trail at the base of the hills just mentioned north- westward to the junction of Falls and Wawa creeks and thence up the valley of Wawa creek to Camp Robertson. This road would have much better grades, and would entail vastly less climbing than the present trail. The trail to Camp Wilson runs almost due north from Fourmile camp for about 5 miles to the Junction where it is joined ..y a trail coming from Camp Robertson. Fron, there the trail continues north and northwestward about 9 miles to 5 Camp WiNon, skirting tht- jasf »h(ir<- <.f Su.' lakr, < nwsinij thf valley of thf TKIl riv.r. an.l pa^sini, thrniiKh tin- l.iry.- tmi>.k.K» on thr sumini' of th» hinlil.m.l lMiw..n ih.il valley an.l |.. ihr >ki(! r.-ad of the C.i ihani Island Co.il .md linilier Syndirate. 'I'his skid road follows a roundabout nuite of aJHiiil M) mil,s to fort Clements on Ma^tset inlet, and a Ir.iil ni ilHUit ih, sinte K ru'lh follows the east l.ank of tlir N'.ikciii river nn.^i nl the distance to the same ;)I,ii r. From Camp Koherison a trail leads west al.oiii ,< mil, - to \akoun lake. Canoes sitvp for iransix.rtalion to the ..pposii,- side of the lake whence a trail leads to Ut -itiell sounleii (reek, coiiiinainK noril. about 2 niije- farther to the southern (di;eof the valley of ( .hi-l r:\.r, v. lure it turns,. i-tward f,,r s,.iiu. f,no yards t,, the ^■akoull ri\< r. 'I'he Yakoun rntr iurnishes a natural miiie to the -..iiiluTn interior of the island na\ iuable at almost all sta:;es ,,f water. The river is passable f(.r canoes and rixiT boats i.. ( .mip \\ ilsun alth,)UKh many lo^-jams obstruct tlie passage. It the iam- were wholly removed, the river would be nav ii;able to its soun c in Vakoun laki'. The west coast m.iy l>e reached from the iiortlicrii end ol the island by vMsoJin,- launches, ,.r by a trail leading from X.iden harbour to ( )t.ird bay and thence to li.m head. Vr m the head of Din.m bay, on Masset Like, a- tlu- lar^c inland .Np.Misi.in of the inlet is termed, a trail ic.ids southw.ird .ibout t nilcs i,, Seal inlet on the west co.isi. (hviPK to the thick lover of wet moss and decawd vegeta- tion, the trails ,ire seldom in good condition. Weeds and under- brush obstruct die pathways, and the soft and inscure footing, the roots, snags, ami bog-holes make rapid 'r.ivelling an imixis- sibility. After a lew days of ran. a trail that is being usi.l nuich becomes litth- better than a tlitch; and carrying a pa( k under these conditions is most burdensome. The distance from Camp Wilson to the mouth of the Honna, about 18 miles by the trail, M is mKIoiii r(i\ir<-(l in liss than si\tn li. irs witliinit packs; and packers carryini; only 40 to 50 pounds miuirc two days for the trip. '1 lu'^c oli-t,ii lis make sur\t\inj; or prosptctinj; slow and costly. iiisrc^KV.' The Oim n Charlotte i-l amis named hy Dixon in 17S1, wero visited liy se\iral Spani.-h e\pedition.- .it »Mrlier dates, h i-, possible di.il ihey were vi-iled a^ e.irly as 16,?'; by the Spani.ird li,u-|h(.liime\\ he lonte, who coininanded an e.xpedilion fiited out at Callao, rem. Ihe tirst wdl authenticated \ i.Mt seems to have been tli.it ol llnsign Juan Perez, who reached the islands on July IS, 1771. Alter I'erez, the group was visitefl by Hodega and Maurellein 177.=i;I,a I'erouse, I.owrie and ( uiise, II,inna,and I'ortlock and Dixon in 17^6; Dixon, and Colnett and Duni.in in 1787; Duii'-.m. and Doii-las in 17S,S; Cray, and Funtcr in 17M9; Ingrahani, and March.ind in 1791: Jacinto Caamano. Haswell, (.ray. and X'aiicoiiver in 1792: .md Vai ouver in 179,i. Various fur-traders coiiliniied to visit the islands, but on the decline of the fur trad( , attention was (to (|uote Dawson) "witli.lr.iuTi from tlir i.slands until I,H,S2, when the Hiulsnii Buy Comp.iny dispatclie.1 a |.,irty of men in the- Urij; I na, Captain Mitchell, to discover the locality from which several siiecinicns of koI.1 had l»;en l.rounht by Indi.ms. 'lhi> ua~ loimd to he in I'ort Kii|«r or Cold Harliour, on the wist co.ist. '1 lu yold w.is found in a small irremil.ir vei.i. which was soon proved to run out ill ever>- direction The enterprise was soon akind-ned, but the discovers- lor a lime ce.itecl c|iiite ,\ furnri — the first gold excite :iieiit of llrilish filcmlii.i- ,,iid the locality was visited by .i numbc-r of miners, but with no lie Iter success Mr. Downie (in l.><.^'» apiie.irs to have been the liisl to discv, r the cdal at Skidegate inlet. Afxiiit this time a C, plain 'lorrens .ilso went with i |urty to prosiH-ct on the Qm;-» Chirlolte islands, and n.iridwly e.sc.i[K-.cl nias.s,icTe by the Skide:,;ate Indians." Wirious surveys of inlets and h.irbours were made by ot'tici is of the Roy.d .\,ivy, fnini ISF,2 to 18S6, when !>. I'endet-, R. N., made a careful chart of a large portion of Skideg.Ue inlet. I lor a more- H.'tuil«l account of tin- c-.irly viiy^K'-n of discoTiTy to the Quoa Clliirlntt.- isLiiids, see Ujwso:i. C. .M., (kHil. Surv., Can., kept, of Prog., m;H-7iJ. pp. JB-l^B, fiuiii whu ii this acicmiit i.s trob- ably a carbonaceous layer in the argillites was mistaken for a weathered coal scam, a mistake that might easily be made. ' Rlcharilson. Jamw. Gt^ol. Oarr.. Can.. Rent, of Proa Apptndice*. ^" 187J-7J, pp. S6-A3 and '...jmm The iron ores, mentioned by Richardson as occurring in the "Lower shales," are probably concretionary bands of doiomitic and calcareous shale, which are sufficiently ferruginous to weather bufi and brown. Appendices to his report deal with the fossils collected, coal analyses, etc. Dawson's report'. The report by G. M. Dawson on the Queen Charlotte islands, in so far as it deals with Graham island, is based on a careful examination of the shores and islands of Skidcgate inlet (of which a map on the scale of 1 inch to 1 mile accompanies the report), an examination of portions of the cast and north coasts of the island, and a short reconnaissance in Masset inlet. With the exception of the detailed work done in Skidegate inlet, the field w. --k was of an exploratory or reconnaissance nature. The scope of the report may best be indicated by giving the titles of its main divisions. These are: Position, discovery, and early history of the islands. General description of the islands. Geological observations. General remarks on the rocks of the Queen Charlotte islands. Notes on the map. Triassic. Cretaceous coal-bearing rocks. Tertiarj-. Glaciation and superficial deposits. Th liscovery and early history of the islands have already been summarized in the present report. The general description of the group deals with their geography, topography, and scenery, and is a valuable contribution to the knowledge of the islands. Dawson's map, accompanying his report, ren 'ned until very recent years the only reliable general map of the group, and parts of the west coast are to this day as little known as when his visit was made. ^The table of formations given by Dawson is as follows: ' Dawson, G. M., Geol. Siuv., Can.|AnD. Kept.. 1878-79. pp. 1B-239B. mmmmmimm mam Post-Pliocene, f Sands and gravels. \ Plastic and boulder clays, etc. Unconformity, with evidence 0/ some flexure and disturbance of Tertiary beds. Tertiary, probably Miocene. Volcanic rocks of the north part of Graham island. Sandstones, with marine fossils and lignites of Skonun ix)int. Shales, clays, and lignites of Mamin river and Chinoo- kundl creek. Complete unconformity, with evidence of ^reat disturbiinre of mountain making. Chief period Cretaceous. .\. I'ppcr shales and sandstones. B. Coarse conglomerates. C. Lower shales and sandstones. D. .Agglomerates. E. Lower sandston^is. Triassic, but possibi)' pass- ing lx;low into Car- boniferous. Vnconformity, tut Zfithout evideme of great disturbance. Agglomerates and ash rocks o. ' ogan inlet, etc. (These possibly rc|)resent subdivision D., supra.) Flagg>- calcareous argillites and thin limestones. Massive limestones. Massive dioritic and feldspathic volcanic accumula- tions, probably including minor limestone beds, [ occasionally schistose. A comparison of this table witli the subdivisions used in this report is given on page 11. The rocks called Triassic I)y Dawson, include limestones and black, calcareous, flaggy argillites, and he mapped a small portion of the south side of Maude island as bcwv underlain by this formation. These rocks, together with < '.ner rocks of Skidegate inlet, erroneously supposed by Dawson to be Cre- taceous, have been shown through fossils collected by the writer to be lower Jurassic and perhaps Triassic in age, and are termed in this report the Maude formation. The Cretaceous rocks of Skidegate inlet are described on pages 63B to 77B of his report. Dawson accepts Richardson's subdivision, to which he adds two members, his complete section being: 10 Formation. Thickness. A. Upper shales and sandstones 1 , 5(H) feet. B. Coarse conglomerates 2 , 000 " C. Lower shales with coal and iron ore 5 .000 • D. Agglomerates 3,500 * E. Lower sandstones 1 ,000 ? " 13,000 • This subdivision is not entirely correct, as there is a marked unconformity, structural and paLi'ontological, between sub- division C and subdivision I). A, B, and C arc Upper Cretaceous in age, D and E are middle and lower Jurassic respectively. That such a minute observer as Dawson considered this uncon- formity "essentially unimportant" is largely due to the fact that the Cretaceous and pre-Cretaceous beds are in many instances lithologically similar. This is so much the case, that only by the closest attention to the stratigraphy and structure, and h) care- ful labelling of each collection of fossils, was the present writer able to separate them. Dawson, on r'-'-uctural and lithologic grounds, mapped several areas ^' _.ie-Cretaccous rocks as Cretaceous. The fossils collet . irom beds that he supposed to be wholly Cretaceous, on examination proved to be partly referable to the Upper Cretaceous, and some species to the Jurassic. This conditio of affairs caused uncertainty in regard to the age of these rocks, which were, until the present examin- ation, supposed to be Lower Cretaceous. It has been mentioned that Dawson considered the uncon- formity between subdivisions C and D to be "essentially unim- portant." His conclusion was largely based on an examination of the rocks of Alliford bay, which are shaly and tufaceous sand- stones, quite similar to those occurring in the Cretaceous. On the east side of the bay an apparent transition between true volcanic tuffs and sandstones occurs, rnd is figured by Dawson on page 68B of his report. The writer made a careful study of this locality, and fortunately found abundant fossils in the rocks of Alliford bay, which prove them to be wholly Jurassic. Dawson was right, therefore, in saying this unconformity was unimportant, but he did not recogiiize the much greater and more 11 important unconformity ahove the rocks of Ailiford bay, which, as a matter of fact, are low down in the middle Jurassic . Apart from the misinterpretation of the structure and stratigraphy above referred to, 1 )awson's report, as far a- the writer coulfl check it. is (|uite accurate in the descriptions of the formations; and his deh'neation of these form.itioiis on the map is also excellent. The relations of his subdivisions to those used in this report are gi\en in the table below: Present subdivision. Dawson's suUlivision. I'pper Crc- Skidfsatcform.ition ( A. fppcrshalos and sandstones •j Honna taceous ^ Haida I U. Coarse connloineratcs. , C Lower shales Unconformity. Middle Jurassic Lower Jurassic Vakoun formation .. )'^Llude formation. . Cretaceous D. Agglomerates K. Lower sandstones. Eighty-six pages of Dawson's report are taken up with appendices describing the Haida Indians, the natives of the Queen Charlotte islands. This is a most interesting and readable account of this race which is superior to most if not all of the North Ame:---an aborigines. Plate XIV illustrates the character of one of their villages. ELI,S' RKPORT. In the summer of 1905, K. \\ . Ells of the Geological Survey made a reconnaissance of Graham island. He traversed the shores of the island completely in a sailing boat, and his assistant 12 ascended Yakoun river to Yakoun lake, and crossed thence by trail to Skidcgate inlet. Thus the examination embraced only the coast-line, and one traverse across the island. Two maps accompany the report', one of the whole island on a scale of 1 inch to 4 miles, and one ol a portion of southern tlraham island on a scalf of 1 inch to 1 mile. Owing to the incompleteness of the information available these maps are far from acurate. \-Ai> divided the njcks found on (Iraham island under four heads: I. II. III. 1\. I'ost Tertiary: iiuludinR sands, Kra\i'ls, an;c (K-posits ecting for jjetroleum. > Clapp, C. H., Geol. Surv.. Can., Sum. Kept., 1912. 17 The Ttrti.iry rnrks have het-n Hefnrmcd to fiomf extent, and loc.illy dip at hv h anRles. Surface formations on (Iraham inland consist of (;lacial stratified drift, till, and allu\iiim. (her larRc are.is the bed- rock is deeply f)urie(l, n ndering ihe (teciphcriiiK of the structure difficult. ErnsoMic r,i:oi.ohal(', anee!i pro-perted at Cowgitz and in the Slatechuck v.dley on Skidegate iiilit; at Camps Robertson. Anthracite, Trilby, and Wil-on, and near Vakoun lake, all in the interior. On Skidegate inlet the seams dip at high angles and are much disturbed and the measures .ire intrud»'ns are found near '^^'ikoun lake, where the coal is ,i!ho altereil. At Camp Robertson the coal is well exjjosed in se\er.d prospect openings. One seam is found, which is foliied and faulted in such a way that previous investigators have sup[)osed that two or three seams existed. The maximum thickness of this seam is nearly 9 feet, and the maximum thickness of coal it contains is ,< feet lOj inches, in several bands. The coal is hard and black, and is a low grade bituminous variety, high in .ish. The horizon of the seam extends fiver a considerable area south and west of Camp Robertson, but some fiarts oi this are.i may not contain coal. At Camp .Anthracite south of Camp Robertson, the same seam is also exposed. At Camp Wilson the best .seam of the district is exp»h. I.innitf fKTurs in numiTou.s Mjamsi at Skonun point, and at othtr i>lici<< on the n«.rth and east coasts, ft i, very toii^h and wcjands of the Haiila formation on Maude island. (;o<«| limestone ii found in abutidance at the southeast end of S>uth island. The bituminous rock;* of Graham island have attracted considerable attention of late years, and ho|)es have been en- tertained that extensive p«'trolcum dei)osits would be eventually discovered. These hopes are not justified by the nature of the occurrences found and later in this rejjort will a[)pear the rv;asons for believing that, in npite of apiparcntly favourable indications, Graham island can scarcely be looked to as a future petroleum producer. The source of the bituminous matter is the organic matter of the fossils found in the Maude formation, of lower Jurassic age. Black, tarry material is also found in Tertiarj u>kt^ nd bi>alt flows, Usually in the form of amyndules. It al>o leaks into seams and veins in the basalt, Kiving rise to tar seepages. There is iio reason to suppose that these occurrences indicate a body of licjuid jKtroleum at depth and, furthermore, the structure of the rocks is against such a possibility. It is possible that some of the finer bands of the Maude formation will prove to be oil-shales (jf value. Gold is found on the Southeaster and Beaconsfield claims near Skidcgate Indian village, associated with sulphides, in a quartz gangue. It is also found on the east coast of the island in beach placers. BIBI.KKiRAPIIY. Till' f(i||()win« li>t. llinii^;li lint ( "iiiplctc, onit.iin- the n itms of itic mii-t import, int imhli ,ii(,iiv .li.ilin^ with thf nimn Chailuttr i^l.itvls. Mining; ,> ti,tif .in;foInuicil nconnais^anif <)n (■■ranaiti i-Iand, niUTii I'harloti.' kiroiip. JJ.C." Ciol. Surv.. I an., Sum. Ript., V>\2, pp. lJ-4(). ("lapp, C. II. -"Soiithirn Vancouver M.md." Ccol. Snrv., (ail., M(ni<.ir IJ. l'M2. p. M. Clapp. (". II. -"The coal fulilH of the (Juwn Charlotte i-Linds." Co.il Resources of the Worlil. Twelfth Iiitt r. Ceo. Coiik., I'M.?, f.f. 51.^.S15. Dawson, V.. M.— 'Queen Charlotte inlands." C.eol. Snrv,, Can,, Kept, of Prog., ls7H-7'>. pp, 1M-2.?<;B; with ,ipp. lulix C, by J, F. Whiteavcs, ■t.)n some marine inverlelir.it.i," p[). 1<>()H-J().SH.; apiKiidix I), Notes on eru^'tare.i," liy S. j. Smith, pp. 2(l6M-21.sn; appendix L, "i,il,ind. Queen Charlotte islands, B.C." Trans. Roy. Soc. Can., sec. 2, 1891, pp. 4.S-.S9. MacKenzie, J. I).— "The Queen Charlotte islands." Science Conspectus, Mass. Inst. Tech., Boston, vol. iv, 1914, pp. 14-2.?. C.eol. Surv., Can., Sum. Rept., 191,?, pp. 34-54. Geol. Surv., Can., Sum. Rept. 1914, pp. 3^-^~. Marshall, T. R. — "Coal and iron deposits on Graham island' Queen Charlotte group." Rept. of Minister of Mines, B.C., 1902, pp. H54-H58. 21 C)?,t;(i<)(l,\\'.ll.--"N.itiiral liisti)r\ 'if llicniacti Cli.irlotti' i-l.inds.' I .S, Dtpt. Ill' Ai^riiulliiit-. Noiili Aiiurii.m I'aim.i, NO. 21. \Vasliinj;l(in, i ».("., I'Jdl. r(M>lc, Francis.- -'"Oiicin Cliarliatc i-laml-." I.cm.lon. Hiir^t and r.lackftt, IS".'. Rii liard-nn. Jam -. - "('n.il-': ■,.■']: •. rm k- m|' ilu' ' )arrii ( 'harlcl te islaiiil-." ■ )' Sia-',-,, ( II., l\rpl. n\ I'r.'j;., 1S72-7.', pj). .^O-O.?; v'.'i aiiura 'ix I, ]i'I1. "i »a the lo.-sil plant-." pp. (HI-,;;; .1 )|)rn(li\ II, |-.. liiliiiv^-, "t >ii tlio Mesdzoii- |M->il>," pp. ri-7,S; .ippi'inlix I II, 1;. J. 1 laiTii;.,lnn, "Oil thr aiiahx-s ol' tlu' cua!-," |ip. 7f)-S,<: appmili^ l\', "('iip\- ul ( i.rroiPMinli.iKc nlat'iv; in thr .mtlir.iciic c.f tlu- Oiuin (.'h.irlnltr i^■laIl(l^, ' p|i. S4-S(). S!u!ili>n, Cluiilt^. — "The ilii-i\c carilKiu <>i the ( luct n I'liaiintte island-." In "Tin \\i!driiu-s of tlu- iiorlli I'ai ilic cowt inlands," puMirlud l.y Cliarlr- Si lalnuT's Si,n-, .\<'\ NOrk, l'M2. Sw.in. J. ( ;.- Sniit!is(ini,in i-cntrilmiinns Im kii(i\\l<(|;j.', \ol. 21, Washinutdii, D.C. \\'!iit(M\fs, J. I". - "( )n sdiiM- iiuiTliliratcs fnmi the i( .a!-! 'raring; reck- n\ till' (JiicMi I'liarloll.- i-lands." ("dllri U.i l.\- Mr. Janus Ri. h.irdMiii in 1S72; (ax.l. Siir\ ., Can., Mir.ozi)ic fns-ils, viij. I, part I, lS7i), \i\). \-')l. W'hitcivc-., J. I.- '( )n the f,i-sil- of tin- CLddprarin- deposits of lla- nik-iii Charlotte i^lands. Collerud 1>\- Dr. C.. M. I'.iw^on in 1.S7S." C.e..l. Sim\ ., Can.. Meso/oir fos-il:^, vol. I. i)art III, l^Sl, pp, l<)l-2()2. W hite,i\es, J. I<'. — "On some additional or imperfeilK' nnder- stood fossils trom the' Crelai eons roeks of tlii.' (jiiei'ii Ch.ar- lotte i.-lanil-, with ,1 revised ii-t of speeies from lliese nieks." C.eol. Snrv., Can., vol. I, pari l\", I'Ml), \i\). 26.i-,H>7. 22 CHAPTRR III. GENER.\L DESCRIPTION OF GRAHAM ISLAND. TOroC.RAFHV. C.I-.NIkAI. )()l'0(,K.\l'HV. Rei^ionol. The Ouc.n Cliarlotti- islands form pari ot one of the outer, largeK- siil.mcrgecl ranijcs of the northwestern Cordil- lera, and are generally considered to he the northern rontinu- ation of the \'ancou\(T range. The general trenfl of the islands, which l)ends from about north 40 degrees west in the southern part to more and more nearly due north in the northern portion, if continued northward would bring them into line with tin- outei^ islands of the Alexander archipelago. The pre-Tertiarv axes of folding, however, whic h determined the .general configuration of the coast ranges, are not thus bent. The apparent continuity with the northern ranges is caused by the di-cordance of the axes of folding of the Tertiary rock> of ( iraham island with the earlier axes. Tiie group is separ.ite.i from the mainland by Hecate strait which is M) miles wide at its northern end and w-iden> to 80 miles at the south. Frf>m the i.sl.mds of the Alaskan pan-handle on the north, the group is separated hv Dixon entrance, with an ax ■ rage width of 40 miles. The Queen Charlotte i.slands form a slightly curve.l triangle, shaped like the truncated end of a crescent, convex toward the Pacific, with its apex to the south. The length of the tri.mgle in a northwesterly direction is about !<;() miles, and the wi.lth of its ba.se, the northern ( oast of (iraham island, is about 55 milt-s. The eastern side of Graham i.sland is low and r,,niparativelv straight, but the southern isl;mds of the group are high and ruggiMl. with a deeply indented, liord coast-line. The gently convex western coast-line of the group is more regular than the eastern coast-line, but is indented by .several sinaller fiords and inlets. Two of the.se water wa\s cut across the group, Houston Stewart channel sei)arating Kunghit, the southernmost island of anv considerable 2,? size, from Moresby island; and Skidegate inlet and channel, separatin'j; Moresby and Graham islands. The southern islands lie whol! in the mountains of the Queen Charlotte range which crosses Skidcgate channel and forms the western mountains of Graham island. s\o R T A C R N )v''Z'A 1 i O iV L\f NO \ j^ > c ^1^. ^. ; V //pfj I \'\'- \ 5cs-'«' c' -^ -PS Cf^.'jjt'C^/ 5i.