GBOLOCHOAL AND NATURAL HISTORY SURVEY OP CANADA. 
 ALFRW) R. C. SELWVN, LL.D., F.li.S., F.G.S., Dikectob. 
 
 REPORT 
 
 OF 
 
 aEOLOaiCAL OBSERVATIONS 
 
 IN THB 
 
 SAGUENAY KEGION. 
 
 BY 
 
 ABBE J. C. K. LA FLA MM H, A.M., D.I)., 
 
 lliOII»HOR OF MINBRALtKiY AND (HOOLOCi , I WAI. UNIVHRSin 
 
 rUBLISilED BY AUTIIOlilTY OF PAIiLlAMENT. 
 
 MONTREAL. 
 DAWSON BROTHERS. 
 
 1884. 
 
 ' * • 
 
 • k I 
 
• • • . 
 
To A. R C. Selwyn, LL.D., F.RS., F.G.S., &c. 
 
 Director GeologiccU and Natural History Survey of Canada. 
 
 Sib, — In your instructions respecting the geological researchcH to 
 be made in tlie region of the Sagucnay, you wished mo to pay particu- 
 lar attention to the limestones of the Cambro-Silurian, to the bands of 
 crystalline limestone of the Laurentian, to the deposits of tiUtnic iron 
 ore, and in general to all important geological facts which I might be 
 able to observe. I believe that I am in a position to submit to you 
 some now observations on various points, which will to some extent 
 modify the geological map of the Sagucnay region as published by Sir 
 William Logan in 1803. 
 
 Those observations are, perhaps, not as precise nor as detailed as 
 they might have been had I had more time at my disposal. More- 
 over, the difficulties which attend such rosoai-ches in thick forests 
 where the measures are not only covered with dead and live vegetation 
 but also in the majority of instances hidden beneath considerable 
 masses of glacial detritus, must nccessuriiy take away from the clear- 
 ness and precision of a work of observation. 
 
 I have the honour to bo, 
 
 Sir, 
 
 Your obedient servant, 
 
 Abb^ J. C. K. LAFLAMME. 
 Quebec, December, 1883. 
 
REPORT 
 
 or 
 
 GEOLOGICAL OBSERVATIONS 
 
 m 
 
 THE SAGUENAY REGION 
 
 Physiograpuical Sketch. 
 
 The region wliieh I have more particuhirly 8tU(lio<l is that situated 
 to the north-east of tlie Suguenay, from Chicoutimi to Lake St. John. 
 Then I examined in detail the level country lying east of the lake, 
 bounded on the north by tijo small outlet (petite Dicharge), and on the 
 south by the granitic hills which lie near the centre of Labarre Town- 
 ship, then by the elevated land which runs uninterruptedly and in a 
 straight line from the west end of Lake Kdnogami to Lake St. John 
 where the Metabetchouan River empties into the lake. 
 
 The portion situated to the nortli-east of the Saguenay is, to a great 
 extent, limited in that direction, and to the south-west, by two small 
 slightly elevated chains of Laurentian hilla, distant at various points 
 from four to five leagues. This kind of basin-like area widens 
 out, however, going up the Dechanje until it merges in the vast 
 swamps which reach Lake Tshistagama and river P^ribonka. This Hat 
 countiy is everywhere covered with a thick layer of quaternary 
 deposits. Taken as a whole, it is eminently suited for agricultural 
 purposes. Besides, as numerous rivers traverse it and flow into the 
 Saguenay, it is one of those districts where lumbering is carried out 
 on a large scale. 
 
<» D QiKnKr. 
 
 Tlio similar plain which lioH to the onslwiird of tlio lake is ulrontly 
 Hottlod iind culfiviited to u JJir^c cxICMt. Tho general Hiirfacc would l»o 
 quite level wmo it not for thoHt- tortuous and deep ravines which 
 the rivore as woll as tho small hrooks have worn out in all diroctictnn. 
 A few outcrops of Luun-ntian rocks are also seen therein, outcrops 
 which moreover, are always marked l»y slight clevati<ms. This level 
 tra(rt resembles closely that occupied hy thc^ townships of (Miicoutimi, 
 Hagot and LaterriOre, wliero the generally level surface is again only 
 broken hy the ravines made by the flowing waters, and its borders are 
 occupied by ranges of Laurentian hills. 
 