^vyy Csnar'rj 1 ^<^ It* /, . . '=-.7 *o ^f J ti> y / rigure 1. ToiK)graphic provinces, Graham island, B.C. Local. Graha'^ ind may be divicied into four topographic provinces, each well dehned but to some extent gradational into 24 the adj.iinint; ones. These are: the Queen Charlotte rarije, the Central Plateau pro\ince, the Northeastern lowlands, and the Northern lowland. These topoj;raphical divisions will be described separately. Their Ixjundaries are shown in Fi,'ure 1. The Oueen Charlotte range (Plates 1,11, and III) l.,rms the mountainous western portion of the island. These mountains ■• onsist of a .series of pre-Cretaceous nutaniorphir and volcanic rocks, with small areas of inlr'i>ive pkitonic rocks anrj perhaps occasional basins of v relaceous sediments, together with over- Iv.ng Tertiary volcanics. This conii)lex is carved into rugged peaks and ridges, in many |)l,ices serrate, though not as a rule needle-like, and with many very steep, precipitous slopes. Many of the slopes and some of the sununits are glaciated, but glaciation does not appear to have been extensive abf.\e the ,>,000-foot level. A distinctive feature of the range is the cuest.a-shaped peaks, especially prominent in the northern portion, and caused b>- genth- northwestwaid dipping sheets of Tertiary volcanic rocks. The range is partly cut acro.ss by .several of the west coast fiords, also by the valleys of Yakoun lake, l^ockoun river, Hidden creek, ('.host river. King creek, and other creeks and rivers. The rangi' becomes lower in the northern po a'on where its height probably does not exceed 2,000 feet, and nowhere on Graham island is the elevation greater than .^,.500 feet. Fringing the Queen Charlotte range, and lying between the mountains and the Northeastern lowland, is the second topo- grai ■' division, termed the Centra! Plateau province. Starting at the mouth of Slateci.uck creek at Skidegate inlet, the boundary between the mountains and the Plateau province swings north- eastward and northward around the eastern Hanks of the Slate- chuck range, of which Slatechuck mountain is the highest point, and continues in a general northerly direction to the middle of township 8. Near this point the boundary between the Central Plateau province and the northeastern lowlands meets the Queen Charlotte range. This boundary runs east to the eastern part of township 7, whence it tuins sharply southeast, reaching the east coast of the island midway between Dead Tree point and Skidegate Indian village. The Central Plateau province is underlain largely liy basins of relatively >ift, Cretaceous s^ediments, sei)arate(l by hia;her ridges of pre-Cretareous metamorphic and volcanic rocks. The name i)Iaieau is given to the di\ision l)ecau.-c this part of the island — the south-central- -is characterized by a number of hills, from 1,000 to 1,500 feot higii, with a uener.d accordance of summit le\(l, scimc of thi'm tlat-tnpped ridges, others plateau- like, as illustrated in Pl.ites I\' ,ind \'. These higher elevations are composed of the pre-C"retaceous rocks, or, rarel* , of tb- more resistant Cretaceous beds, and are separated liy wide vallevs carved from the more easily denuded t''etaceous sediiiu'nts. It thus happens that many of the topographic d(!)res>ioiis are underlain by geologic basins. Skidegate inlet and the Honna valley, in part, are instances of such depressions. From the middle of township 8, the boundary of the Queen Charlotte range passes northward through the entrance of jusk.itla inb't, crosses Masset inlet, follows up the Am ri\cr, and, curving west- ward around the head of Naden harbour, reaches the west coast about 6 miles north of Frederick islatid. It is thus apparent that the Queen CMiarlolte range doe;, not reach the north coast of Ciraham island. This northern portion, west of Naden harl)our, is termed the Northern lowland, and is chietly imderlain by iVrtiary basalt and pyroclastic rocks, with pre-Cretaceous rocks occurring in the northwestern corner. The Northern lowland (Plate \'I II A) has no elevations exceeding 500 leet, although the surface is hilly and irregular. The .N'orthe.intern lowland i- a striking feature of C.raham is'and, compri.-ing the district ca-t ami northea-t ni tlic [irov- inces just descriln^d. It i> underlain largely by [),irtially or wholly unconsolidated sediniei'ls of Tertiary age, with some areas of younger Tertiar\- \-olcanics, forming flat-to[)pe(! hills. .Apart from these the district is a low, genth undulating plain, densely forested, except where nuiskegs, which are of C((nsider- able total area, occur (Plate VILA). 26 nF.TAII.ED TOFCXiRAPHY. Queen Charlotte Range. In the southern part of Graham island, the Queen Charlotte ran^e consists of a series of very ruKRed peaks and ridges, many of which, in spite of their steep slopes, are densely tree clad to their summits. The Slatechuck range, part (,l the Queen Charlotte range, forms a steep ridge, extending northward between the Slate- chuck and Honna valleys, from Skidegate inlet to Vakoun lake. The highest elevation on Crahani isl.md, Slatechuck mountain, 3,280 feet, is the summit of the Slatechuck range, which is carved from nearU horizontal hcdrjed \oleanic flows flMate I). The higher [jortions of these mountains have lieen modified by the erosive action of local glaciers, a feature which is well shown on Slatechuck and Ktheline mountains. The sh.irp i)eak of Slate- chuck mountain is an important topographical fiature, as from it radiate divides controlling the drainage of south-central Graham island. Scenically, it forms the tlominating feature of the Queen Charlotte range as seen from Skidegate inlet and from its summit a wonderful vie\i- may be obtained over almost the whole of Clraham island and a large part of Moresby island. Very steep mountains, with many ncedlc-like summits, carved from massive granodiorite, ovr-look Cartwright sound and Kano inlet. Owing to the excessive moisture on the west coast, these peaks are verdure clad except on sk-pes closely approaching the vertical. The inlets of this part ot the coast are very steep walled noticeably steeper than those carved in less hard and massive rocks— anrl landings can in many cases be made only where one of the torrential streams, whidi cascade from the hills, has built a delta of angular blocks of the country rock. The lowering skies, with mist shrouding the hill tops and the heavy and long rains intensify the inhospitable nature of this part of the island. This is accentuated by the roar of the heavy surf, reminding one, even when in the calm waters of a fiord far inside the breakers, that travel along this coast is entirely dependent on the weather. 27 North of Ri-nnell sound the Queci) Charlotte range i> almost wholly underlain by Tertiary volcanir ro( k^ and many eiie>ta- shaped peaks are formed. The mountains are not -.o riiRned as those farther M)Uth, and a Lirge number of the mountain tops are hare. Man\- of these hare summits are rounded as if hy i^l.uial action (Plate I II 15); hut on examination it i:- ^een that another process is the cause of their ^uhdueil character. I'.ver\\vhere aliove tre line, which varies in elevation although usually over 1 ..<{)(> feet, the summit'^ are mantled with an accumulalion of sh.irnlv angul,<.r fragments o; the basalt ami hard tuffs which form the hills. These fraf^ments are fro;.-. ] inch to f: inclus in -ize. but ;iveraKe about ^ inches, and in sh.ipe remind one of the s|)alls of rock seen in a stone cutter's y.ird. The climatic condition^ are such that the mist-wreathed ;md rain-drenched hills at this elev.ition ;tre subjected to ra[)id and frequent alternations of freezing urface of the ridees become filled with accumul.itions of the>e angul.ir spalls of rock. The slopes k.iding to the hollows pn sent a curiou^K- strtakcd ap- pearance, due to the clas^if\ing action of moving water on the loose mass of rock fragments. The effect of this process is to smooth out the irregularities of the -urface by breaking down the projections and depositing the debris in the hollow>. The rounded contours of tlu crestlines and hill tops is the result. The process is in effect a phase of what had been called ecmi- planation' by Cairnes. y,orthcni Loidaiul. About 6 miles north of Frederick island, the Queen Char- lotte range, which to this point has fringed the west coast of Graham island from Skideg.ite inlet, rather abruptly loses its mountainous character, and is continued, if the term he per- 1 Cairnes, D. D. Bull. Geol. Soc. America. Vol. li. IHU. pp. 3iJ-318. 28 misiibic, in thr Northern lowland. This topographic Milxii- vision extends northward over the remainder of (iraham islan.l, west of Naden harlu.ur, and also over l-angara i>land. It has been observed by the writer from the sea only, but it is a district i haiarterized by low ridges, none over 500 feet, and it is said to contain numerous larj^e, o|)en muskegs. Central J'latcait Province. From the summit of Mount l.theline a good view may be obtained of this province; and its e.xtenial relations, already described, may be seen. The [.iateau-like character i> not at first ai)parent; i)ut clo^r inspection shows a striking accordance in the levels of the hill tops and ridges. This plateau surface extends sonthwanl .icross Skidegate inlet and is visible on the northeastern part of Moresi)y island, where Table mountain, and other ilat-toiJiied hills reach its level. The elevation of the hill tops is not strictly uniform, but varies from 1,000 to 1,500 feet. It seems probable that this general level represents a surface on which there was an approach to basc-le%elling, after the uplift which followed the deposition of the Tpper Cretaceous >ediments; but nothing more even than a rolling surface, or perha|)s a lowland surmounted by low monadnocks, was developed. On this surf.ice were iioured out the floods of Tertiary lavas which were erupted after a period of tiyke and sill intrusi..n. Although the lavas have .since been largely denuded from the south-centr.il part of the island, the caf) on Mount r.enevieve indicates that they once extended some distance eastward from their pre:,ent iJo.-ition in the Slatecjuck nnge. East of the Honna valley, a flat-topped range of hills extends northward from Skidegate inlet. Behind Queen Charlotte these hills are 1,200 feet high and they gradually rise, until, east of Camp Wilson, they are about 1,800 feet high. This ridge is cut i.cross by the valleys of Skowkona creek, a large tributar\' of the Honna, and by the headwaters of the Tlell river, formerly called Threemile creek. About 9 miles from Skidegate inlet these eastern highlands spread westward, and form a marked upland which extends to the Yakoun river, and separates the 2') Hnnna rnal lia>i?i from thr Vakoun i oal ha^in. '^outlnvi-rti, across till- (Ui|) valliy ol Hrent (Tick, ihl- upland is contiiuii'd in the l,0()()-foot hilK about (amp Kol)crtson. and rises lartiiL-r south into the 2,()()()-foot ikvation of ( onKl-nnuratr peak. Xnrthcasti-ni Louldiul. More than a thiril of the area of » '.raiiam inland is (■ompri>ctei(lual- of vr)lcanic tlow>, which formerly had a greater extension over the i>lan.l. Kr. -n M.i-Mt inlet, the contrast between the Hat. low, eastern shores ii, tlii- lowland, and the ruggeing a bench ami impeding dr.iinage. Very large ones f.irm on the tlat-roi)ped elevations of the Centnil I'lateau pro\ime. and on the lowl.nuls. It is not necessary that the bench or tlatlcmd area be level, for the surfaces of these musk<'gs ,it lime^ >lopeas much a> l.S degrees from the horizontal. Th. nuskegs are open spaces, in many cases dotted with stunted trees in straggly patches as well as single trunks (Plate VIl. The surface of the muskeg i, .i tou^h, matted, peaty mass of decayed grasses, m.iss. and i)lant stems, interlaced with the roots of growing plant.s. Low, bu~h\ i)ines, mountain hemlocks, and stunted jack-pines are the usual trees on the muskegs. Scattered irregularly o\er the surf.we are stagnant pools of water, tilled usually to within about a foot of i M) the Ki'iHT-'l lr\tl, and rontaiiiinj; iiuiiutliatilv IicIdw iIu- water surf UH- a tl()( c uknt mass ot brown decaxvil vt'Kft.ilik- matter, thirkrniiik' with (K[)tli. Ihc (l(i)ili <y to tliru>t .1 \v>\v (l,itation. Some of ihise op* n spaifs are aliUost h.dl a mill' in diameter, and their wind-swepi appiMrmee on a stormy d.i\ is desolate and forbiddiiit ever, they form 1 \\i-K"me inttrhidi- forest. In tine we.ither, how- the imnotonv nf the A m.irktd north-sniith depression rims the 'eimlh of (Iraham isl.ind: ill the north it is submer:cid, and forms Masset inlet; farther south it is ..niipied !>>• ti • \akoun river, and in the south by the I- • !i.i v,dle\-. This trench is believed to date b.uk to pre-C r'\, ■,iiis times, as it is largely oceupied by basin of Cretaceous sedimi'iits. The depression is at present not a sin;4lo valley, but is occupied b\- the valleys of sever.d streams, and while it forms a single depression, its lopoi;ra[)hv is (|uite di\ersi- fied. The Molina ri\er occupies a wide valle\-. car\eli *tnam> which an- -((laratwl in pan I'V a ralhi r Idw divid,- inmi Nak.uin Uivir (iiaiilauf. Till- triliiita-ii- of the u|.|wr lluitna fruiii the ui>i. CT«is>iM« the trail liilwiiii rani|i> roiirmilo ami F<v\ift littli- streams. tuiuhh'nK fnaii ilu' cud of the hij^h rid^c niimiiiy rast from Moum Kiluliiu'. This ridKt- is lotiipuM.I cil lu.is-ivi- Cntaccou- ^aiid-luiics and tonKtoiiuratis, ami ihr iillii.pc.. of the Udrotk on tht- topography is will shown in the \\,i\ that the (IrainaKf radiait- from tlii^ area of rc-i-iaui nx-ks, the trunk streams— Krent creek and the Honna river- tlouiui; in valleys exiM\,ited in -ofler, -haly lied-.. {{rent creek is a lar.;e eastern hrani h of the \.ik(Jim river and collect-, the drainage of the hiKlil.md .inJumlCamp kol.iTis,,n. Ris MK in the hills nearly _' niile^ soiiili ,,| the camp, il tl\ rock walls. ii-iuill\- -If-p except around ICtheline h.iy. .nid .u the northern end of the lake. 'Ihe shores ot Ijheline liay are low and swampy, .iial the northern end of ^'akoun lake is dammed li\ l.iw. humniocky. wooded hilU .i[)- parently of nl.icial drift. >imnlalinK mor.iine topo^niphy. The Handeck rixfr oicupie- .i wide v.ill.y, the ilirect continu.ition of the V.ikonn River valley, and Hows in .1 lir.iided ch.mnel o\i r much of its course. For the upper ,1 miles of its course the Vakoun river is crooked and sluKni-h. liut below the ijrade steepens slightly. The presence of numerous islets in the lake is evidence th.it it occui)ies a rather -ii.illow basin. To exi)lain the oriv;in of Vakoun Like, and the facts ^nveii abo\e the hypotlie-.i> is advanced that tln> Yak, un valley below the present north end of the lake was tilled with Rlacial debris, carried down by sm.dl local s;laciers. the sites of some of which are now representefl by circjuedike depressions and hanuing ^2 vallt-Vh we!*t of the norih vnA <>l S',ikcnin lake. That thr whole lake haftin wa> t'xc.»vat(1im\\h to Ih- iniprolialiU' or im|xi— -ililf liv the strep, uinilaciali'l ( har- acirr lit tht- i>ltt* in the lake. Thi-. ilammiii« of thi- valliA', (in |)ri'-< ilacial tinitl orcupitd li\- the piotnt M.Kl'lick ari'l Yakoiiit riviT". a- one ((intiiiuoii'. larnc -trcain, with I'.lliiliiU', Delta, .tml oilur . .i> trilmi.irio, iaii»eh.i(K'tw,ir(l iieiul of the N'.ikoiin r vcr, and «.e[)arate(l the iip[Mr p.iri ot the «*tre.ini, to forni the Haeldeck river. The i;Ia( i.il tiiiiiin rediiied the nr.nie of the vallcv, rau^inu the iipiHT put 'ilie M.iddeik river) to slacken it-. rate of cutting! and to lir.iid il> clLiniiel. ,tnd tlu' iipp« i re k he^ of the Yakotin to .1— uiite their pre-eiit >lilKKi-li char.icti r. Thi' N'.ikoiiii ri\(r lor tin- ure.itir p.irt of it sleii.;ih ok iipies a wide \,dli\. It tlow> in 1 ii.irrow ircnrh that is in pl.i'is canyon-like, with r.ick \v.ill> ri-itiu 50 tiet Irom the w.iier. .md in.iinlain^ .1 inoder.ite, lontiiiiioii-' ur.idr, iminleirii|)t>(l hy pronouiiiiil r,ipid>. KiiiiL; creek and the lower |)ari> of Hidden creek and ( iho»t river ai-o oi ciipy r.ither wide \alleys with moder.ite. iiniforiH urade>. The v.dle\-i tril)iltar\- to the -oiithwestirn en. The ~iilinieri;ed \,ille\s ocrnpied hy l.'vii^ .Arm, .ind Si.itechiick \alle\ .ire also remirk.iMv -tic|)- sided, narrow, depression*, .mil .-enn ti b.i\ e JM-en .illniil very little l'>' '.^d.ici.il action. The nortliern p.iri ni the ceiitr.il . cpre-~ic.n ol (ir.ili.un isl.nul is ()<■< ni)icd hy M.i— -el inlet uliich is \nui.ill\' the e-iii.iry of the >'akoiin river. Thi-re is app.ireniU no ^eolo^ic hrcik alonu thi- inlet, which prohihlv reprcs, nts the suhnuTgeil lower portion of tile ^'.lk<)UH l\i\et ■, .liley. Coast-linrs. The \arying effects of suh.iiri.ii md marine erosion .ictini; on rocks of different char.icters, ire well ilUistr.ited on ( .r.iham island, where several varieties o! rock lorm the sea Kjast. \'irtii.ill\ the wlmlc ..| ilic im«i CMi-i. .m.| ilic i; iiih ((..i-l from Kii-r -pii |i' M,i-^' I iitlci. |iri-»itl -.liiirc, '\h\- i« iaii«ril \l,i!bl. I li<- rlaii^i imi-- bar cxii'iKlitiv: iinr ihw.inl frnm M(iic^li\ i~laiiil .hki-- tin (tiii.iint nf '^Liiii j^aii- iiilt i is catiscil li\' a iiurtlnvanl ^I'l uf tlir liilr^, .liilr.l liv -truii^ -uuth- ea>t K''i'<"* that fri(iiifiitl\- -.wnii up llicatc ^irait-.. Ilic |i»w ancl \ tlir iiici tin- lA ciirri lit- -Wfcpinii iiialliwari! aliiii- till' (■ i-l ini-l .mil i-.i-iward ailing the north co.i-t. The --liiin-. of "^kidci;.!!!- inlet ,md the i-l,nid- in ilii^ w.itrr- wa\' arc -tccp am! rock iMiiiiid wlicrc tlicv ,iic llank' ' h\ the massive ai;nli)incnitc> of the ^'ako^m formation: win ii tin le--. resistant -ediinents of the 'Juicn ( harlot tc series oei nr the -h^re^ are more i;eiitly sloping. Where ni,issi\c yr.iniiii- rm ks are found on tin co.i-t the shores are extrenielv' ^teip with the re-iilt that in inanv' places, e>p its name. Thi* excellent example of a wa\i- ut stock rears its tree crowni-d head to a tlistaiice of 95 feet above high water mark. It is well illustrated in I'lates IX and X. ci.iM.vn:. The climate of (".r.diam island, though varying locdly, may be described as generally mild. Extremes of heat and cold are 34 seldom experienced and residents state that in the winter, which is hy .ill accounts the most agreeable season of the year, over- coats are seldom necessary . The west coast, like that of ^^ancouver island, has an excessive rainfall, and is usually enveloped in mist. The central and eastern parts of the island have consi(leraI)le rain and much cloudy weather in the early summer, interspersed with bright sunshiny days. .(Xugust is usually a month of sunshine, and the autumn is wet. In spite of the high latitude, snow does not lie on the ground at sea-level for any length of time in the winter. FLORA. Hemlock (Plate XV) is the principal tree and makes up more than half of the forest. Red and yellow ceflar and spruce are also plentiful and alder, yew, jack-pine, and mountain hem- lock are found. Some of the spruce trees are very large, not infre(|ucntly H feet in diameter at ,5 feet from the ground, and tower MM) feet in the air, carrying their size well up the stem. The yellow cedar is also a wockI worth sjxicial mention. It is very close-grained and works well with edged tools, owing to its honiogi'neity, and it takes a good |)olish. It is well adapted for interior finishing, furniture, and cabinet work. I'ndergrowth, exc('()t in the valley bottoms, and on coastal lowlanfls, is not excessively abundant. The uplands are gener- ally open: the principal shrub is a scraggly huckleberry, that delays, but does not seriously impede travel, and even it is some- times lacking. In the low areas, the bushes which include the huckleberry, salmon-berry, and ilcvil's club grow very thickly, and make travelling slow and arduous. Salal is found only near the coast of the island and in the Northeast lowlands, where dense thickets occur. OccasionalK-, thicki'ts of young spruce are encountered that are almost impenetrable, but the\' arc not commiin and on thi- whole the island is not so difticult of access as it has been reported to be, though it is not e.isily travelled. The surface of the ground, thickly covered as it is by layers of dear\(' .is traps f curious, also, to >cc a prostnitc tree trunk forming the site for a row of \onn);er trees, the trees of these parasitic hed^ies often all.iinini; considiTahle size. Rank growths of bracken, theweed, .ind other weed\- annuals are common in the more simny plaies, ,md form in some cases thickets very ditTicult to penetrate. Good stands of large hemlock are found in the central part of the island and smaller areas of large clear spruce and of red cedar. Yellow cedar urows on the higher portions of the island, where smaller stands were seen. The timi)er is virtually unin- jured by forest tires, of which only two have been recoriled, and these not of great extent. AGRKLLTLRK. The shores in the vicinity of Skidegate inlet are usually too steep to permit of extensive ruhiv.ition, but small are.is le\el enough for tilling are not infrequent, and excellent vegetables are raised without difticulty. In the interior no cultivation has been attempted, on account of the dense forest and the thick surface accumulation of dead ;ind decaying \egetation. The Northeastern lowland seems to promise mori' favourably, since it has a warmer climate ,ind is ~aid lo enjoy a gri-.iter percentage of sunny weather. I-'xtensive flat or gently sloping areas in the lowland are underlain li\- str.ititied sands and clays, covered by a greater or less thickness of \egetable matter. ( )nce these areas are cleared and drained, they siiould be well adapted to cultivation. Graham island, in common with sonu' other western com- mimities, has suffered at the hands of uii.-cnipulous re.il estate boomers, and \-arioiis misrepresentations, both fa\diir.iblc 'irl unla\ durable, have been given piiblicilv. Settlers li.ive been induced to come to the island without being .ip|)rised of true conditions, anil their ine\itable dis.ippointment and loss has reacted against the district. If lot al conditions in ng.ird to agriculture art intelligently studied, nun with abilit\- and some capital to start operations should make a siu cess of farming on the island. 36 COMMERCIAL POSSIBILITIKS. Apart from the mineral rLsourcos, (lesirihed at length else- where in this report, the natural proilucts of ("iraham island are timber and fish. The timber should prove of value in the future, and the fisheries, when [jroperly conducted, will also be of value. The whaling; industry is beinj; carried on with success b>- a comjiany with stations at Xatlen harbour, on Graham islann'..!sic (?). Batholithic intrusives: Kano quartz diorite. Langara quartz diorite. Diabase. Quartz diorite, diabase, etc. /r.. ntact. Middle Jurassic Lower Jurassic and Triassic ( ?) Vancouver group: V'akoun formation. Maude formation. . Basaltic agglomerates. Argillites, sandstones, and tulTs. DESCRIPTION OF FORMATIONS. In describing the formations in this report, a detailed citation of the localities where they occur is not given in the text, as these can be more readily got from the maps. The places mentioned are those that are important as type localities or for other reasons. A comprehensive summary of the main rock types found in each formation is given here, and detailed descriptions will be found in the chapter on "Petrography." 40 VANCOUVER GROUP. Rocks of the Vancouver group make up virtually all of the surface formations on the islands south of Skidegate inlet, and on Graham island arc with few exceptions found unconformably underlying the Cretaceous rocks. The Vancouver group is divided into the Yakoun formation, of middle Jurassic age, and the Maude formation, referred to the lower Jurassic, and pos- sibly in part Triassic. MAUDE rORM.\TION. Distribution. The rocks of the Maude formation are typic- ally exposed on the shores of South bay, and on the south side of Maude island in Skidegate inlet. They are also the surface bedrock formation underlying a large area northwest of Camp Robertson in the Yakoun valley, and on the hills between the \\ilson trail and the Yakoun river, and arc extensively rep- resented w-cst of the latter stream. Representatives of the Maude formation arc found on Frederick island, and the sedi- ments of the northwest corner of Graham island also are thought to be of that age. Lithology. The Maude formation is made up of detrital sediments, with a few bands of pyroclastic material near the top. The lower portion is composed of black and brown, fine-grained, banded slaty and flaggy argillites (Plate XI). These rocks are highly fossiliferous, and are remarkable for the abundant flattened ammonites they contain. Many of the bands are very car- bonaceous, and where they have been crushed or slicken.sided, often simulate coal seams. The "No. 2 coal mine" of Richardson (see page 7) was without doubt situated on a band of this nature in the argillites. A marked characteristic of the flaggy argillites is their strong bituminous odour and films of tar are found on many of the bedding and joint surfaces. The upper part of the Maude formation consists of fine, even-grained, often well laminated, greenish-grey, feldspathic sandstones. The sandstones are very massive, and tougher and more homogeneous than those found in the Cretaceous, though in general appearance they resemble them. Near the top of the 41 formation, where it begins to grade into the overlying V'akoun, the sandstones contain many tufaceous and agglomeratir beds. On the southeast end of South island are massive limestones, light grey in colour, partly crystalline, and strongly bituminous. They are provisionally classed with the Maude formation. At Pillar bay, on the north coast of Grahr.n island, and westward from there along the coast for over 2 miles are expo- sures of coarse conglomerate (Plates IX and X) greatly resembling the Honna conglomerate of the Queen Charlotte series. The beds underlie apparently conformably, sediments that are almost certainly referable to the Maude formation, and the conglo- merates may represent the basal beds of the latter. Metamorphism. In the field, most of the argillites, especially the banded flaggy varieties, have the appearance of considerably metamorphosed rocks, and this appearance is accentuated by the sharp local folds in which they are frequently disposed. Under the microscope, however, the metamorphism is seen not to have been extreme, and what has taken place seems to be almost wholly the result of pressure unaccompanied by extensive heating or hydrothermal action. Muscovite, chlorite, and calcite, with, perhaps, in one instance, recrystallizcd feldspar, are the only minerals whose origin is directly traceable to met- amorphic processes, and muscovite is not largely developed. The presence of flattened, though otherwise well preserved fossils indicates simple pressure unaccompanied by shearing, except locally, and this static pressure best explains the compact- ness of the rocks, their fissility along bedding planes, and the slight lamination apart from bedding, but parallel to it, observed in some thin sections. The thicker and coarser beds at the top of the formation, though thoroughly indurated and hardened, lack the metamor- phosed appearance of the finer, flaggy argillites. Structure. — Internal. The Maude formation has been folded considerably on the whole, an ' in many cases severely in detail. The general strike of the formation is about north 30 degrees west. The dips are usually high, few under 30 de- grees, and generally between 45 degrees and vertical. Localized, recurrent zones are very severely folded and contorted, twisted, 42 and mahhed. Those zones, extending for a few score yards, alternate with broader areas in which the folding has not heen so severe, and the rocks lie regularly disposed for considerable distances. In the tightly folded zones the mashing and twisting of the beds has been extreme, though faulting, apart from minf)r slips, is rare. The closeness of the folds, and the sharpness of the turns in them, with the absence of extensive faulting indicates that these rocks were folded under such pressures that thcv were sensibly plastic. The recurrent zones of severe contortions, separated by less disturbed areas, were caused by the moun- Sca/e of feet (jeolo^ico/ Survey. Canada Figure 2. Sketch of low cliff of ar^illites in the Maude formation on King creek, illustrating typical manner of folding in these rocks. Note parallel folding and carinatc anticline. tain-building stresses having been pericxlically relieved by failure of the beds in these zones. The types of folds into which the rocks are bent, and typical minor faulting are well shown in Figures 2, 3, and 4 and Plate XI B. The rocks are extremely jointed, most joints being normal to the bedding, and many containing films of black, tarry matter, which abo occurs along bedding surfaces, and in irregular veins of coarsely crystalline yellowish calcite cutting the argillites. The thickness of the formation is unknown, as the base has not been seen. Dawson' describes very similar rocks as occur- > Dawwn, G. M.. Geol. Surr., Can.. Rept. of Prog., 1878-79, p. 55B. ■Mi rinn in Soctiori cove, with a tliickno'i of alxuit 1.7(t() feet, so the Maude formation is at Ici^t that thick in thai loiMhlN. (Kit twice the thickness oliservi'il l)y Dawson is cxpo-.Kl dtj Kinj; criftv, a section alon^; which is shown in l"ii;ure 5. At lea>t .^.StK) Ut'C third S'ZR Figure 3. Sketch of a faulted band of laminated argillites in the Maude formation on King creek. feet of the Maude formation is visible there, with no sign of the basement on which the formation rests, nor any evidence of basal beds. If, as is probable, the basal betls are represented bv the thick conglomerates of Pillar bay, on the north coast of Ciraham island, the total thickness of the Maude formation may reach 9.()(X) or I(),00<) feet. Structure. — External — Relaliiiti to Younger Formations. The Maude formation grades conformably into the Vakoun forma- tion whiih is the upper number of the Vancouver group on Graham island. This relation is well shown on the south shore of Maude island, and on th<' opposite shore of Moresby island. Near the centre of the south .-^ide < ' Maude island the rocks are typical, well banded, tine, dense argillites, in part slaty, and are a/vI/^%^^ One -tenth s/ze Geo/og/C3/ Surrey, Canada. Figure 4. Sketch of faulted band of laminated argillites in the Maude forni.ition on Kinj; creek. A photograph of this same b i is given as Plate XIB. fossiliferous. Eastward along the shore, the rocks i :■■ well e.xposed. They occur in moderate folds, and are coarser and thicker bedded. As the horizon of the Vakoun formation is approached, tufaceous material becomes more prominent; but the rocks are still hard, fine, and evenly bedded, and are clearly transitional in character. Farther cast massive greenish breccias of the Vakoun volcanics form bold, precipitous cliiTs. -A t .,v->^ o V^ i V] ?V:I \\ y V 7 Si J 1 s. J. '3 'sZ 46 'I'll- M.i'u''' lormnidn is iincnnfDrmaJily ovfrl.iin Jiy the nuot'n ( liiilcitif sirifs oti V.ikoiiii riviT, ii\ir, Kini; rrfck, Tlcll rivur, north iif :\t DthiT linalitiis. I'llibli's of thu ir- . fhi- Hi)nna conKlonKrate, aiiil in a iia-al ida formation at tht: southwest end of Haida tncT!! KT i i Hidden creek, i '>o fanip kt hert-^on .u niliiies -ue contaim-d connlciiicrate o ' Yaivoiin I ih The Mi u.i' :.ix!i,iti are intrnchd iiv coarse graini'd green dial)ase in la- . . .^cs, ^lerhaps of batholithic affinities, alon^! the south shoi l.' -m itl bay. Origin. 1 .c f. . f the Maude formation clearly ^hows it to be of tn; t! by the renula.i* their fine gra r the formation dctrital in origin out the njcks, ,' that parts of t'.e tormation The • -it tilt Of. n ,11 The, . . I the . iia'-inu ()ri,;in is also borne out ' A\ marked bandiiiK, and ,, provi7,ionally (Drrelated with me; but largely, if not wholly mount of fresh plaRioclase throunh- "eous material in them indicate le.ist, and certainly the upi>er beds, are of psroclastic origin. Forming, as they do, an inter- calation in a ^',iick volcanic seri< . this orinin is not surprising- The fineness of prain, and the abundance of organic remains point to their accumulation in a sedimentation zone of moderate depth. Their [irtsent induration has been explained as the result of pressure without shearing, cause, notabh the head- waters of the Tlell river. Ar ur.d Yakoun lake the formation S 48 is found in steep, bare cliffs, and is typically exposed in Delta creek. It is also foun1. Surv.. Can., Rept. of Prog., 1872-73, p. 62. 56 Marine fossils occur throughout the Haida formation, sometimes in great abundance. Stratigraphy and Structure. The Haida formation varies in its internal stratigraphy from place to place, and cannot well be described as a whole. On Skidegate inlet several sections of the rocks are found some of which are complete. The Bearskin Bay section extends from Haida point, where the basal beds rest unconformably on the Yakoun volcanics, westward beyond the mouth of the Henna river, where the Haida 's conformably overlain by the Honna conglomerate. The rocks dip westward at moderate angles, undulating somewhat in the upper portion. The lower half of the formation consists of massive and flaggy, greenish and greyish sandstones and arkoses, with shaly interbeds. From Queen Charlotte westward the upper half of the Haida is much finer and the beds are thinner and more shaly. Con- cretions and concretionary layers abound, and weather in relief, simulating sills. False bedding is frequently seen, especially in the lower beds. On Maude island another complete section is exposed. The basal beds fringe the eastern end of the island and form a band across the central part, with a westerly dip, surrounding an old projection of the Vancouver group. False bedding is remarkably well shown on the southeast end of Maude island. Several hundred feet of the lower part of the formation are composed of a very massive, fine-grained, greyish-green sandstone, with shaly interbeds, well exposed on the northern side of Maude island, and in part on the southern side of Lina island. This massive band has not been recognized in the Bearskin Bay section, less than 2 miles distant. The Haida formation exposed in the vicinity of Camp Robertson is different from cither of the above sections, and is clearly divisible into two members, the lower about 3,000 feet and the upper averaging 2,300 feet in thickness. The Robertson coal seam occurs about 200 feet below the base of the upper division. The lower member is made up of alternating beds of 57 fine grey shales, medium-grained sandstones, and arkosic con- glomerates, a great deal of the detrital material having been derived from the Yakoun volcanics. These rocks are best exposed in Robertson creek, but a fair idea of their character may be obtained from the following columnar section measured in a small creek northeast of Camp Robertson : Feet Fine grey sandstone Coarse grey sandstone 55 Massive, fine grey sandstone 20 Mostly concealed, probably coarse light grey sandstone. . 60 Fine, laminated, crushed shale Wry fine, drab, jointed sandstone 8 Laminated, red shale Coarse pebbly sandstone. . •. 20 Medium-grained sandstone Laminated, grey sandstone 3 Fine, drab sandstone 10 Coarse pebbly sanH.stone Li(;ht grey siindstc.-. ■ Laminated, grey sandstone Dark grey sandstone Light grey sandstone Dark grey sandstone Light grey sandstone Dark grey sandstone (5 Fine-grained, drab sandstone, partly concealed 45 Finer-grained, drab sandstone 12 Medium-grained, ,;rey sandstone SO Total 302 Inches 1 1 1 4 t 2 4 4 8 3 The upper member is much more homogeneous, and con- siiits of very massive fine, even-grained, bluish and greenish, quartzose, grey sandstone, often beautifully laminated, and occasionally showing signs of irregular current bedding. In- terbeds of thin bedfled, flaggy sandstone occur. Throughout the area in >vhich the thick-bedded sandstone is found, the dips are flat or gentle. The recognition of this massive band of Eandsr.)!ie is important for prospectors, for the known coal horizon is fruiid about 200 feet below its base. i 58 In the part of the Yakoun basin exposed on the TIell river the beds are coarse arkoscs derived from the underlying vol- canics, with shales, some bands of massive sandstone, and a great deal of fine quartzose conglomerate. Farther north in the same basin the rocks are variable in their nature, at the base consisting of volcanic arkoses, overlain by shales and about 250 feet of fine massive sandstone. The sections are not constant even over small areas. The section found in the bore-hole of the Graham Island Coal and Timlicr Syndicate, in the eastern part of section 36, is given in the ap- pendix, together with other partial sections of the formation obtained from cores of bore-holes. East of Alliford point in Skidegate inlet a narrow sandstone dyke was found cutting fine dense black shaly sandstones of the Haida formation. The dyke, which is 4 inches wide in places, is lenticular and splits into ramifying branches. It is vertical in attitude and has a very sharp contact with the shales.' In thickness, the Haida formation varies. At Skidegate inlet, it is from 2,000 to 3,500 or 4,000 feet, while near Camp Robertson it is nearly 5,500 feet. Here, the lower member is from 2,500 to 3,000 feet thick, and the upper massive sandstones are about 2,300 feet. The coal seam here occurs alxiut 200 feet below the base of the upper massive sandstones. The thickness exposed in the Yakoun basin is probably under 1 ,000 feet. Folding and Faulting. Folding in the Haida formation, while locally severe, is gentle on the whole. Near the base and in the vicinity of the coal seams and without doubt els-i- where, close folds are found representing the relief of stress in the less competent beds. Faulting is also a local phenomenon, and several small faults, usually reverse, have been noted in the coal openings at Camp Robertson and Camp Wilson (See Figures 12 and 22). Relation to the Vancouver Gro p. The Haida formation rests unconformably on the rocks ot ti.e Vancouver group and includes fragments of these rocks. This relationship was noted at Haida point, the Channel islands, and Maude island in 1 Cf. Clapp, C. H., GeoL Surv.. Can., Mem. 51, p. 75. ^atm 59 Skidegate inltr , on the Yakoiin river; at Yakoun lake: on the Tlell river and Wilson cTLvk. and eU-where. The surface on which the Haida sediments were laid down was a very irreuular one, and projections of the older rocks are found in the lower beds of the formation. Relation to the Ilonna Formation. At Lina narrows in Sk .legate inlet, the Haida formation is conformalilv overlain by the Honna conglomerate. The upfwr beds ol the Haida are f^ne, sandy shales, and at the very fop are coarse, calcareous and concretionary sandstones, grading in a short distance into coarser, pebbly sand-tones that may l>e conMdere Formations. \ h t.., of tho Ffh I" voIcan.cs cutting the Honna formation h... .en n 'ed''' Mount Ktheiine flows of the Mass,, vnl-.n" '^ overlie the conglomerate. ^"^ unccn.oni.aMy SKinECATE FORNfATION .he n!;:tr„,'^t: weSfr::"?^'" '"■' 7-"' "-^ there extends i„lun,l nor.h™^ 1 S'" '"'"■ ''"'' '""" ..»u. , „„ „„,h't„7™:h"i-, L;:re -; s:r' ,?,: ..«n."t;ru^.^,^f?rz::rjrrht b».We,„heri„«, ,ili, enu, a„».!« exposed). Honna Frmalion. Pelccypods: Inoceramus sp. cf. /. labiatus Schlotlieim. Haidti Formaiion. Plants: Fern pinnule. Echinoids: Spines with imprint of fragment of test. RhynofHonella ? sp. frachiopods: i . Pclecypods: Trtgonia diverskostala Whiteave.s ? Trigunia maudensis V\hiteaves ? Cytherea subtrigona Whiteaves. 66 THetis affinis Whiteaves. Inoceramus sulcatus Parkinson. Inof.«ramus mpresbyensis Whiteaves. Inoc^mu^ sp. cf /. quatsinoensis Whiteaves. Inucramus sp. cf. /. labiaius Schlotheim. Ananaa Itnensis Whiteaves. Pecten {Ectoiium) lenticularis Whiteaves? Tellina skidegatensis Whiteaves. Kucula (Aciiii) trumcata Gabb? Thracia ? sp. t\rmod(m sp. Pecten sp. CucuUoea sp. Nucula sp. Tn^onid sp. Cyprina sp. Teredo ? sp. Corbuia ? sp. Astarte ? sp. Pkuromya ? sp. Cylherea ? sp. Undetermined pelecypods. Gastropods: Amauropsis tenuistriata Whiteaves. Undetermined gastropod. Cephalopods: De^moceras iPu«,«a) planulatum .' Sowerby as identified by VVh^eaves. Desmoceras (Puzozw) pereaanum Whiteaves. Lytoceras {Tetragomtes) timotheanum (Mayer). Lytoceras sacya (Forbes). Perisphinctes skidegatensis Whiteaves ? Desmoceras sp. Btlemnius sp. ,„.>.■ Undetermined ammonites, one possibly Pnonatropis. TERTIARY FORMATION'S. ETHELINE FORMATION. The Etheline formation consists of dykes sills, and prob- ably laccoliths of volcanic rocks intrusive mto the -^^s of he Vancouver group and the Queen Charlotte senes. The effusive J 67 basalts of Mount Etheline were in 1913 thought to belong to this formation, and the name was given for this reason, in the writer's Summary Report for that year. Field work in 1914, aided by study of the rocks in thin section, made it evident that the basalt flows of Mount Etheline and elsewhere in southern Graham island are to be correlated with the Masset formation, of later Tertiar>- age. The formation name Etheline is thus res- tricted to intrusive volcanic rocks. No effusive tvpes have been recognized as belonging to this formation, although it is possible that they may occur. Distribution. Dykas and sills are of frequent occurrence over %irtually all of southern Graham island. They are partic- ularly abundant in the rocks of the Vancouver group, so that m some localities as on King. Canyon, and other creeks, the intrusive rocks occupy areas as large or larger than does the in- truded formation. There is thus a marked tendency for the older formations to contain the intrusive rocks in greater abund- ance than the younger ones; and this is the case even in the Queen Charlotte st-ries, where few dykes or sills penetrate the Honna conglomerate. In the vicinity of Parry passage, between Langara and Graham islands, are numerous intrusive rocks, which on account ()l lithological similarity are cc.rrelated with the Etheline intru- sives, Lucy island, and the larger part of Cape Knox consist of one of these intrusions of biotite andesite, in the shape of a huge (iyk-e, which is at least a mile wide, and 5 miles long. Litholo^y. In composition the dykes range from dacite to basai". and virtually all the volcanic rocks of the series are re- presen.ed in dyke f-.rm, while all but the dacites are represented as sills. Thedeterinina'ionof thesev. .1 types is next to impossible *fl the field. The dacite. .nd quart/.-htaring andesites are light <>A(mred rocks, generally pale grey, and are characterized usually b>- phenocrysts ■,{ quartz and plagioclase. The andesites are ■^imii.^. but la^k ti-^. quartz. The augite andesites and basalts are da#t«.r grey rocks. All the rocks show porphyritir facies ^d the ^roundmass is in every case verv fine-grained. Most o* -hem ar«: rharacterized by finely divided, disseminated pyrite. 68 More detailed descriptions of these rocks will be found in Chapter V. Structure.