 Laurentian. — A. 
 
 The Laurentian in the area explored may be divided into two very 
 distinct series. First, the hornblendic and micaceous gneisses, tho 
 gi-anites, and the syenites, which are seen at Ohicoutimi and Sto. 
 Anno, along Lake Kenogami and on a portion of the shores o( Lake St. 
 John; and second, those extensive labradoritic masses which lie along 
 the Dcchanje and on the eastern shore of Lake St. .lohn. 
 
 I. Gneissic Series. — (rneisses predominate everywhere, whilst true 
 granites and syenites are comparatively rare. At Sto. Anne, the rocks 
 contain inany hornblendic minerals. They are associated with a largo 
 number of quartzoso and folsj)athic beds or bands which strike generally 
 at right angles to the Saguenay Kivcr. 
 
 These bands probably indicate the original sti-atitication, notwith- 
 standing the fact that in certain cases they ai-e strongly ccmtorted and 
 appear rather like veins or dykes. Yet, they are evidently contempo- 
 raneous with tho associated rocks which hold them. 
 
 These indications of stratification arc well exjtosed over the whole 
 ridge which separates Ste. Anne from the Tvms rompues. 
 
 A few indicaticms of foldings can also be recognized. Moreover, 
 similar beds can bo traced to the mouth of the Saguenay, following 
 essentially the same strike. A little above Shipshaw, tho gneissic 
 series is interrupte<l b}' a large band of labradorite. It reappears fur- 
 ther, but sensibly chtmged as to its nature and appeai'ance. 
 
 The felspar predominates, ai\d the rocks, being more readii}' disinte- 
 grated, arc more deci)ly attacked by the atmosphere. At la Dalle 
 the rocky beds which foi-m the shore of the Kivi6re ties Aulnets, are 
 rich in common garnets. 
 
 About live miles above the mouth of the Riviere des Aulnets on tho 
 Saguenay, the gneiss <lisappears completely and is re|»laced by nearly 
 j>ure labradorite. 
 
 Unequal decomposition by atraospheri<" action since the glacial period 
 on these Laurentian rocks is very mai-ked ; juany of the rounded and 
 
UFiAMMc] HAOUENAY AND LAKE ST. JOHN. 7 D 
 
 polished Hurfaces havo liocomo quite ruij^od. liuyors of quartz and 
 other rninoraln, rich in silica are iel't in relief, whiJHt thone more 
 easily deconipoccd have hooii removed to j^reater or lessor depths. 
 
 I must point out a very romarkahlo fact with rcj^ard to the erosion 
 \ty the ice. As mi^ht he expected, the northern slopt^sof the rocky hills 
 have been moi'e etl'ectively attacked than the southern. The crests of 
 those which ci'op out from beneath the qiiaternai^ clays are worn and 
 rounded on the northern slopes, whilst the opposite slope is still otlen 
 abrupt and ru^^^ed, indicating that the course of the glacial current 
 was from the north and north-west. 
 
 II. Ldbnulorite series. — It is a difficult matter to locaite jtrecisoly 
 the first appearance of bedsof labradorite alon/^ the Saguenay. Still it is 
 only in the neighborhood of Shipsbaw river that such beds can be said to 
 ac<|uire consiilerable develoj)menl, on the noi-th-eastern border of the 
 Di'cfuirije. They are here intermingled with a certain number of beds 
 of gneiss, such as we I'eAsrred to above, an<l are consequently parallel 
 to them. Hut at the (Jran-sorrd, a little above the Duclos Jiiver, labra- 
 dorite compo.ses almost exclusively the rocks of the hills. 
 