— Internal. The widths of the dykes vary from a fraction of an inch to SO feet or more. Sills up to 200 feet thick have been met with, but they are exceptional, and may be a c c:3 o o o " o O o o <0 c3, o . O • Geo/og/cj/ 5ur\/e/, Canada Figure 6. Vertical section of andeslte sill on north side of Triangle island. Skidegate inlet, cutting shaly sandstones. Illustrates ch.l ed contacts, and upward translation of vesicles. Sill is 3 lect o inches thick. laccoliths. The average width of the dykes, excluding two of 30 and 50 feet respectively, is about 5 feet. There is little variation in the internal structure of the injected bodies. Many show chilled contacts in varying degrees, but it is not uncom- mon to find the grain uniform throughout. Some of the bodies 60 i * 1 are vesicular and amygdalf)iflal, and a sill on the north shore of Triangle islund contains vesicles so distributi'ij as to indicate their translation toward the top of the sill under the influence of gravity, as shown in Figure 6. On the south side of I.ina island there is a comiiosite sill of andesite, with hiter augite andesitc porphyrite occupying the same cavity. Aplitic stringers up to an inch wide, irregularly disposed, and grading into the rest of the rock, were found in a hornblende an(U>ite dyke, a rare type containing small phenocrysts of hornblenile. The aplitic veinlets are much less altered than the andesite contain- ing them. The same dyke contains an irregular altired shale xcnniith about ,^ feet in diameter. The severe heating which the xenolith has undergone has not altered it appreciably and vir- tually the only change it has sufferwl is a partial replacement by pyrite. Other smaller xcnoliths of shale are commonly found near the margins of the dykes, where they have been stoped from the walls. Structure. — External. The most striking external action of the injected bodies is their baking action on the rocks they intrude. A hardened, resistant ;;one is found liordering the dykes and sills in almost every case, but there seems to be no definite relation between the widtli of the zone and the thick- ness of the intrusive, indicating a varying amount of superheat in different dykus. The zone is up to 2 feet thick, and weathers in relief, generally adherinc: strongly to the dyke walls. This is illustrated in Plate XIFB. The actual contacts of the dykes and sills with the shales are linear in the main, but remarkably irregular in detail. A zone one-fourth to one-half inch in thick- ness occurs paralleling the dyke, in which there is an intimate interpenetration of intrusive and enclosing rock. This gives the surfaces of the dyke walls an irregularly pimpled appearance when exposed. The sills are not in every case strictly concordant bodies, some of them cut across the strata for short distances, and re- turn to the bedding planes. In places i\ gap appears between different portions of the same sill, as illusliated in Figure 7. This is analogous to the dykes described and figured by Marker'. 'Marker, A "lertiar^' Igncou; Rotlts of S«ye. ' 1904. [,. 303. 70 Some of the dykes show a similar structure, and particular caM s are illustrated in Figures 8 and «>. In the case of Figure y llicre seems to have been an excess of magma at the point illii-trati(l and the overflow forced its way irregularly into the saridstcne. Geo/ofiica/ Survey Canada. Figure 7. Plan of 4-foot andesite sill on east end of I.ina island. Skidegate inlet, illustrating intrusion en echelon, baking of sediments, and later, 6ner grained andesite dyke. That some at least of the dykes and sills were injected before deformation ceased is shown by the tightly folded sills occurring in the tunnel of the British Pacirtc Coal Company, and by the folded and faulted dyke in the tunnel at Camp Robertson, Figure 12. Method of Intrusion. It will later be shown (page 113) that the dykes occupy almost exclusively fissures belonging to one of four systems of joints. The joints of this system, therefore. 71 must extend to considerable depths and they are considered on this account to be the master joints of the region. Into these deep fissures the magma was forced under enormous pressure, filling them with great rapidity. The fact of the occurrence of I Geo/o^/ca/ Survey, Canada Figure 8. Irregular amiesite dyke cutting shaly sandstones on beach west of Haida point, illustrating also the baking of the sediments. such thin bodies of igneous rock so far from tlieir source proves two things: a large amount of superheat in the magma, and a very rapid intrusion. Age. The Etheline sills and dykes cut the Upper Cretaceous beds of the Queen Charlotte series, and are, therefore, younger i 7-' than these beds. Some of them are found in ft.l.kd strata, and it swrms probable, therefore, that they were intruitid before the folding took place. Othersi arc faulted. This evidence aUliough ■o/-:vy^ X , ■ _" \ .V, ^ ^ ■*■ N ■ * .,"N . N X'^ X^ *'25' Scci/e of feet , , -? ^ O/Ae /s vertical Geological Survey, Cjnado . Figure 9. Irregular andesite dyke cutting shaly sandstones on beach west of Haida point, illustrating also the baking of the sediments. not altogether satisfactory, indicates that the intrusives are not very much younger than the Upper Cretaceous. They are nowhere found cutting the Masset or Skonun formations and, 71 therefore, arc older than these kds which are at least a« old as mid-Miocene. It seems In-it to oin>i(iir the Fuhiline formation as of Eocene a^c and prohably early Ko1PPLIEL3 IIVHG E In '653 East Main Street Rochester. Ne«r York 14609 USA {?16) *B2 - 0300 - Phone (716) 283- 5989 - Fo« ^ 74 the sandstones are frequently cross-bedded. At Skonun point the beds are disposed in an east-west anticline, apparently faulted on the crest, and with dips up to 60 degrees. Most of the exposures seen were flat lying, or nearly so. The formation as a whole appears to have a gentle northeast dip, and is uncon- formable on the rocks of the Vancouver group in township 7. The total thickness of the Skonun formation is unknown. A bore-hole put down at Skonun point for the American-Canadian Coal Company is reported to have penetrated to a depth of 1,003 feet, at an angle of 45 degrees. Owing to the dip of the measures, this nearly represents the true stratigraphic thickness passed through, so the formation may be considered to be over 1,000 feet thick. The writer has not seen the contact between the overlying Masset and the Skonun formations, but from the general areal distribution of the Tertiary rocks, it is thought that the Masset formation overlies the Skonun with overlap or unconformable relations. The alternating sediments and basalt flows on the Mamin river may indicate that the upper part of the Skonun formation contains intercalated basalt, but the relations are not clear. Origin. The variable character of the sediments and their cross-bedded structure points to a shallow water place of origin. The fossil leaves indicate a location near shore, while the marine fossils show that the water was at least brackish. The beds of lignite, though derived in part probably from transported material, hints at a freshwater origin for part of the formation at leaet. On the whole, it seems best to consider the Skonun sediments as beds formed in shallow estuarine basins, parts of which were at times cut off from the sea and converted into freshwater lakes or swamps, and at times reverted to estuarine or marine conditions. Age. The fossils collected from Skonun point by Dawson were examined by Whiteaves, and his determinations and re- marks are given here in full.' » G«oL Surr., Can., Kept, of Prog. 1878-79, p. 87B. •V!f /.I "dasteropoda. Mangelia ? sp. •indt. One worn sf)ccimen. Nassa, sp. Ui.:.ke any of the livini; species on the N'.W. coast. Lunatia ? sp. Test exfoliated. Trochita, or Calcrus. Test e.xfoliatcd. Crypta aduncci, Sby. One s|*cinicn; undistinguishable from the living species. .Mr. Cahl) (,1'al. Cal. vol. 2, p. 82,) l- .%s that this shell occurs in the Plioceae and IVst Pliocene of California. Lamellibranchiata. Solen, sp. One fragment of a large species. 5i.'ig«a— Possibly the young of S. patula, Dixon. Two examples. Standella—Xitr/ like S. planulata, Con., and 5. fakala GId., but smaller than either. Several specimens. Macoma nasula, Conrad. Two or three specimens. According to Gabb. (Pal. Cal. vol. 2, p. 9,?) this recent species occurs also in the Upper Miocene, Pliocene, and Post Pliocene of California. Mercenaria—Mr. VV. H. Dall thinks this shell is closely related to his M. Kennicotti, from Alaska. Chione, sp. undt. Two specimens. Tapes slaminea, Conrad. The most abundant shell in the collection. It is abundant, in a living state, on the N.W. coast, and Mr. Gabb says that in California it is found in the Post Pliocene, Pliocene, and Miocene. Saxodomus, species undistinguishable. The outer layer of all the speci- mens, which are not numerous, is entirely exfoliated. Cardium, one exfoliated valve. Appears to resemble C. Islandicum. Cardium. Several valves of a species, which may be referable to C. blandum, Gld. Area microdonta, Conrad. An extinct species, found so far only in the Miocene and Pliocene of California. Two specimens. Axinaea. Possibly a form ol A. patula, Conrad, but barely distinguishable from the smooth form (var. subobsoleta Carpenter) of the living A. septentrionalis, Middendorf, of the N.W. coast. Four single valves." From this list it would appear that the Skonun formation is either Miocene or Pliocene in age. Ariold and Hannibal* correlate the Skonun sediments with the Empire formation, of middle Miocene age. ' Proc Am. Phil. Soc. vol. LII, 19U, p. 592 76 The follcnving Miocene fussils from Skonun point were collected by the author and were determined by Dr. Ralph Arnold : Paphia sp. C". Caesia sp. K. Cryptonccica clausa B. and S. Hemimactra cf. albaria Conr. M ASSET FORM.^TION. Distribution. The Masset formation is a name applied to the late Tertiary volcanic rocks of Graham island, which form virtually all of the surface rocks west of Masset mlet and north of Rcnnell sound, and which occur in other parts of the island as well. These rocks are well exposed along the north and west coasts, around Masset lake in the interior, and in the Slatechuck range in the southern part of the island. Lithologv. The Masset rocks are almost wholly basaltic. Bedded flow; and coarse agglomerate beds (Plate XIIA) make up nearly all of the formation. The basalt^ are characteristic- ally dark grey or black, heavy rocks, and range in texture rem glassy to highly porphyritic types. Amygdaloids are abundant the amygdules being filled with chalcedony, quartz, calc.te, and occasionally black sticky tar. Basaltic glass or tachylyte has been found on Ship Kieta island, in Masset inlet, and in some of the streams entering Athlow bay on the west coast. It is reported al^o from the west side of Juskatla inlet. Agglomerates in bewildering varieties of shape, size, and proportion of frag- ment to matrix, occur interbedded with the flows. Fine- grained, bright greenish and bluish, curiously banded tuffs are found near Tian head on the west coast and elsewhere in that vicinity. These are the rocks in which it is hoped by some to find petroleum by drilling. Besides the pyroclastic rocks, sediments of detrital origin make up a part of the Masset volcanics. They were seen on the southeast slope of Slatechuck mountain, but were not care- fully studied. Some of the beds are conglomerates, composed of pebbles of volcanics up to 6 inches in diameter, in a dense 77 tufaceous matrix. A large exposure of brillatu red, soft, ar- gillaceous sediments was seen se\eral hundred feet below' this conglomerate. These beds are at least 100 f.et thick, and may be much thicker. The lower 40 feet inclufles some sills or flows. Some of the hills east of Otard bay and Fort Louis on the west coast are formed of bright red, bedded rocks, perhaps sedimentary and similar to those just described. These ferruginous rocks, occurring in a great volcanic series, recall the deposition of hematite mud at the present liay in the Hawaiian islands,' another region of basaltic rocks, and may be worth while prospecting for beds of sedimentary iron jre Structure. —Internal. The Masset formation is formed of bedded flows and agglomerates usually not exceeding 100 feet in thickness, both of which may be considered as thin and relatively extensive lenses. This bedded nature of the forma- tion is well seen in the Slatechuck range and at Lawn hill and in fact in every exposure of the volcanics except those of very small size. Many of the flows show well marked columnar jointing. This jointing has been noted on Mount Etheline and in a high degree of perfection on the west coast (Plate XII IB). Flow structure, so beautifully illustrated in thin section, is well brought out by weathering in several localities, notably at Lawn Hill beach. Chalcedony and calcite veins intersect the rocks at Lawn hill and Tian point, on the east and west coasts respectively, at both localities carrying tar. Structure.— External. The actual contact of the Masset volcanics with the underlying Cretaceous rocks was observed at two localities on the southeast slope of Slatechuck mountain. The contact is very sharp; the basalt is chilled for several inches above its lower surface, and exhibits a distinct columnar and rude platy jointing, the former perpendicular to this surface, and the latter paral' ' *o it. This lower surface is generally smooth, butjn deta aewhat mammillary, with projections reaching ' Lindgren. W.. "Mineral deposits." McGraw-Hill Book Co.. New York. N.Y.. p. 200. 1 78 hcisht. of one inch and corresponding hollows. The only al- teration in the shale, i^ a slight softening vvh.ch may be a.cnbed to percolating water. Angular blocks of shale are found .n the ower portion of the flow, and the surface of the shale, whe e overflowed by basalt, is as clean as if it had been subjected to erosive water action. . , Th. lower cntact of the formation has not been sufhc.ently observed to determine the character of the surface on which the basalts were extruded. . . It can be stated that the Masset formation has been acted on by deforming forces to a considerable extent, though as the work done in the areas underlain by this formation was largely Tf a reconnaissance nature, th. structure has not been worked °"^ Tn the Slatechuck range, the formation is about horizontal, with possibly a low westerly dip. At Lawn hill, the strike o the flows is east and west, dipping 10 to 15 degrees south. Jh- east-west trend of the folds is seen in many places although much of the formation on the west coast strikes from north 20 degrees west to north 20 degrees east, in low folds In some cases local folding has been severe, and is accompanied by minor faulting, but dips of over 20 degrees are uncommon. The on"y fault of any magnitude noted is one crossing Frederick Sand in an east-west direction, and b-^mg the Tertiary basalt flows, which in the northern part of the islaiid dip 20 to 30 degrees south and southwest, sharply against the lower Juras- sic Maude argiUites, also dipping south, but at higher angles. Thickness. In the Slatechuck range 1,600 feet of piled up basalt flows are visible in Slatechuck mountai: . On the west coast upwards of 2,500 feet are to be seen in steep hill-sides and from the folding observed the formation at present is estim- ated to be upwards of 5.000 feet thick. Method of Extrusion. From the description of the rov.k types in the formation, it is evident that they were formed duHng an extensive period of vulcanism, when great explosive vents vomited forth masses of so-called ash and fragments o^ hot lava to fo.-m the tuffs and agglomerates. Concurrently great flows of basalt were poured out, and the formation was 79 built up in this way. None of the actual vents from which this great basaltic accumulation came were seen, and it is improbable that any volcanic cones now remain. The tachylyte of Ship Kieta island is, however, evidence that one at least of the vents was in that vicinity. From the well stratified nature of some of the tuflfs it is inferred that their accumulation was subaqueous. Origin. From the character of the rocks, it is plain that the Masset formation is the result of extensive explosive volcanic action, accompanied by the extrusion of great flows of lava. What is now Graham island, may be conceived to have been aii archipelago in this volcanic epoch, or an upland with large lakes, as many of the tuffs and agglomerates are clearly water- lain. Into these water basins were also carried ferruginous detrital sediments, derived from the subaerial decomposition of the basalts, in a way analagous to the hcmatitic deposits of the Island of Molokai in the Hawaiian group.' Age. The Masset formation is younger than the Skonun sediments, which may in part be Pliocene in age, and is prob- ably conformable with them. It is older than the Glacial epoch, as many of the outcrops are glacially scoured and the basalts of the Slatechuck range have been greatly sculptured by ice action. Until the age of the Skonun sediments is definitely determined, the Masset formation may be considered Pliocene in age. COMPARISON OF THE VAKOUN AND MASSET FORMATIONS. A comparison of igneous rocks of different ages in the same district is always interesting from the scientific view-point, and, in the case of the Masset volcanics of Tertiary age and the Yakoun volcanics of Jurassic age, there is an important economic reason why these two formations should be compared and clearly distinguished. Between them lies the coal-bearing Queen Charlotte series, resting unconformably on the Yakoun volcanics, and unconformably overflowed by the Masset volcanics. To the prospector the ability to recognize which formation of volcanics— J^Llngdren. W., "Mlnetml depodu." McGraw-HUl Book Co.. New York, N.V.. 19U, 1 80 underlying or ovcrlying-he is dealu'.g with is of the utmost TL At least one case is known where several hundred feet of i-seless drilling was done in the Yakoun volcan.cs on the mis- taken assumption that they were the overlymg rocks. This mistake may in part have arisen because the outcrops occurred on a hill-side, above outcrops of the Ha.da format.on. M were not recognized as basal. The determmaUon of the fact that the coal measures were laid down on an uneven surface is thus seen to have a direct economic bearmg. Eros.on has in some degree bared the pre-Cretaceous topography, e.xposmg the S aSn^t which the sedime.Us of the Queen Charlotte senes were accumulated. It very often happens that the strat.graph.c- ally underlying Yakoun volcanics are. topograph.cahy. above the stratigraphically overlying coal measures, ow mg to normal processes of erosion having exposed the ancient topo- graphy It is essential to intelligent prospectmg that these peculiar structural relations be borne in mind, and U .largely on account of them that the prospector and geologist must fall back on petrological criteria for distinguishing which formation of volcanics he has encountered. Fortunately there are distinct megascopic differences, and only occasionally need there be any uncertainty as to the identity o?the formatio.; in the field. In these cases of doubt the power- ful aid of the microscope may be invoked, for the microscopic characteristics of the two series of rocks are even more distinctive than the megascopic. For convenience in reference the two formations are con- trasted in detail under the same headings. Yakoun Formation. Masset Formation. Age. Middle Jurassic P«<^^"^ ^'^ Stratigraphic Position. Unconformably underlying the coal- bearing Queen Charlotte series. Unconformably overlying the coal- bearing Queen Charlotte series. 81 Structural Relations. Hlglily jointed, sheared and broken, j Columnar joints, and otherwise veined with calcite and quartz, jointed hut not to such an extent and brilliant jas()cr. as the Yakoun formation. (See also page 80.) Basalt and andesite tuffs and agglom' crates. Rarely diabase. Middle Colour. Lithulogical Character. Basalts, agglomerates, and tuffs. Purplish, greenish, blackish, and dark grey; altered looking, and stained with epidote, chlorite, and limonite. A dull, mottled pur- plish and green tint is very com- mon. Dark grey or black; usually fresh looking and unstained. Agglom- erates often rusty. Texture. Typically fragmental rocks, tuffs, and very dense agglomerates. Fragments angul,- •, and of all sizes up to several feet. In some cases well bedded, in layers of varying thickness. Dense, por- phyritic, and amygdaloidal flows, and injected rocks are found. Fre- quently highly Torphyritic. Typically massive, dense, dcvitrified or sparingly porphyritic flow rtxzks, occasionally amygdaloidal. Frag- mental rocks are abundant, and a few bright red interstratified clay sediments are found. Columnar structures common. Agglomer- ates loose textured. Microscopic. Essential ir' 'ibradorite, AbijAnej-/ ; rarely- andesine; ubotdinate minerals: > titanice, rarely biot; ,ar>- chlorite, calcite, etc. Microscopic Wholly crystalline, finely even gran- ular or porphyritic; feldspar equidimensional; texture inter- •ertal or ophitic; flow structure rare. Essential minerals: labradorite, AbiuAnvo-AbwAnic; aiigite. Sub- ordinate minerals: magnetite. Secondary minerals: chlorite, cal- cite, epidote, etc. Texture. Wholly or partly crystalline; finely even granular, frequently por- phyritic; feldspar markedly lath- shaped; texture interscrtal, rarely ophitic; highly developed flow structure universal. Vitreous rocks found. 82 Alteration. Considcrahle-.tcldspar always partly or wholly kaolinized; augite altered to chlorite, etc. Very slight; small amounts of kao- linization; much of feldspar and augite quite fresh. SUPERFICIAL DEPOSITS. GLACIAL DRIFT. Glacial drift, both stratified drift and till, occurs in abund- ance on Graham island. The relative distribution and amounts o?each cannot be determined with any degree of accuracy owmg to the absence of exposures. Lithology. The stratified drift is composed of ammated fine blue clays, sand, and gravel. Much of the clay .s su.Uble for brickmaking. The uustratified till is made up of angular, subangular. and rounded boulders of varying sizes up to about 3 feet m diameter embedded in a matrix composed of sand and gravel m yarymg amounts. The boulders consist of several varieties of ign^u r^ks and of rocks of the Queen C harlot tc series, and many of them show glacial scratches and striations. Orim. The stratified glacial drift has been laid down in water and probably was formed in lakes or estuaries caused by Tlac al damming, as it seems improbable that a -ffi-^nt "phft Ls occurred to make it possible that the stratified drift seen ca" be of marine origin. The unstratified drift has all the char- acteristics of boulder till, and was formed by the usual accumu- lation of heterogeneous material. Some of the till is slightly sorted, and perhaps modified by wacer action. D.XWSON'S DESCRIPTION OF THE SUPERFICIAL DEPOSITS. The following description of the superficial deposits as exposed in the cliffs on the east coast of Graham island is taken from Dawson's report.' ~T^,»a. G. M.. G«>L Surr.. Can.. Ann. Rep... 1878-79. pp. 91B-93B. H,» 3 3 I 1 "The long lines of wasting cliff on tin tastward-fiKing shore present exnlicnt sections of the deposits of which this low land is composed, and these ap[H'nr with m ircely any exception to be those of the glacial or even yet more nuKlern jHriods. A few miles nf)rth of Lawn point, at the entrance to Skide- gate, the most southern cxptjsure is found in a low clilT or l)nnk, in which deposits evidently of (glacial aj; arc ( ut off alxne i.y a gently undulating surface of denudation, and overlain by ten or fifteen feet of sup«rficial material which shows no sign of blending with that fjclow. The upjKT deposit consists of sand and well rounded gravel, in regular and often nearly horizontal layers. It has become in pi. ices ijuite hard. Ixing apparently cemented with ferruginous matter. Its lower layers hold some small boulders, a few of which measure eighteen inches or two f»et in diameter. The lower deposit at the north end of the exjiosure— which may be in all about two hundred yards in length- is a typical boulder clay, with many half-rounded and subangular stones and occasional boulders of some size. The matrix is bluish-grey, hard and somewhat arenaceous. The whole is irregularly mingled, and shows no sign of bedding. The boulders were not observed to be striated, but smaller stones now loose on the beach were so. Among the fragments pieces of lignite from the Tertiary formation, which there is good reason to Ixlieve underlies all this region, arc quite abundant. When followed a fow yards southward this boulder clay begins to show liedding and to become interstratiried with hard clayey gravels composed of well-rounded pebbles. The bedding of these is undulating ^nd rather irregular, and there is, as may be supposed, some local unconformity by erosion between the different layers. A few paces further on these become interbedded with, and are even- tually replaced by, hard bluisl. / arenaceous clays, which hold only occasional pebbly layers, .t contain in abundance imper- fect and broken specimens of several species of molluscs, among which Leda fossa is the most common. A small Cardtum-Vike shell and fragments of a Balanus were also observed, but all broken, and tender from partial decomposition. In general appearance with their relation to the sea "evel, and the shells found in them, these beds resemble very closely K4 thos. prrvinu.ly .losrrilH-d as .KCurrinR in the vuinity -f Victoria, on the south-ot.rn ixtr.-mity -f Vancouver Islan.l. Ten mik. .lorth of (-ape Hall the last exposure, nf the clayey be,lH fornuuK the lower part of the section were observe, . he ; V s h..re very hanl. an.l in some places chst.nct y M the f.illDwiiii^ 'iHcii'.-t: — Hctiiilltyris psittaifn I. inn. Mi'diiildn'a nigra ("ir.iy. Saxiidva riinosn F. am. ink. Pnmttirelhi '^ah'atii (ioild. I f (lid Hits - f and fniKinentH nf hivaivi's, which an' m ircily ili'icriiiin.ililc. In M-vcrai dthcr pl.uis on this Mnind, >iinil,ir mikIv !>id» were st'fn generally w'lL-n near the water IcmI well ounpacti-d, but were not a^ain found U> hold shells. \t Kchiniis Point, on the south shore of the first nn.it expansion of the inlet, at low tide, a very hard sandy elav almost like stone is exposed. It is charged with pebbles and bouldc-s, some of which ap|)ear to be ice marked. Dejiosits of this character probably une rotks are plainlv the product of rapid weathering and hasty de,x.s.t.on. •ind uive little evidence of transportation. , . , , , Ouhonaceous sandstones have been seen-soft black rocks, containing finely divided carbonaceous sediment. SKIUKGATE FORMATION. Sandstone. The only specimen -']->-•' 7[':;';;';|;f^ from the Skidegate formation was one from ^he ba al b^d of dark reddish, grey, uneven-grained sandstones. In th n scUion, ^ul . c uartz. with some plagioclase and ^'-mposed volcan c rocks, wL seen to be embedded in a granu ar calc.te matr.x and calcite also replaces feldspar m some mstances. The shales found in the formation are fine, dark grey to black, massive, and banded carbonaceous rocks. ETHELINE FORXIATION. In composition the Etheline formation, which consists onlv of iniec^ed rocks, range, from dacite to augUe and .te. All' the tvpes are represented as dykes, and all but dac.te as f^ s Bas^t dykes occur on Graham island, but their general aoDearance and lack of alteration indicates that they belong to thTTa"" Masset formation which is almost wholly basaltic, so far as is known. Dacile. The dacites are dense rocks of ight grey colour showing green, blue, and more rarely pink tint, and virtual y nil ch"r.cteri.ed by yellowish or brownish weathering. They all characterize i y > phcnocrvsts occur in some of the cSs'. under 5 mm.; more rarely they are quartz. Small, irregu- -Tthc ,n, and avue .oc., . - ^^ .-"^ ^ ^^ f ::;;:isr r^rt^o::^.". Clnpp (Geol. Sun-.. Can.. ^""'^ f ^^^J. „;;„^„clature proper to their position a, t,ypaby«al with the effusive tyro». «> d.d not "^ '^^ ;™™„,i^i„,, nomenclature, rather than to cau*. 95 lar replacements of white calrite are frequently seen, and most of the (lacites are impregnated by finely divideine varies from Ab.,An„. to Al.«,An4o. 1 of,:: Lost unal.ere,l. and has a lath sha.K-d. ^1 v-«;"t '-dnt as in the dacites. The auKite is otten ronsulerably altered to chlorite, but nmch less so than in the .lacites. ( ompUt.ly crys- talline, finelv granular, intersertal textures preva.l. the aug.te in small equ .t grains being interstitial to the d.verKenl laths ..f Lnde^ne o, it may be-, in some cases inclu.ling them ,K.c.ht.- callv Pyrite and calcite impregnations are common 'Andesite Porphyrite. These rocks are very similar to the andesites. differing only in texture They have Ix^en observed as dykes only. Phenocrysts of chalky white, equant. euhedral plagioclase occur and make up in some cases 10 per cent of the rock Examined under the microscope, the phen.Kryst. are an- desine. greatly altered to calcite, kaolin, and ser.c.'e embedded in a groundmass resembling the nonporphyntic andesites m composition and texture, except that in some cases it is almost a devitHfied gla.ss. Umenite and leucoxene have been noted. The thick sills, some of them possibly laccoliths, that occur near the uppermost exposed beds of the Skidegate formation south of Lake Stanley, are mostly andesite porphyrite. They are light, bluish-grey rocks, with phenocrysts forming a much higher proportion of the rock than usual. One o them, studied in thin section, vas found to contain euhedral to subhedra phenocrysts of andesine. Ab.^n„ (about 20 per cent of the rock) in a grou.vi-nass comjjoscd of more acid an.lcsme. Ab.,An,o (about 60 per cent of the rock) the rest being augite almost wholly altered to chlorite. , j •, On the whole, the alteration of the andesites and andesite porphyritcs. while considerable, is much less marked than m the more silicic dacites. Much of the andesine is scarcely altered at all and many rocks contain fresh colourless augite. Aueite Andesite. The augite andesites are usually porphy- ritic rocks, with phenocrysts of chalky white plag.oclase or augite in a finely crystalline grey, greenish, or dark grey ground- mass. Phenocrysts in some cases make up as much as 15 per cent of the rock <)7 im Kx.itninwl microfjcopically, andesine nr andt sinc-lahra- dorite and auKiti' arc seen tf. hv thi- cssrnlial minerals; sonu-- timt's i)lKTi*ts of lahradorilc are found. Apatite occurs in bmall amounts, and chloritf, calcite, sericitc. kaolin, etc., arc the secondary minerals. The ann .\l)<....\n.„. The pl.n-i.K-l.isc is '-dy slightly altercfl, and the aunite, which is colourless, is oftet. .|,iite fresh. Alteration is much less noticeable than in the andesites and dacites. Biotile Amiesile Porphyrite. Rocks classifieeen nolcrt. ""•■1 h general family resemblance of the rocks .s also shown in their alteration. The characteristic change .s a chlor t.c replacement of au«ite. and a replacement of the mme aU, and rocks as a whole with calcite. Impregnations with finely granu lir nvrite are also characteristic. ''IlLuon. A striking feature of the Etheline forma Uon is the progressive alter.uion exhibited, this being greatest m Ihe mo't sHicic rocks, the .lacites. and uniform y becoming e. as the sub-silicic end of the series is approached T^^h^^e ar of course, exceptions; but the general rule seems to hold for met nf the 'ioecimens studied. The verv g. at alteration of augite and other ferro-magnesum minerals to chlorite, in these Tertiary intrusives - - ^^^ct" dication that processes more intense than usual have aftectul 99 thc-m. This is thv more apparrnt when wr rocall the small dtxrw of alttraJii.n undtTKoiu' by the very much older Vak.iun ba.siilts. The cviilcnro iK-aring upfin the question, what these pro- cesM-s prohal.ly were, may he summed uj) here. Ihc notic ealile amount of suinrheat in many of the intrusives at the lime ..f their injection i-* proved by the strouK baking action they have had on the enclosing sediment . as well as by the very fact of the occurrence of thinly tabular bodies in a highly li<|uid condition (Figures / «, ami 9) so far from their sources. The finely divided pyrite. found as impregnations— that is replacemints— in the dykes and sills aneen actvd upon by large ;imoimts of heatid magm;.tic water which n'ay well have been wholly or in part in gaseous form. MASS! T FORMATION. The Masset formation is wholly basaltic except for a single occurrence of a tr.:rhyte of bostonitic habit, an unusual rock type. Wherever examined, with this single exception, basalt, ofjill varieties of texture, both f)riinary and pyroclastic, were ■ LlmiBren, W.. '•.Mineral drp„«it,." .,lcGraw-HiU HcK-k Co., New York. N V.. igij, „p 017. 6J7, etc. ■■^putr and Carrey. Econ. ChhiI. vol. ,i, iqfi,^. pp. 68R-T25. lono '^''-'^■™'";"' "• '^■- "The Whitchorse copiOT Mt. Yukon Territory." Geol. Surv.. Can '^i' . pp. 21, 22, 23. (In this taso the dinochlore is clearly a prii-iary mineral.) ■1 100 encountered, pile.! up in a great succession of flows and in ag- "1- amfturt be.ls. over 5,0..0 feet thick, and covermg an •irea of over 1,000 square milt's. The various tvpes of basaltic rocks exanr>ined m thm scct.on can be considere.l only as samples of the f— J'""' '-^l^hough their unvarying composition is good testm,on> to the general homoRcneity of this great mass of volcamcs. Basalt Dykes. Basalt is rare as an mjected type, but a few dykes have been noted. They arc dark grey, very finely crvstal- '" ""under the microscope the essential minerals are labradorite and augite, with subordinate magnetite, and secondary-^chlor.te and calcite. The labradorite has the composition Ab.^n.o, and is in sharply crystallized, lath shaped, and tabular finely nlnec forms It forms about 60 per cent of the rock, averages 2 by O-O-l mm. in size, and is very fresh. 1 he augite has a violet Unge, and is faintly pleochroic. It is usualK fresh, bu hoc alionaly altered to chlorite. Magnetite forms individual ll\ and is often in parallel and reticulate strings of octahcKlra. Thrixture is intersertal, the augite in small equant grains filling the inirstices between the labradorite laths Labradorite and augite crystallized in part simultaneously, but the latter kept on forming after the labradorite had ceased to grow. Both in composition and habit the dyke basalt ,s clearly re- lated to the effusive basalt, and the dykes are doubtless the feeders for the flows, in part at least. Basalt Flan.. These flows are fresh-looking rocU varp . in texuire from almost vitreous to very finely, but distinctly granular. This type is of very --l^/'^f "''"^'-/";' ,:tnvi basalt porphyrite, makes up by far the larger part of the forma """under the microscope the essential minerals are labradorite and augite, with subordinate maKf.etite and perhaps olivine. lie rocks contain small amounts of residual glass, and the. ^ m a link with the vitrophyric type. Secondary minerals a c cZL, calcite, kaolin, limonite, h--uite epidote, and pn,.. ablv serpentine. The labradorite is usually in sharpK cr>. Szed. unaltered, rectangular laths, from 0-05 by 0-00. mm. 101 to 0-5 by 007 mm., finely ttvinncd after the albite law, some- times after the Carlsbad as well. It forms from 40 per rent to 85 per cent of the rock. Augite is colourless, pale greenish or violet, faintly pleochroic or not at ail. It is often almost entirely unaltered. In some rocks it varies greatly in size from 0-02 mm. to 1-5 mm., the larger grains being oikocrysts poicilitically enclosing chadacrysts of labradorite. The smaller grains are interstitial between the feldspars. Alteration of the augite, when present, is to chlorite, calcite, and finely granular magnetite. Augite makes up 15 to M) \kt cent of the rock. Primary magnetite (ilmenite ?) is in considerable abundance in some specimens, in single and grouped euhedral grains. The te.xture is in most cases interscrtal, but in some it is ophitic, and others exhibit both fabrics. In all cases a marked fluidal development of the labradorite laths is manifested, even in the poicilitic basalts the labradorite chadacr\sts in the augite oikocrysts being arranged parallel to the general direction of flow. Basalt Porphyrite. Several varieties of this type of How rocks have been studied, which vary only in texture. In the field they are black or dark grey, heavy rocks, differing in the amount of phenocrysts they contain, and in the granularity of the groundmass, which ranges from glass (forming the vitro- phyre, a variety described below) to distinctly, thouj;li finely crystalline. In thin section labradorite appears as a phenocr>st, usually accompanied by augite, in a gruundmass composed of the same minerals with magnetite (ilmenite). In some cases, badly altered grains, of the general size of the phenocrysts, are seen, which were probably originally olivine. The !abr.idi)rite varies in size from 0-25 mm. to 1-0 mm., and is fre(|iuntly equant, though sometimes tabular. Its composition is from Abs.iAnTo to Ab4oAn6o. Augite is generally smaller than the feldspar phenocrysts, and is usually e(iuant and euhedral. In many rocks the phenocrysts have a marked glomeroporph.Nritic tendency. The groundmass consists of labradorite and augite with magnetite, the feldspar being typic.illy lath shaped and often arranged in marked flowage lines, while the augite is RS^.-.-Wr .* . II i| 11 III IHMIIIIII llliill I |l III 102 usually equant and intersertal, indicating crystallization after flowage had ceased. Alteration varies in these basalt porphyrites. some being almost wholly unaffected while others have cloudy feldspar and chloritized augite. Decomposition is never comparable with that in the Etheline volcanics. In the thin section made from one of the basalt porphyrites collected by C. H. Clapp. several of the labradorite phenocrysts exhibited a peculiar regular mottling, the cause of which is not clear. The phenocryst best exhibiting this mottling is cut nearly normal to 010 and 001. The composition is AbaoAnjo (deter- mined bv index of refraction, optical character, and by the statistical method). It contains numerous inclusions of augite up to 0-3 mm. long, usually unk-r 01 mm., and generally altered to chlorite and magnetite. The peculiar mottling consisting of connected, rectangular or square areas, and forming a net work throughout the section, gives the impression of a crystalligraphically mter- grown substance. This substance has a slightly higher index of refraction than the rest of the phenocryst, and is probably plagioclase, more calcic than Ab«.\n,o. No satisfactory explan- ation of this unusual texture in labradorite occurs to the writer. Basalt Amygdaloid. Amygdaloids are of frequent occurrence in various parts of the Masset formation, and are most inter- estingly developed at T! n point, on the west coast where highly amygdaloidal basalts luive the cavities filled with chalcedony quartz, calcite, and black sticky tar, the latter a substance of great rarity in such a connexion. These rocks have not been studied in thin section owing to the unfortunate loss of the specimens by shipwreck, but their field appearance is that of the ordinary basalt as described above, modified, of course, by the texture. They are further treated of in the description of the tar occurrence in the chapter on "Economic Geology." A specimen of basalt amygdaloid, collected from a talus at the foot of a high cliff of flows on Tarundl creek, is a light greenish altered looking rock, composed of about 5 per cent ot 103 somewhat elongate, fluidally arranged amygdules up to one-half inch long and filled with chlorite, calcite, and common opal. In thin section the essential minerals are plagioclase and augite, both greatly altered, though with the habit of those minerals as in the other basalts. Secondary minerals are chlorite and calcite in large amounts, limonite, sericite, kaolin, etc. The texture of the massive portion of the rock is very finely granular and the alteration, in contrast to the other basalts, is great. A boulder found in the Baddeck river consists of a dark green, highly amygdaloidal rock, crowded with spherical amyg- dules of chlorite, some of them concentrically arranged. Under the .microscope, the original minerals of the rock are seen to be entirely altered and recrystallized to a finely granular mass of euhedral to subhedral epidote and chlorite. The amygdulcL jriginally filled with chlorite have been re- crystallized and are more intimately bound up with and grada- al into the solid portion of the rock. Not a trace of any j-.mary mineral was noted. Besides epidote and chlorite, limonite and probably magnetite dust occur. The alteration is, of course, extreme; and it is significant that the only cases of considerable alteration seen in the basalts have taken place in these, originally porous rocks. The high degree of recrystalli- zation in this rock, which is probably a surface flow, is evidence that hydrothermal action acted in an especially severe manner ; and the rock may belong to the Yakoun formation, though found in an area underlain by Masset basalt flows. Quartz Basalt. A specimen collected from the east shore of Yakoun lake is remarkable on account of the quartz it contains. It is a grey, dense rock. In thin section, labradorite and augite are the essential minerals, with subordinate quartz and magnetite. The usual calcite, chlorite, etc., are found secondary. The labradorite forms laths with irregular ends, averaging 0-4 by 0-05 mm. The mineral is so unaltered that only a little kaolin has been noted. The augite, on the other hand, is virtually all altered to a scaly and granular mass of calcite with a little chlorite. Quartz is found in equant, irregularly anhedral ^.iAJcs«■rs«&''«S!»wvv^^^."^•5^:i■'■"■ 104 grains, filling the last spaces left by the crystallization of the other minerals. Into these spaces the ends of the other minerals projected and are now surrounded by quartz. The quartz .s estimated to form nearly 5 per cent of the rock. Tachylyte. This rare' type, a glassy basalt, was found forming fragments in an agglomerate on the west side of Ship Kieta island in Masset inlet, and fragments were found in streams entering Athlow bay on the west coast. A large mass of it is reported to occur on the west side of Juskatla inlet. The tachylyte is a black, glassy rock, with a brilliant lustre, speckled with white, rectangular phenocrysts of feldspar up to a millimetre in size. j„.:f„ In thin section the phenocrysts are seen to be labradonte. about Ab,„An«,. in euhedral, equant. and tabular forms, quite clear and unaltered. Carlsbad twins are combined with albite twinning. A few phenocrysts of fresh augite are also preset.. The groundmass is a brownish, perfectly isotropic glass con- taining disseminated grains of a fine black mineral, probab y magnttite. and extremely minute, nair-like crvs^ probably feldspar. The phenocrysts exhibit a gloi- ^orphyritic ten- dency The alteration of this rock is very slight indeed, which is remarkable considering its unstable condition as a glass. Tuffs are abundantly repre- enter' on the west coast and are of several varieties, some of which are described in the part of the chapter on "Economic Geology" treating of the bituminous rocks in the Masset formation. Basalt Tuff. On Baddeck river, the Masset flows contain a number of bright, brick-red, intercalated beds, most of which are tufTs The specimen examined is a mottled, bright and dark red, very dense highly ferruginous rock, clearly of clastic origin Studied in thin section, it is seen to consist of sub-rounded fragments of dense and vitreous basalts, containing phenocrysts of labradorite closely crowded together. Fragmentary fresh andesine occurs. The whole rock is permeated and m part replaced by hematite, giving the red colour and rendering the rock almost opaque in thin section. iliarker A "Petrology for Students," Univ. Pre». Cambridge, 1908 p. 207. fddtg., J-'P., 'Ce^s Rock.,' vol. I, Wiley and Son.. New York. N.Y., 1909. p. 378. 105 Trachyte. On the west side of Harrison island, in Juskatla inlet, prospecting work has been done on a large mass of light coloured, variegated, dense rock, occurring intercalated in the basalt Hows and agglomerates, which form the remainder of the island. The rocks of the vicinicy strike north 45 degrees east and dip 70 degrees southeast, in some places slightly contorted, and the mass of light coloured rock is clearly intcrhedded with them- Where it has been blasted, 30 feet of the bed is visible with no indication of the total thickness. Mr. Arthur Robertson, owner of the claim, reports that the rock outcrops over an area several hundred feet wide, crossing the island in a southerly direction, so that the thickness and lateral extent may be con- siderable. The rock varies in appearance in the field. In general, it is light, creamy white, chalky white where weathered, and pale bluish or pale sea green where apparently quite frerh. A marked characteristic of the coloration is the reddish irregular mottlings hich extend throughout the rock in all directions, and make up varying proportions of it at different places. This colouring varies from a chocolate red to a light brick red. On joint planes are brilliant yellow stains of limonite. The rock shows various gradations in texture from very dense to fairly porous; and much of it shows a variable lamina- tion suggestive of flow-structure. The reddened areas mentioned above are to some degree controlled by this banding. In various parts of the rock are small cavities, usually under one-fourth of an inch across, and of no particular regularity of shape, which are lined with minute crystals and, in rare instances, spherical concretionary masses of chalcedony have been noted in them. Disseminated sulphides, like marcasite, are found sparingly. In general appearance the -^ck in the field is like a cherty sediment or silicified tuff, and its true nature was not suspected until a microscopic study was made. The silicified or cherty appearance of the rock is enhanced by a slightly vitreous lustre. Studied in thin section the rock is seen to be comoosed almost wholly of feldspar, which is apparently orthoclase. The texture of the rock is distinctly trachytic, and very fine-grained, the laths of feldspar averaging 03 by 003 mm. in size. They k 106 have parallel sides, and indefinite, irregular ends. They show parallel extinction; and crushed fragments were determined by the immersion method in liquids of known indices of refraction to have indices very close to those given for orthoclase. Scat- tered phenocrysts of orthoclase have been noted, up to 0- 5 mm^ by 0-4 mm. Besides orthoclase. a minute grain of a mineral that may be augite was noted in thin section, also small amounts of what appears to be pyrite, in very minute, sometimes cubic grains, frequently arranged in bead-like strings up to 03 mm. Viewed with a binocular microscope, the cavities are seen to be lined with tabular, clear crystals which apparently are felds- par. When these crystals, which are not over 0-25 mm. across, are crushed and observed with the nolarizing microscope, they are seen to be microcline, with exce-.ent grating structure, and enclosing minute reddish and deep orange grains of hematite. In these cavities, which are miarolitic in their nature, is also found a colourless, almost isotropic mineral with poor or no cleavage, and an index of refraction considerably less than 1-495. This may be sodalite or analcite. The texture as seen in thin section is also interesting. Ihe main mass of the rock has the typical divergent texture of the bostonites or trachytes, markedly fluidal in the slides studied. Sections cut from parts of the rock full of the miarolitic cavities show these to be of all shapes and sizes, ranging from a slight disturbance of the usual even-grained texture to a cavity several millimetres in diameter. These cavities are lined with an en- crusting rim made up of radial fibres, inside of which a vacant space occurs, or the space is in some cases filled with feldspar or the mineral noted above as being probably analcite or sodalite. The encrusting radial rims are probably needles of orthoclase or microcline. One or two instances of spherulitic development have been noted, as well as an extension of the radial rims into plumose growths. The minerals are almost absolutely fresh. The only decom- position noted was a slight oxidation of the pyrite in specimens near the surface. The reddish colouring of the mottled areas appears to be due to submicroscopic matter, probably hematite, enclosed in the feldspar. 107 The mode of occurrence and textute of this rock indicate that it is a flow, and not an injected type. In composition and texture it is decidedly of the bostonitc type. The name bostonite has been used by Rosenbusch' for a dyke rock, but the type occurrence, at Marhlehead Neck, near Boston, Massachusetts, is considered by some of those who are familiar with the locality to be an effusive and not an intrusive rock. In the absence of analyses, it seems l)est to designate the rock by the more general term trachyte, and to call attention to its bostonitic habit and probable composition. Where prospected, the trachyte is reported to carry values in gold. No free gold was seen and samples of the exposure were unfortunately lost. The occurrence of this alkaline rock in the midst of a great basaltic series is analagous to the bostonite found in the Island of Skye.' ORIGIN OF THE TERTIARY IGNEOUS ROCKS. The Tertiary igneous rocks of Graham island exhibit certain relation.ships that throw light on their origin, and on the history of the magma from which they were derived. These igneous rocks are naturally divisible into two series; the earlier Etheline intrusive rocks, and the later Masset effusive and explosive types. Some of the facts in regard to these Tertiary rocks are summarized below, and a discussion of them follows. In the intrusive rocks of the Etheline formation dacite has been found only as a dykerock, and never as a sill. Andesite forms both dykes and sills, the former in much larger number. Basalt has not been recognized in this formation, for all the basalt dykes that occur in association with it show marked affinities with the Masset rocks. The rocks of the Etheline formation are all highly altered types, differing in this respect from the Masset formation even more than their greater age would lead one to expect. The period of eruption of the Masset formation, which is almost ' RoaenbuKb. H.. "ElemenU der GeMelnslehre,' • Huket, A., "Tertiary Igneoui Rocks or Skye," 1910, p. 2«9. 1904, pp. 327, 239-290. 108 wholly basaltic, was separated from the earlier more si! 'c in- trusions by a considerable lapse of time during which the Skonun sediments accumulated. The Tertiary volcanics are lielieved to have origmated by pro(esses of magmatic differentiation in a sub-crustal reservoir, and from that source to have been intruded into the upper por- tions of the crust, finally reaching the surface. The facts given under the preieding hcailing are best explainwl by this hypothe- sis, which we may now _!aborate somewhat. The consanguinity of the various types of the Etheline in- trusives, which is evident from the descriptions given, indicates a common parent magma which seems to have been an olivine free basalt of felsic nature. This common parent magma is supposed to have differentiated by gravitative adjustment so that a gradational stratified condition was reached, with dacites at the top, underlain by andesites, in turn resting on basalts. This differentiation and stratification took place during the long period of quiescent subsidence during which the Cretaceous sedi- ments were accumulated. The movements causing the folding of the sediments disturbed the equilibrium of the magma chamber and part of its filling was injected into the roof. The intrusions began gradually, consequent on the slow but powerful forces do- forming the region and extended over a considerable period, as shown by the folding of sills and dykes with the Queen Charlotte series. The first material to leave the chamber was the upper- most dacite magma, and this was forced into the first cracks penetrating the crust. It will be recalled that dacite occurs only as dykes. There are a number of reasons for this: first, the marginal rock was the coolest or possessed the least degree of superheat and, therefore, was most viscous and incapable of penetrating to the surface; second, the silicic character of the magma would render it viscous; third, the first fissures may well be supposed to have been of less magnitude than the later ones; and fourth, the surface was at a greater distance in this early period of intrusion owing to a less amount of erosion having taken place. In the case of the andesites, the same causes oper- ated but in less degree; so we have many andesite dykes and some sills, necessitating a more superheated rock. The greater « 109 number of andesites is what would be exported according to the hypothesis of difTercntiation from a basalt or an auRitc andesite magma. The tapping of the upjK-r portions of the magma ihamber seems to have sufficed to relieve the pressures that tended to cause eruption; so that a quiescent prriod of considerable dura- tion ensued during which the Skonun formation accumulated. Then came an era of tremendous volcanic activity and explosions and effusions of lava took place in great numljer. During this period the main basaltic sub-crustal reservoir was in direct com- munication with the surface. It is thus seen that the various igneous rocks of the Tertiary period may best be explained as the result of magmatic dilTerr tiation by gravitative adjustment. This general explanation, however, does not suiilice to explain the exceptional alkaline trachyte associated with the basalts of the Masset formation; and it can only be said here that owing to its unique occurrence in the series, and its relatively small volume, it is apparently a local difTcrentiate, in, or near a vent. That it was near a vent is indicated by the tachylyte as well as the agglomerates found in Its vicinity. Surrounded as it is by enormous masses ot basalt the field relations of this trachyte alTord further proof that it is a differentiate of the basaltic magma. .ri'c- •H^r^:'^-<:- 110 cHAPn:R VI. STRUCTURAL GEOLOGY, HISTORICAL GEOLOGY. AND CORRELATION. STRb'CTURAL GEOLOGY. Foldini-. The structure of the Queen Charlotte series has already been discussed in some detail in the description of those rocks. A more general treatment of the structural features of the district as a whole follows. The pre-Cretaceous rocks are affected by a series of folds with a general strike of north 30 degrees west, correspon.hng with the trend of the islands south of Skidegate inlet. The general structure of these rocks is not wholly evident, as the CretaceouF and Tertiary covering obscures them, but there is good evidence that they are disposed in a broad, major anticline, with the above strike. The central part of this anticline is ocrnpicd by the Maude argillites, which are flanked on both sides by the overlying Yakoun volcanics. This general anticlinal structure is complicated by many smaller folds, especially in the less comiKJtent argillites of the Maude formauon. These thin bedded and relatively plastic rocks readily yielded to deforming stresses, and were bent into close, often isoclinal foWs. While the information is meagre, it is the writer's opinion that the fold- ing on a major scale was not as intense as might be imagined from a study of locally plicated areas of the argillites. These fine-grained beds, although thin, are remarkably uniform over wide areas, and, as already explained, allowed stresses to accu- mulate to a certain point, when zones in the argillites were in- tensely deformed, giving the close folding already described. In these argillites the type of folding is that termed parallel. In the massive, more competent volcanics. the strains caused shear zones and faults, instead of folds. The orogemc move- ments causing the upheaval and deformation of these rocks mani- fested themselves as compressive stresses acting in a direction north 60 degrees east, and may be correlated with the distur- Ill bance concomitant with the intrusion of the upper Jurassic batholiths of the Coast rnnRes. The subsequent ernsional shapinu of the uplifted mountain ranges of the? upper Jurassic caused valleys to form parallel to the folds, that is, with a genera! north 30 degrees west direction; and it was in these valleys, after their subsidence and invasion by the sea, that the Cretaceous sediments were ace umulate*. Erosion has now laid bare once more porti ss . yiiP!Pirt«rrB-Tv:i*i\fl»- 112 each deformation of the rixk» of C.raham inland. The earlict recKniee.! fault is the ..ne *hi(h forms the western bc.un.lary of the Queen Charlotte series at South jx.int m SkideRatc inlet. Thi. fault is dearly in evidence on the east Hide of the ix.int, where Honna conKl<..nerate is in close juxtarx^mtion to the Maude form- ation. prnvinK an easterly downthrow. It is not clear whether the fault is normal or revere-, but it is probably normal. The direction is somewhat conjectural, but the fault may well In; the same one that attecta the coal seam at the old C owgUz mme. and t ha« been so mapped. Cutting this fault and displacmg .t and therefore, later than it, is an cast-west break, the effects of whi;:h are plainly visible from Steep point to Lina narrow.. This is probably a normal fault with a northerly downthrow^ and in its westwanl continuation may pass through the marked east-west valley between the mouth o' Long arm and North """"in the vicinity of the mouth of Slatechuck creek there are areas of the Maude formation which bear relations to the later sediments that can be most readily explamed by the faults shown on the map. By this assumption of a fault block of the Maude in the lower Slatechuck valley the absence of the Honna conglomerate in this vicinity is explained. A fault with a general east-west direction crosses the south- east end of South island. It has a northerly downthrow, bring- ing Haida shales sharply against the Maude formation, and. therefore, may be of considerable displacement. The attitudes of the formation on Nose point and on the adjacent ends of Maude and Lina islands are best explained by supposing a normal fault to occur in the Channel between these islands and Nose point. This fault has apparently a direction a few degrees west of north, and a westerly downthrow of about 500 feet. ... • uu Faulting in the interior of the island is almost impossible of detection on the surface on account of the rarity of exposures. On a minute scale the flaggy argillites of the Maude formation are known to be extensively fractured, and minor faults have been detected in prospect openings at various places m the Haida formation of the Queen Charlotte series. r?KJKBN^ tlJ From the foreRoiriK description of the faults that occur there, it is appi«rent that SkidcKate inlet is an area of marked fracturing mostly east -w< -it in (iireciiiin, and wr i ronsiderable downthrows to thi- mirth. Kor this rcison the 'niet foritis. in general, a KcoioRical Ixjundary iKtwcen the pre-Cretaceous rocks of the southern islanosures major jointing cannot be distinRuished from minor breaks. A significant clue to the tlirections of major jointing is obtained, however, from the directions of the many dykes cutting the rocks. It may fairly be supposed that these dykes ibIe for the narrow trench which the Honna river now occupies in its broad valley. Since the close of the Tertiary, the area has been subjected to subaerial erosion which in a large measure shaped the present topography. I)urin;r the Pleistocene, the Queen Charlotte range was covered in part at least with an ice cap; and glaciers flowed from the range along the fiords of the west coast and also through Skidegate inlet, where strong glacial scouring has been noted. That ice occupied at least part of the lowlands also is indicated by the occurrence of *'■" '■; so many localities. The well stratified glacial sands an found in several places indicate lacustrine conditions du t of the glacial occupa- tion. There are some evidences of a recent uplift having affected Graham island. Xear the mouth of the Vakoun river, in a bank of stratified clay and gravel, numerous recent shel' were found, identical w-ith those now li'.ing below high tide le\el in Masset inlet. The highest position of the>e shells in the bank was from l.S to 18 feet above high tide. Dawson' dcscrilies .similarly uplifted shell banks at Xaden harbour a'^d on the .\Ianiin ri\er. He also^ mentions seeing terrace: videgate and Masset Tk'oI. Surv.. Can.. .\nn. Rept., 1878-r>), pp. 9+-').iIi. ' Lot. ctl. 118 inlets up to 20 feet above sea-level, but the present writer could not convince hini^ell that these were present. The very marked wave-cut benches seen in Skidesate inlet. Ma^set inlet, and on the west coast (Plates I and VIII B) which are now virtually at high tide lev. !, .aay indicate a recent uplift; though Dawson' considers them to have formed at this level owing to the pro- tection of *he rocks below high tide mp k by sea weeds. Arountl Sicidegate inlet were noted several of the heaps of recent shells mixed with soil, decayed sea-weed, and gravel, that are such a common feature of the Puget Sound region.^ These shell heaps contained numerous shells and many single and broken valves. It seems quite probable that the heaps represent an upraised beach deposit. CORRELATION. The following table of the formations of Graham island, compared with those of neighbouring districts, will show at a glance the relations between them. The close geological relations of Graham island and Vancouver island are well brought out, also the absence from this insular province of the upper Jurassic and Lower Cretaceous stratified formations of the Alaska province. 'Arnold and Hannihal. "Tw marine Tertiary stratigraphy of the north Pacific coast of America" Proc. Am. Phil. S<»-. vol. LI I. I'n.i, p. S^l . The name "Saanich" had heen applied (previous to this usage for a Pleistocene formation., to a body of Krano'H. Massut formation ■^konun forniat ion I'nconformity Basaltic Hows, tufit, and agglomprates. travels, sands and clays, glacial drift. Unconformity Cook inJct and Alaska paotnsula* Fonnation UtbobgicKt charactar Sandstones, contjiomerates, and shales, with marine foasils and lignite. Rcoeat volcank matarial. Beach and flood-plaio da-': poaits. Terrace gravelt 1 Glacial depoaiu. J; Basaltic Aowa a.^ tufft. Sedimmtary beds. Riheline formation Intrusive dacite and andesite. Kenai aeries Kenai formatinn liable sandstones, con- glomerates, shales, ^ntl coal seams. i-r ( relactruii Oueen Char- lotte scrieb Unconformity l-osftiliferous sandstones, shales, and conglomerates, with coal. Unconformity Sandstones, shales, and coals (Kutu island). Vnconformily I. ike the Kenai, but with sonic| marina shalca and sandstone. I ower Crtr.i< cous Gravina series; (Meaozoic ?) Kasaan Green- ( ungtomerates and shales.,, I'nconformity stone (Mesozoic ?) Intrusives ^nd extrusivea. Unconformity ' fT'*"'' j'-irassic \Iid'ii(' Jurassic I u tfer j iir:is*iic Ijiljer I riasair Lo'Ai r i rias.=iir Rathulithic in- tnisives, etc. Quartz diorite, etc. Coast Range intru- l>inrites, granodiorites, andi Naknek formation sivea (Probably ^-ranites. Jurassic) Chisic coc^kinierate. Vakoun furmation .Maude for .nation A^lomerates, tuffs, and flows I>ark :oioured, fine-grained, , thinly laminated fossiliier- ous aigillites, grading up-' ; wrH into tuffs and agglom- erate*. Possi! " ■ detrital I conglomerates ai .^ase. ; Chinitna shale t Tuxedni sand- stone. ; Granitic rocks. I PoqAyries and tuffs. Kamishak chert. Limestcme UmeotformUy Shales and sandstones with Am*Ua cntncoUt. Unamfet Naknek formation < '^ncbnierate, sandstone, ar- koae, and shales with andesitic Sows. Enock'on formation Unconformity ^ hales and sandstones with some! congtomerate beds. Puffs and saadstonea Uneoi^ormtty rbin-bedded cberta, Ui and shales, base not u, i*ti>*,n. ■ A. U. Brooks, U.S.G.S. Prof. Paper 43, p. 206. * G. C. Martin and F. J. Kacx, U^.G^ BuU. MS, p. 30. < F. W. Stanton and G. C Martin, Hua. GcoL Soc America, voL io, IM •CH.Chpp,GeoLSurv..Can..Mam.U,pp.36J7. w^t MUtMM tt Gnkam lOamd mi NtiffUmnnt DittrkU n\tf Famution Matuiuka vsUey, Aluka> Litholorkal character UtKOHfomiiy Fairb^oki qnadrtBgli, Ala«ki' Foniuiioo Lithola(icmI c''-rjcter Skseu river, B.C." VaacM..Tite. Shale and aaodatooe LimeaCoae l^iale, iandatnnc, and congtom- ent« i Carbonaceous shales, sand- j stone, aiid conglonierates. iSkeena .Sandstone and ahak jAndesttic greenstooe, tuflb, tg- glonierate^ and t^'ecoias; iliyoUtas. -r Shales, sandstones, con- glom<:rate, and coal. | I IlaieltCHi gnmp SooV-e and Camanah Conglomerares and sand- Sandstone, conglomerate, formations '■ stones, shale, and coal. (Oltgoccoe ?) I Nanaimo Conglomerates, sandst )n«8, Allison 'Belly Soft light grey aandatones. and shales, with coal | Rivery ? ChieBy dark stiales. llBenton ? Analcite pyrocla«tics. {|Crow5nest volcanics4 Chiefly greenish sandstones. Dakota( ?)fomiationj Kootenay formation Sandstones, shales, and coa seams. • Andesilc Bows and sand- stone, shales, and tuffs. Batbolithic and dvke Granodiorites, quartz intnisives. diorites, etc. ^Sicker series (Jurassic or Triassic). J Andesitic flows and l..?^:i schistose slaty tuf j. i ooa I and quartzoae sedin^> nta. {Sutton formation, Crystalline limestones, iiet- j Vancouver vol- amorphic andesites, and canics. i pyrodaatic rocks. Femie formation Dark shales with a (ew thir sandstone beds. Nitinac farmatioa ( ?; , voL to, IDM, pp. J»i-4ia > G. C Martin and F. J. Kati, U.S.G S. BuU. 500^ p. U. 17. >«W.W.LMch,Ti>tlfUiIat«r.GwL Ca^.,GuidabaokNo.9, P.2J. BJj • Carrta Kcnai Boca. ' L. k Prindk, U.S.G.S. Bull SM, p.34. • W. W. Leach, in^A. Surv., Can., Sum. Rtpt., 1910, p. 93. 110 CHAPTiCK VII. ECONOMIC (,k,oi.o(;y. The suhst.incc< to l)e cons. liTf I i.; (iixiisvini; tlu- cconnmic pcfiliiiiy of (Irahain island arc n i', li^niic, pilrolciini, oil-slialc, rlay, huildinK stone and liniuslonf, ai.il gold. Tlifsc m.ueriaU ari' treated in the (jrder gi\en. COAL. Coal, of Cretaceous age, is found in the Haida form.itioi: of the (Jueen Ch.irlotte series. The coal oreurrenees may lie grouped on structural grounds in two l)asins; the Ho.ina i)asin in the southern part of the island, .md the Yakoun basin in the north-central [lart. In the Honna h.isin. anthracitic coal is found at Cowgitz and in the Slatechu -k vaMey in the vicinity of Skidegate inlet; and coal of a somewhat similar kind occurs near V.ikoun lake. At Camp Anthracite a coal is found resern- hlinij hitutriinous in appearance, hut more like a low jjrade anthracite in composition. The most import.mt location in the Honna basin is at Catnp Robertson, where one seam of bitu- minous coal has bien exposed. In the writer's summary report for 101,?, pages ,S6 and 48. the statement was made that thi .-xposures represented out- crops of the same horizon, repeati- 1 by folding. Further work has m.ide it appear more prolnbie that tin- horizon of Camps Robertson and .\uthracite, which doubtless are on the same seam, is higher in the Haida formation than the horizon of the exposures at Skidegate inlet and Yakoun Like. Coal has been found at only one locality in the Yakoun basin, at Camp Wilson, and the co,d there is also liituninious. Material of a cocdy nature is recordetl from the south shore of Saltspring bay by Richardson,' and on the south shore of Skidegate channel,- by Dawson. These occurrences are in an ' Riclianlson. James. i'.nA. Surv.. Can.. Ri'pt. of I'roj;.. \'<72-'i, p. 60. - Dawson. G. M., C.col. Surv., Can., Rcpt. of Prog., 1878-79. X 120 area nmUTl.iin l>y the lower Jiir.i->i( Maiidf formation, ami tlie so-callnl coal in proii.iMv a larlionaivuiis >liak' baiil in these rocks wliich contain no coal. IIONNA IIA^IN. Co7i'<^itz ami Vicinity. Tlio first discovery of coal in llic Oiiccn Cliarlotte islands was niadi' In" a Mr. Dowiiie in 18.^0, ai ("owi;itz near tlu' luad- \vat(r> of Hooper ireek,' and in tX^.S a company was formed in Victoria, H.C, to exploit the dipo>it. At the reiiiust of those iiUercsteil in the coal, J. lines Richardson of the Cicoloi;!!-.!! Survey examiiUMl the propert>-, and his ai count may he found in the Rejiort of ''ro^re>s of the ( ieolo^ical Survey for 1872-7.^. At the present time llii' workings are c.ueil and obscured by under- growth, so that the followiiig account is largely t.iken from Rich- ardson's report. The measure^ (oii 'ng the coal are nearly virti<-al, .and the existence of laull.. . suspected. Three se.mis have been suppo^ed to be present, ami they .irc rather Itnticiil.ir in char- acter. In oiu' of the pros|>ect tunnels the co.il was found in cont.ut with tr.i|) rock; and tiie seam which was called K"i>d anthracite, increased from 2 to ?> feet, where it was first struck, to over 6 feet and, tcMiuote Richardson, "continued so for 60 or 70 feet. It then became mixeil with black shale ;ind ironstone for seventy or eighty feet, and in this portion the loal had to be separated by hand pickini;. The tunnel continued for about fift\- feet farther, but I could not convince myself that any coal at all was present towards the extremity. This bed is called the 'six feet M'am." " Apparently stratisraphically above this seam, and perhaps the same < ne re|ieated by faulting, are two seams as shown in the following section; I'cct IncliLS Coal. giK)(l antliraiite ^ Black arj;illaceniis shale -1 6 ro.il, ){oo(l anthracite called the- "tiiri<.> feet seam" 2 .'' lilack arnillactious sh.ilc, with nodules of clay ironstone. .11 " Grey trap, or it ni.iy Ix' altered sandstone 8 8 ' Dawson. G. M. Gcol. Surv.. Can.. Kept, of Prog., 1878-79. p. l.iH. 121 The (rial scams at this loc.ilitv arc not far .iliovc the under- lying V()l(ani( nicks, and it is probal)!.' that ihi- relationship is duf to faullinK. as clscwlicrc ilic coal occurs well aliove the haso of the H.iida formation. In apjMaraiK e the (oil foutid on the dumps i.. a semi-anthracite, .uid it seems (|uite unaffected l>y its lorty ye.irs' exptisure to ilic .itniosiihcrc. An.iKsi's arc (lui)ted on p.iKc 126. A coal seam was seen l)y the writer on \\\nn < rck, .ilioul a qu.irUr of a mile nortiu.ist ol the openinns on Hooper (reek. The se.im is iK/t well exposed. It dips at a hiyh allele, ,ind is directly oii thi line of strike of the coal hori/oii between Hooper and SlatecluK k (reeks. The co.il is anthr.u ilic in appe.irance aiid the seam is f.iirly dean. It is at least .S fici thic k, ,uid over M)() feet above the base of the measures. This M'.ini is cither a continuatiim of one of the H(M;pcr Creek orSlatechu the entra.,ce and apparently the lowest, but this apparent position is probably clue to over-foldinR, as the base of the measures is reached on Coal creek in the same j;ei!eral direction as the adit. To cjuote Clapp: "The seams are associated with slaty shales, usually carbon- aceous, intrusive into which are at least two sills of altered dacite porphyrite. Th. sills do not appear to ha\c broken across the bedding, and may have been folded with the siiales. In the ' Clapp, C. H.. Geol. Surr., Can., Sura. Rept.. 1912. 122 li'nmh iif tin- 'tiiiiniT tlif im asiiri's ari' iiuulMMl in a hliarp -.vii- I'liiU' with a inrrt -.iHiiiilinn liroa\ir'.c I iiil.!«. The A -lam i- --iN Ifi l tliirk aiul coiisisis nf a soitu-what tru-licil fiial, wlii'li li >^ ilic ipiKMrani I" of iH'iiu' uraphitic Slaty ifiale roof /ft. 2 in coal Sin slaty sf>^le (not namplpd) 8 in coal Srt sidty shg/e (not sampled) I ft 2^ in coal S'aty sliale floor Slaty shale roof I ft 'Oul ■y sisty shale ;_ (not sampled) j in bony coa. (not sampled) 2 ft 4 in. coal Slaty shale floor Geolo^ica/ Survey. Canada I- ii;uri: 11. Sictiiins li and C *,inii cxixjsi'l ill tiiiinul of Uriii^li I'.ic lUr t'o.il t'oiiiiwny, >wtii)ii t, township 11, Cir.ili.tni itilanil, I' ( . Tilt' \\ stam is 5 fl. U\ in. thick, and the C soam is 5 feet thick. The coal from them' seams is not ^really criisheil." Detaileil section- of thcM' seams are i;iven in Figiiri' 1 1. In appearance the coal is of two prin, ipal ki;i(ls: a dull, somewh.it histreless v.irit'ty, which is crushed: and a tirilliantly black, hard, anthrac itic '.ixikini; niateri d. The tv\o varielit> form alternating; layers. Some of the hands of brilliant coal which are up to 3 inches thick possess a rude parting in sensibly parallel 12 < p! int -, .It riflu .iiik;lrs to the lniMiiii;. Tin -f p.irliti^' p!.in',il( T miljui.'rpliini lli in nrilin.ir\- .irilhr.K itc. It is ithniit (|ni--lii)n cli^.ly .illiiil u> .uiitir.iritr, Init his not 1)1 111 nict.inMrpliii>((| t'p m-arlx I'lr -l.itcs ■ lu liv uriinstonc-.. J'oiir v.iriiiiis of tlir MJuiiiuito an- note.!, of (litTinnt (Ui;rit> of piirit\-. wiryin^ from nearly jiiirc rarhon to rarlionaci'ous sl.it<', lno>traii/itl coiuiuilrs that s(hiin;:itf is an cxircnii' niinilii T o| ttu' loal striis, iiitcrir.KJiatc httwi'cn anthra- litv and ^'raphitc, and from its propirin s, whidi he discrihos in detail, he plicc^ il ncircr nra|ihitc than anlJiraiitf. The Ciraliam Island coal is also an "lAtrt aic momlptT," and is doulilKss also interniediali' In t ween anihrai itc and i;raphito; lull, imlikc- srlumgilf. it is luanr am'iraciti' than Kraphiic, and nia\- he rt'i^arck-d a> a coniifi tint; link hctwci'ii anthraiito and sdiim^ite. Altllou.nli intermediate between anthracite and scliiniKili', the cc ' is closely related to both; and while perhaps deser\in!^ of a specific name, the writer prefers tc> wait until more detailed tests are made of the substance.* Analysis 11 on pa^e 125 gives the composition df this m.itcrial as determined by proximate anaKsis. One of the specimens of this coal collected from the dumii exhibits an unusual and interesting; texture. It consists of coin- I StlltZLT, O. Dii' wirhlisMcn laqrrslatt^'n dor Ni^ht— Erie; llcilin. 1114. vol. i, p. 171. ' .\5 illiistnitnl hy spciimens in the collection of tin- .Massachusetts Institute of Technology, Boston. ' Inostranzell. .X. \eue« Jalir. IKsn. Hii. I, pp. ur-W4, and IW(>. lid. 1, pp. <)2-g.i. ' Specimens of this coal were in the ixissession of Mr. W. Fleet Robertson at the time of the visit of the international Ci-ological ConKress to \ itoria. B.C:., in l>'H. Some of the viuling German and Russian seologista when ihown the coal said it reaembled schuntiite doiely. 124 pressed and folded irrejjular layers of hard, brilliant coal, alter- nating with layers whose appearance varies. Some of these are wholly dense black, lustreless material, in sharp contrast with the bright variety. These dead black layers have a gradational relationship into the brilliant coal, and it is in these intermediate bands that the peculiar texture is seen. The intermediate layers consist of spherical grains of dull black material embedded in a matrix of the brilliant coal. The spherical bodies average about 2 mm. In diameter, and are occasionally rod-like in shape. The relative amounts of these bodies and of the matrix of brilliant coal vary; the spheres are usually closely packed together, and grade on the one hand into dense layers of dull coal penetrated at the margins by films of bright coal; and on the other, rather sharply, into the layers of brilliant coal. In order to determine if possible any structure that the spheroids might possess, highly polished fragments of the coal were examined with the aid of a metallographic microscope used for examining opaque substances by reflected light. No particu- lar structure was visible even with the highest magnifications. The dull spheroids were seen to contain minute irregular specks of bright coal embedded in the dull material. In various f)ortions of the surface examined, the bright patches increased in amount, and formed ramifying veinlets, marking off the surface of the coal into circles of dull material and intercircular areas of bright coal (Plate X\T B). The composition of the brilliant coal is given in analysis 1 1 on page 125 and, as already stated, it is that of a rather pure anthra- cite. The composition of the duller bands and dull spheroids, as shown by blow-pipe and qualitative tests, is that of clay iron- stone or ferrous carbonate mixed with carbonaceous matter. The iron carbonate probably was formed by the iron of the ferruginous solutions from the surrounding basic igneous rocks being precipitated as ferrous carbonate by the carbonaceous matter of the coal seams, then in process of accumulation. On account of the abundance of carbon, siderite, and not limonite or bog iron ore, formed. The peculiar texture is regarded as being of inorganic and also^of secondary origin. It is supposed that while such chemi- 125 1 S3 I E 3 1 ^^ r^WOO ^ O (Nf^ O <^ § r^<^ X-^^^ fN o t^ (N ^u^ -f. •* O ^ i^j (^ o X g iClOOOf t^ tN lO trir^ •t ^ r^ O 'f »^; *^ O O 0 r^ 00 »^ 00 8 u - u S e 1-8 u ^3 U 3 £ --a ^ 15 -a 5ij:^ ■s 3 t/1 o u •- ~ « '5 c|f:| ^ t 4J . o • = §^ tn O = ^15^ : — ^'^ ^ - J. ■ n-^ ■7^'-' 13 & " ^ _- t^ rsi •-"■ "^ 6iO /• Oil 'oxa: ft, i E g •50 •2^ o Sii" c H ^ ui o t- 4J I^ C "^ = T^ " ? 3 , )X « -■ 5 Ep - Si^ ' to '.0 SO ■ o .St) a; £ ~ x-io 126 cal and [)hysical changes were taking pkue in the arcumulatcd viRctahle matter that raiiscd the fdrmation of anthracite, there was a tendency for the pure carbonaceous substance to separate from the iron carbonate. This separation took place by a sort of concreti(Miary action, causing the clay ironstone to segregate in globular forms. Camp Kobertsnn. Location. Camp Robertson is situated in the western part of section 20, township 5. It is distant U miles from Queen Charlotte, is omt U miles from Camp Wilson, and about 3 miles from Yakoun lake, in each case by the trail. The first prospect- ing work of value was done in the spring of 189.?, and prospecting has been carried on at intervals to the present time. A number of oi)enings are the result of this work, and the coal is well ex- posed. A topographic map of the vicinity of Camp Robertson is given as Figure 17. Straiigraphic Position. The measures in the vicinity of Camp Robertson in which the coal seam occurs, are near the middle of the Haida formation, about 200 feet below the fine- grained, massive sandstone of the uppe; Haida. A good section of the lower Haida is obtained on Wawa creek from the trail crossing down to near its junction with Brent creek. Sections showing the central third of the formation are exposed on Falls and Anthracite creeks, south of Camp Robertson. Coal Openings. The coal is exposeil in a number of pros- pect shafts, slopes, etc., the location of which is shown on the accompanying l-rge scale map. These openings were made at various times from March, 1893 to the summer of 1913. A careful e.xa.iiination of the more important ones was made and two are illustrated in F .,ares 12 and 13. Coal Scam. In various public and private reports, the number of coal seams at Camp Robertson has been stated to be from two to three, and the estimates of the thickness of the individual seams also vary. In the investigation now reported on, the writer had the pleasure and advantage of the co-operation of Uean Milnor Roberts; and our careful measurements and ex- aminations have proved beyond rea.sonable doubt that there is only one coa! seam exposed in the present openings. 127 O ■7. u. 128 tr" — ■» a" i' 'I '/III. '//)/e ne Coa/B' C/ayS' Hard bone 2' Hard imp. Coel 3" Grey sha/e 3" DipSS" Level of drift Geolo-kical Survey. Canada. Figure 13. Sketch of folded coal seam, No. 1 shaft, Camp Rol)ct^son. Only the up[)er portion of the Rol)ertson seam is here shown. 129 K'li ii" 3 ini I • *J ^ 5 » ■ ■?.* I : ^ i -as ?r ^ v*^ ♦ VtV-'-^'^* 1 to •*! V * A n ii U iJililil^ H^IKtllf6 :u;lCi|:l o ^ yi r. ■~i ^ X .. - cir =0 y. ^ j: ■ c .H - £ O 1) ^ li IM — r u ■-> = -5 a c >_ - o o tdo r' ^ •ill i . c '^ j: >- ^ /^ S = o . •- *-> tc o U. r»; = ^ ri c -: i^ — c « S^ :2 s = s 8|a .2 5 c a i JS j: <^i r o ^ „ CJ c *— J ti = i,i V C r! (A i - u -■ = « 4-1 130 This seam, of which several complete and partial detailed sections are gi\cn in Figure 14, averages about 8 feet thick; and its total coal content, in several separate layers, varies from 2 feet 3 inches to 3 feet lOj inches in the sections measured. The scam is characterized by variation in detail in the superposition and relative amount of coal and impurities, but there is, never- theless, a marked similarity between the various sections. The floor on which the seam rests is grey or brownish grey shale, varying slightly from fine to coarse in different openings. The shale is soft, massive, and not laminated, breaks with a blocky fracture, and in places carries veinlets of calcite up to one-fourth of an inch wide. The upper surface of the shale, on which the lowest band of coal in the seam was deposited, is slightly wavy and irrc;,'lar. The coal parts cleanly from the massive shale, and the contact is a little slickensided. There is not the slightest appearance of underclay, and no trace of rootlets penetrating the floor. The coal has in small degree an appearance of dis- conformity with the floor, in that it fills up the minor irregulari- ties and then builds up an evenly laminated seam. The lowest band of the scam itself, which consists of 6 to 8 inches of bright, clean, somewhat crushed coal, is the best looking part of the seam, and this appearance of superiority is borne out by the analyses. This band is very constant, and appears in all the sections measured which reach the floor of the seam. Above this coal are alternate bands of brown and grey, fine day-shale of varying degrees of hardness, together with layers of dark brown or black, hard, tough, fine, carbonaceous and siliceous material, termed bone. With these impurities are various thin seams of coal, in places impure and bony. They are lenticular in form and can be only approximately referred to a general position in the lower part of the seam. In the lower part -^f the upper half of the seam is a constantly reappearing coal bench, averaging about 25 inches in thic!:ness, and Cf'>icai Sl. Scdi'e of fvet . ^_.A Figure 15. ^' rtical section through .\—.\' on right wall of open-cut (see I igure \b), looking north 70 degrees west. Ilhistr.ites typical occurrence of glacial drift resting on cleanly eroded surface of tjed- rock. No coal blossom is found in the drift material near the outcrop of the seam. Ji o o 1 hi / /ope 'VO J ee figure iti ) Scale of feet ■go POO 300 ^oo sgo Contour internal , lO feet '■oc'c j^'cj/ %,r^ey . Canada 10 Figure 17. Camp Robertson and vicinity. 134 1 O f*i r-i i/^ s ^ to lO 8 r* »0--Q0"0 8 J^©- © c c o ^ >r, 8 ^ " - - ^vOo •-^ -^ O* — r* 8 ^^4'^ fN (N '^ ©* 8 "■ ~ 1 fN O ^ -^ 5-^-3 JC ^-S J?^-= » !: C .« '/) -1 s: ^u. < x f$'H a 35 15 u e 8j- Ow. • o 1 I I J e § 'la Co u ■(J it -> a '^ Ml •S *: -o fe" = -| § ^1. ;:SJ5 JO Ju r* ^_, S ^ o' 5 « 5 «* 2 — .,2 .U .G-- '^ u: i/iH li =0 _ •SB o fl i'.h "tfc !,< e- _ o « ! -^^ B •=a' ii n ^ t 2«" O *— in '•0'*'= ti-^ «; ■o — .t: ~ rt , s: f « cl ■T^ <-' ~ «i ^ *- O^ V.'^ — l n! c ° . " £ ^ ='-5 .'5 -■ « jT 2 * _; o w 2 ai >• *. 5 _ ai ■ fs"'- I — ^ -S c °— 3 U o OS j: K = re = ■^s • - • p I 2-; as = c ° u^ as 135 Notes on Mining. The tunnel and slope, Figure 12, give an opportuniiy of judging ns to the qualities of the seam for mining puriosos. U.mIlss the whole seam is mined and the prod- uct washed free from dirt, the coal to be depended on is that in the so-called 25-inch bench, in the upper part of the seam. The lower 10 inches of this are noticeably the better, and more free from bone, some streaks of which occur in the upper part; but the good part of this 25 inches cannot be mined separately. From the bottom of this bench, at least 40 ' iches must be mined above to the roof, which would readily stand, with props and lagging every + or 5 feet. The roof holds well, and nowhere in the tunnel it had sagged more than one foot. No caps are bent, and there is little or no weight on the lagging, except for occa- sional spalls due to slickensiding. Pillars in the seam could doubt- less be robbed with safety, as the roof now stands 8 feet wide rib to rib. There is no slumping from the sides, nor any trace of swelling in the floor. The condition of the coal is the same in the portion under water as in that exposed to the air. The coal is as firm on the rib as at 2 feet in, and evidently does not carry any extra weight of roof on account of the openings having been made, as the roof supports itself right across. Water comes into the opening only through occasional joints, and it is probable that a mine on the seam would be dry and perhaps dusty. Structure. Althc ugh only exposed in the streams and pros- pect openings, enough outcrops have been observed to allow of the general structure of the rocks in this vicinity being made out fairly accurately. Wawa creek flows along an anticlinal axis, on which close local folding accompanied by some overthrust faulting has taken place. The compressed anticline exposed in the northwest and southeast walls of No. 1 shaft is sketched in Figure 13. The axis of this fold may be traced in the roof of the drift from this shaft and is seen to bend in a flat S curve. It is quite possible that minor faulting further complicates the seam. In the opening shown in Figure 12, consisting of a tunnel, slope, winze, and raise, it is shown clenrly that the two apparent seams are parts of the same seam repeated by faulting. The geological section sketched in the figure is well exposed on the northwest wall of the tunnel, slope, and winze, and requires little hV. explanation. Tb'- width rf t' l)ri)ki'n ground has do'ihtl > invi-!■'■■ is evidence of the intru>ion ■ novement had ceased, The ' )ver part )f the downthrow coal '^nch 'esting on the "' thy of notice. J It a sharp canoe- 1 robably about a mile '.houfiht not to cxcci-d -.ures are not wt II cx- ' the high ridge near Yakoun lake is a tiat syncline, modified bs low, undulating folds. The approximate ixisition of the outcrop "I the coal Ijearing horizon in this syncline is indicated on the map. Camp Anthracite. Location. Camp Anthracite is situated on the creek of the same name, an eighth of a mile above the trail crossing, -md about r. mile southeast of Camp Robertson. Stratigraphic Position. Camp .Anthracite is probably at the siime horizon as Camp Robertson, near the middle of the Haida formation, but apparently nearer the base of the massive sandstone of the upper Haida. The opening is an adit on the right bank of the creek driven for 4.1 feet across the measures. The roof of the coal seam is cut at 12 feet from the portal, and at this point a drift goes 30 feet southeast in the seam (Figure 18). Coal Seam. The seam at Camp Anthracite bears a resem- blance to the one at Camp Robertson, and is with little doubt the same. It is 9 feet thick, perhaps thickened by minor faulting, and contains several bands of coal, 4 feet 5 inches in all, separated by bands of shale and bone. Next the floor there is a 4-inch layer of crushed coal, as in the case of the seam at Camp Robertson. The roof is a medium to fine grey sandstone. The seam is illustrated in Figure 19. a S 6 Poof IS f/ne ^''cy sandstone Cob I, greatly crushed and slickensided /Z" 8'Coaty shale a'Shale 4' Coaly shale 7'Shale lO' Shale Coal crashed and slaty Q" Coal ye" Coal i*' Coal, Impure 22' Coal, good I' Coal and done 6' ^^ 4 "Crushed coaly shale 20 'Brown slick, shale Coal, crushed f |H Total 90^' Total coal S3 *♦' In 6 seams Scale ofJnches_ ^ ^ lO /ji ep M Geolo/^ical Survey, Canada Figure 19. Camp Anthracite, section through coal seams. 139 The analysis of the coal collected by the writer was made from a sample taken from the 29-inch bench in the lower part of the seam; and, except for the low percentage of volatile matter, rescml)les the analyses of the coal from Camp Robertson. In appearance the coal is crushed and rather slaty; it is bituminous in aspect, and in no way resembles anthracite. The low volatile matter is ascribed to the inlluence of tiie dykes and sills of ande- site and dacite so prevalent in the region, and a thin sill of vol- canic rock is exposed in the adit, beyond the coal seam. In the sandstones and shales underlying the coal seam there are several thin streaks and seams of coal, none e.xceeding 4 inches in thickness. They are quite unimportant as economic factors. Analyses of the Coal from Camp Anthracite. Water 5-69 7-83 42-10 44-38 1-52 8-69 80-07 9-72 2-1 Volatile matter 7-59 Fixed carbon 68-25 Ash 21-31 100-00 100-00 10000 Coke 86-48 (Noncoherent). 1. Tunnel, 20 {eet in from mouth. Collector J. D. MacKenzie, analyst F. G. Wait, Department of Mines. 2 and 3. Collector W. A. Robertson, analyst G. C. Hoffmann, Geol. Surv., Can., vol. VI, 1895, p. 13R. Structure. The measures are considerably disturbed in the immediate vicinity of Camp Anthracite, and the structure has not been worked out in detail. In the adit the measures are seen to strike north 32 degrees west, and to dip about 85 degrees southwest. This high dip is only local, however, and is probably 140 due to minor faulting, as a short distance up Anthracite creek, the massive fine sandstones of the upper Haida lie flat or at low angles. These beds form part of the large, flat syncline already mentioned as underlying the country west and southwest of Camp Robertson. Yakoun Lake. Location. Yakoun lake is situated in the southern part of the island, about 3 miles from Camp Robertson, and 14 miles from Queen Charlotte by trail. Near the southeast corner of the lake, where it bends sharply to the west, some prospecting has been done, and about 2| miles by trail south-southeast of that point Camp Trilby is located. Straligraphic Position. The exposures in this section of the island are few and little time was available for their study, so that the stratigraphy and structure have not been worked out thoroughly. From the data available, however, it is probable that the coal seam southeast of Yakoun lake occupies a narrow, north-south, closely folded syncline, pitching to the north. It is separated from the wider, main syncline of the Honna basin by an anticline of the older Yakoun volcanics. The relations are further obscured by Tertiary volcanic flows, but the areal rela- tions and the structure are believed to be essentially as delineated on the maps and sections. The coal seam is apparently not as far above the base of the Haida formation as it is at Camp Robertson, and the coal probably represents a lower horizon. It is fairly certain that the coal of Cowgitz, Slatechuck, and Yakoun lake represents the same horizon. Coal Seam. The opening nearer the lake is an adit on the left bank of a small creek, driven south 60 degrees east for 50 feet across the measures. In it are exposed black carbonaceous shales, cracked and slickensided, containing lenticular veinlets of hard, altered, coaly matter one-fourth of an inch thick. At about 40 feet in from the portal a 3-inch seam of anthracitic or coky coal is exposed. Above the adit in the creek bank a 4 to 5-inch seam of altered coked coal is exposed, probably 141 the extension of the 3-inch seam in the adit. Just outside the adit are impressions of small tree trunks in black shale. The coal itself to some extent resembles the material from Cowgitz and Slatechuck valley, but instead of being dense and heavy, it is porous and light, of a coky, rather than of an anthracitic nature, and with a lustrous, jet black colour. Some of the coal shows well marked columnar structure, the individual columns being about the size of the lead in a pencil and arranged normally to the bedding. Camp Trilby, the other locality near Yakoun lake, was not visited by the writer; but S. E. Slipper of the Geological Survey, who visited it, states that the occurrence is similar in a general way to that just described, though he was unable to carefully examine the workings. As in the case of the occurrences near Skidcgate inlet, the metamorphosed condition of the coal is ascribed to the heating action of dykes and sills of the Etheline volcanics. Sills are found in proximity to the seams and there are doubtless many that are not visible. The coked appearance of the coal is strong evidence that direct application of heat caused the metamorphism. Structur:. In general structure this coal basin seems to be a close folded syncline, pitching north. The opening nearer the lake is on the western limb of the fold, and the measures there dip steeply northeast, while Camp Trilby is situated on the eastern limb, and the rocks dip steeply southwest. This syncline is in part covered by flows of Tertiary volcanic rocks. Extent of the Coal-bearing Horizon. The accompanying areal map shows the supposed outcrop of the horizon of the Robertson seam, dchnitely located only at Camps Robertson and Anthracite, and elsewhere traced by means of its relations to the massive sandstone of the upper Haida. Away from the high ground on which these two camps are situated the outcrops are few and in certain areas lacking, so that the location of the line representing the horizon on the map is based, along portions of its course, more on inference than on direct evidence. The line shows at least approximately, however, the area which is underlain by the coal horizon. The 142 sections, constructed from surface exposures, indicnte that the probable depth of the coal horizon is not great over a consider- able area between Camp Robertson and Yakoun lake. The probability of a coal seam being found nt this horizon throughout the Honna basin, remains to be considered. The evidence on which the conclusions are based will in part he sum- med up later. There appears to be no good reason to expect that a seam of better quality than the one now known will be found. The measures on the whole arc variable and made up of hastily accumulated material; and the coal seam bears evidence of rapid changes in conditions of deposition. These conditions in the Honna basin do not appear to have been favouiable for the ex- tensive accumulation of vegetable deposits. The finding of coal scams in various localities, already enumerated, in different parts of the western and northern portions of the Honna basin, is good evidence that a single seam, or a series of overlapping seams occur there. The western portion of the seam or seams has been so altered by volcanic agencies that it cannot at present be econom- ically mined, even in the few localities where the coal is of sufficient thickness. About Camp Robertson the seam is at its best as far as qual- ity goes, but the structure is complicated by folds and faults. Between Camp Robertson, Yakoun lake, and the ridge surmount- ed by Mount Etheline there is a considerable body of coal which apparently is fairly regular in its structure; but, from the char- acter of the seam at Camp Robertson, the quality of this coal cannot be expected to be high. The question of the extension of the Robertson seam down the Honna valley is a difficult one to answer. No trace of the seam has been seen on any of the creeks in the territory in which the horizon outcrops, except on Honna river, where some coaly shale occurs. The massive sandstones of the upper Haida do not extend down the Honna valley, and in this valley and on the west shore of Bearskin bay the upper half of the Haida formation is shaly and thin bedded, and more fossiliferous than around Camp Robertson. The evidence is unsatisfactory because the actual conditions of the accumulation of the coal are not known; but conditions of deposition were different in the eastern part of 143 the syncline and, apparently, deeper water conditions prevailed. It is scarcely possible to draw safe conclusions; but the prob- ability that coal was not deposited in the southeastern part of the syncline and that the Honna valley and Maude and Lina islands may be barren of coal seams cannot be ignored. This hypothesis should not be acrcpied as fact, however, and the careful prospecting of the small eastern tributaries of the Honna river is recommended. YAKOUN BASIX. Camp Wilson. Location. Camp Wilson is located on Wilson creek, in the N. W. J, sec. 25, tp. 7. It is distant over 11 miles from Camp Robertson and about 20 miles from Queen Charlotte by the trail. A trail about three-fourths of a mile long leads from Camp Wilson to the Yakoun river, which is navigable for river boats at most stages of water from where the trail meets it to its mouth at Masset iniet ^2 miles distant. Stratigraphic Position. The strata in which the coal seam at Camp Wilson is found belong to the Haida formation and the seam has bten found by boring to be about 400 feet above the base of the formation. The rocks in this portion of the Yakoun basin are on the whole coarser than those in the Honna basin; and are composed of more angular, less sorted debris of the Yakoun volcanics. Coal Openings. The coal openings at Camp Wilson are three in number. No. 1 opening, on the right bank of Wilson creek, consists of an adit on the seam for a distance of 50 feet from the portal. At 8 feet from the entrance a winze 11 feet 6 inches deep gives access to a drift on the seam. From the winze this drift extends 20 feet south, and 24 feet north. Near the end of this northern portion a narrow crosscut exposes the full width of the seam. No. 2 opening is a shaft 14 feet deep from which a drift runs south on the seam for 20 feet. Ks'.o}s>: o V =1 ■o e s " o ct 8 * ^1 II c c3 ,^ X 'x ^ w "■' - <^ ^- . w ^i ^ u c t-. 3 ri .::? Hi •-4 VO i 145 No. 3 opening started as an adit, partly on the seam and partly in the glacial till, but with the increasing dip of the coal the adit developed into a slope, as shown in Figure 20. Coal Seam. The Wilson seam varies from 4 feet to 18 feet in thickness where measured, but it is not certain that the full thickness is exposed where the smaller measurement was obtained. It is certain, however, that the seam is of varying thickness, and that the maximum figure given above does not represent the true average. The floor is a green, fine to medium-grained sandstone, con- taining scattered, well rounded pebbles up to an inch in diameter. Under the microscope the sand grains are seen to consist of rounded volcanic fragments, with quartz and decomposed felds- par grains, in a calcareous cement. The scam itself, of which a diagrammatic section is given in Figure 21, is best exposed in No. 1 o|)ening, and was there sectioned and sampled. It is divided into two benches by a 5- inch band of soft, grey sandstone, occurring about S feet above the floor. At the base of the seam are usually found lenticular bands of granular, yellowish-grey, soft clay shale; but in some places the coal rests directly on the sandstone, or is separated from it by a layer of bone or by a bedded vein of calcite. In other places, bands of the same soft, plastic, clay shale occur in the lower part of the seam. The lower bench is dirty and of inferior quality, as shown by the analyses of the coal. The upper bench, about 12 feet thick, is composed almost wholly of coal in several layers, not all of the same quality. The upper part of the upper bench is crushed, dirty, and poor looking, and the analysis of this fxjrtion runs 37 per cent ash. The roof of the seam is a greenish, medium-grained sand- stone, more pebbly tha?! the floor, and in places almost a con- glomerate. In this ojjening (No. I) the seam shows no evidence of local thickening due to folding, the laminations being continuous and even; but a slight amount of thickening due to faulting occurs. The type of faulting is illustrated in Figure 22. The seam shows strong, continuous slickensides, parallel to the bedding, which are probably due to slight differential movements caused by the fioof p^htiiy V c<»/rs/'c«)«" Coal I- Coal V CotI If Coalhl'<:l')ir Coal(cruslvd}6 Cc.il 9- Coahsihyl'l' I Cam/ (fair) II Co.:t/c^3- Coan6ony)^H^ Coal ev Coal ir Coal (i'ony)S' Coal II- Coil 8- Coal 2' Shale *' i hale a' Coal 10- fyl'ghtly bony > Coal 4' (slightly cony} Coal 5 Coal a- Coal I • ioel 14' Coal r Shale r Shale If ^ri^Ca/ra S' Shale f bhale a' Bonr 2' Bone I ■ ihalal' Calcita H' Bone 3' a^j.i cslc.te <*' ^•'i Sam/stone .:vi floor Total coal leVV Geo/Q^cmf S : i?? : '^l jj c *< £5 mm \r, 3 t ■^ #- : •£» '^i :r OC X X 1/^ to ) O C — I ~ > 4_ o 11 :i; 3 S3 o « o CO u fl O ■« t w' d ^ ^ C -J r 3 ~ -2 -^ - = ? I 1 "I w .5 . S '■ ^ c ■ ■ c r^ ' • a. ,X, ■ ■' .5 i ^ - — ♦* c ** C «j ,M . -J 'V ;/ c y o - i '^ J < J > s? "^ » j| e^^o 2 at u Q - U S — - o - o r U BW c - .., .U .U i i 3 3 > I 1 -5 3 o Sp i« ■•'■ 5 ^ 2 5 .as &A U C all 1 1 I '2 J^t ■r s« o . . IS''- " « B ■" B u-i 1!^:: V B 1/— ' a^ ?• 4j a. = >,5 n 5 So . £ .u - - "t a: H « 5 2 (J ii -EC S3 u .^ ai: B I 3 .S «' B _-o.S w.'3'o oo - £ .1 .H| - so 151 20 shows the antii linal nature of the seam, and Fintirr 22 some of the small f.rults Men in \c, 1 oinninK. At tlit- .ml df the adit at No. 1 ofxiiin^ the -Awm is cut olT by a H')rth-!«)uth tault, and in No, 2 ojx-innK the seam w also rut off by a fault virtually on the strik' of whit li the details are not completely worked out. An InterestinR rase of the swelling arxl lotal minor I. I ling of a coal seam due to ex| .^ure to weathrrinK am nts is se«-'i in No. 3 opening, shown in Figure 20. Most nl the tlii( kenin^ an I contor- tion of the lenses ot white d.iy and of the seam as a wholi .ijtpears to be due to tlu- expansion of the seam caustt! \i\ the ai tion of surface water. Extent of the Coal-Bear ing Horizon. From the data obtained by boring at Camp Uiisoti t i: known that the coal seam occurs about 400 feet abd prospect openings were any of the above fea- tures seen. The high percentage of ash in the coal, e%'en of the cleanest type, is to be recalled. The facts given in the preceding paragraph jjoint to the conclusion that much of the vegetable matter now forming coal in the seams was accumulated by transportation, and did not grow directly where now found. While much of the surrounding terrane was doubtless hilly, a considerable extent of land immediately bordering the areas of sedimentary deposition was probably low; so that while the vegetation was accumulating, sedimentation from adjoining areas was largely checked. On these coastal lowlands, plants grew in profusion, and in part contributed theircjuotatotheseams. To sum up; it is considered that during the coal-forming period or periods —there may have been as many as three- shallow, estuarine basins became choked with vegetable material, in part growing in place forming marshes and in part rafted in by the currents of sluggish streams. Frequently the sea inun- dated the otherwise freshwater marshes, carrying in the clay and sand now represented by shale and sandstone partings. The conditions as outlined above are believed to be appli- ^Ibid. pp. 68 ttMtq. 154 cable in general to the Cretaceous coals of Graham island . Whether the various seams arc identical, or occur even at nearly the same horizon remains to be considered. In the Honna basin, there were probably two coal-forming periods, during the earlier of which coal in the western part of the basin at Cogw itz, Slatechuck, and Yakoun lake was accumu- lated. During this period deeper water conditions seem to have prevailed over the central and eastern portions of the basin, as there appears to be no coal in them. Later, the shoal water extended as far east as the central part of the basin and the seam at Camps Robertson and Anthracite was formetl. This seam does not appear to extend east or south as already men- tioned. From the different character of the sediments of the Yakoun basin, including both the enclosing rocks and the coal itself, it appears probable that the Wilson seam is distinct from the seams in the Honna basin. While the Cretaceous sedimentation was doubtless continuous over what is now south-central Graham island, the pre[)onderancc of evidence seems to favour the theory that the coal seams were accumulated in localized, relatively small basins, and that it is vain to search for the Wilson seam in the Honna basin or the Honna Basin seams in the Yakoun basin. It is not planned in the present report to consider the pro- Cfiws that have acted to form the bituminous coal of Camps Rol)ertson and Wilson. A consideration of them may be found in various papers on the origin of coal, and no new facts bearing on this stage of '.oal formation have been noted on Graham island. Certain observations and deductions, however, with regard to the formation of carbonite or natural coke and of the anthracitic < oal of Slatechuck valley and Cowgitz, will be set forth here. Other facts on which the theory is based in part have bc'jn already stated. The apfKarance of the anthracitic material of the Slate- chuck valley, ( owgit/, and other places, together with its ana- lyses and m(xle of occurrence have been already described. It is to be emjjhasized that this is a true bedded, syngenetic deposit, a coal seam to all intents and purpf^sfs, and differing from an- 155 thrarite essentially only in being unable to support combuNtion under ordinary (onditions. Intersecting the shales in which the coal is found are several dykes and sills of the Ktheline volcanics, like those shown in Figures H anfl on pages 71 and 72. The metamorphosing action of these igneous rocks, through the application of lieat. is believt?d to have deprivi^l the coal of its volatile constituents, and, to have left it in its present condition. That molten igneous rocks intersecting coal seams exert a strong devolatili/ing action on the coal is well known,' and also that this action is eflective only l(Kally.- Tiiis localization of the metamorphosing effect w ill explain why only a part of the Cretaceous coals on draham island are anthracilic. In the anthracitic district of (iraham isl.md, the intrusive bodies have been shown to be particularly ai)undant and -umc are of considerable size (the 5()-foot dyke near \nchor cove lur instance); and the intrusives in general have been accompanied by considerable volumes of heated waters. It is thought that these heate.(ii'ti. than through the baking of the coal by conductioi.. The latter process is very slow,^ while any contact nietamorphic deposit gives evidence of the efficiency of heat transfer by heated waters.* In place of the above theory, that contact metamorphism was the effective agent, the regional metamorphism hypothesis deserves consideration. This hypothesis in brief considers the degree of anthracitization to be propd. p. 3H. 157 "At Skonun point at low tide there are exposed more than ten seams, of varying persistency, of a tough woody lignite, which is curiously more resistant to wave erosion than the sandy shales with which it occurs. The seams range from 1 to 15 feet in thickness. The lignite-bearing measures have been consider- ably deformed, the structure apparently being a small anticline with a general cast-west strike, broken along the crest by a nearly due east strike fault. The southern limb of the anticline con- tains the lignite seams, which dip inland at angles varying from 25 to 60 degrees. An inclined bore-hf.Ie has been put down to a depth of 1,000 feet in the propeity, which is controlled by the American-Canadian Coal Company. It is reported that thir- teen seams of lignite of more than a foot in thickness were struck in this distance. Near the surface, the lignite is of the same woody nature as that exposed in the beach, but it is said that the lignite found in depth is of a more coaly nature." The character of the lignite exposed at the surface is shown by the following proximate and ultimate analysis of a thoroughly air-dried sample collected by the writer from the thickest seam. The proximate analysis was made by F. G. Wait in the laboratory of the Mines Brunch, Department of Mines, and the ultimate analysis was made by E. Stansfield in the fuel testing laboratory of the iJ^-ji^rtment of Mines. Proxiinaf<> analysis: — ^'«e'' 11-03 \'ol combustible 49-75 Fixed carLK>n 35-94 ^h 3-28 *^<^ 39-22 I'-< character — colwren' but tender. ^ J*! ratio {} 72 Spit' -/.jlatile rafio 2-33 -'kimatt- i»*i»Iysis: — '^'■"■''O'' 56-3 Hydrogen . 5.9 '^''^'•ogen 0.3 ^^i^yjfn 33-1 Snil»i*^^r q . j IWoisf u