 The colour of this labradorite is very dark brown with a tinge 
 of blue in it. From cxjwsure to the atmosphere, it crumbles into a 
 greyish powdery material, and the rocky hills consequently assume a 
 smoky hue which causes a singular contrast with the non-decomposed 
 portions. 
 
 The rock is compact, with an eminent crystalline fracture and exhi- 
 bits large crystals with faces marked by the characteristic striaj of the 
 plagioclase felspars. 
 
 Jn certain places these labradorite rocks have a cellular structure. 
 This phenomenon arises from tl:e decomposition of small patches of 
 foreign minerals, originally imbedded in the labnulorite and sh)wly 
 disstdved by atmospheric agencies. This decomposition, commencing 
 at the surface of these isolated patches, has extended by degrees to 
 the centre, forming a number of chloritic leaflets, in clusters radi- 
 ating around a central point. This peculiar leaf-like decomposition 
 is due to an original concentric structure, developed by the action 
 of frost and snow on the glacial surtace. It is not rareto meet some 
 roches moutonnces labradoritic in composition, the summit of which 
 is covere<l wiiJi leaflets neatly separated. Their thickness varies 
 from a few lines to a tew inches. This exfoliation is much better 
 marked on the sui-face of the labnvdorite rocks than on any other. 
 These various disintegrating actions were doubtless at work pre- 
 vious to the glacial epoch as well as subsequently, and the labradorite 
 rocks must have been decomposed to a gi-eater depth than the granitic 
 I'ocks at the time when ice invaded the country. Whence it lullowu 
 
H l> QIJKIIEC. 
 
 that thcHi^ rocks Imvo boon moro deeply eroded during the glacial epoch, 
 and this would perhaps explain the fact that the lahradorite hills of the 
 Saguoniiy are, aw a general rule, lower than the granitic! or those of 
 gneisH or sy«'nite. At flrHt wight it seems as if the surface of the 
 country occupied hy tho lahradorite had iindi-rgonc a Uind (»f a dcpres- 
 hioii, whilst in reality this appcai-ance may iiio-e likely he sulely due 
 to great«M' erosion. 
 
 To sum up my ol)serva(ionHon those developments of lahradorite, I 
 Hhall state that these rocks occupy a pretty extensive area on tho 
 eastern shore of tho Saguonay. They hegiji al the Shipshaw IJiver, 
 folhtw tho Auinets as fiir as the sixth or seventh ranges of Hourget, 
 withoii'. reaching lakes Chahot, Tliomy and des Ih'ochets, then are 
 exposed on tho northern shore of Lake 8t. John, from the Dcckarge to 
 to tho liivii^ro an Cochon. 
 
 This formation jji'ohaltly extends further north, perha|)s rea<diing 
 I'onlionka River. However, the extensive swamps hctween the Lac 
 dos Brt)chetw and that river would render ohservations extremely 
 ditHcult. 
 
 The island of Alma itself is composed solely of lahradorite with a 
 few heds of intcrsti-alitiod gneiss. 
 
 To tlie south shore of the outlet, similar lahra<lorite masses ai'o visible 
 east of tho Church of St. Dominique, and again continually on the right 
 hank of the river as far as the lake. Finally they compose almost 
 entirely the hills found hetween St. (iedcon and tho Petite Dccharije. 
 
 Amongst tho most important minerals which this formation hidcls, 
 titanic iron ore may ho mentioned first. 
 
 The lahradorite pehhlos which are found in the noighhorhood of 
 Shipshaw often enclose this mineral, ami it appears to occup}* a posi- 
 tion analogous to that which hornhlcnde occupies in syenite, to such 
 an extent that at lirst sight these i-ocks might he mistaken for ordinary 
 syonitic fragments. 
 
 The mass which I was able to study most thoroughly is found on the 
 first range ofBoiirgot, at a short distance from Tache township. This 
 mass is about two arj)cnts wide and four or five long; but it is found 
 again in different places on the same direction, at a considoral)le 
 distance from tho Saguenay. Tlie mass in Bourget forms a regular 
 hill, 150 feet high, compi)sod almost exclusively of titanic iron. 
 Felspathic veins with strange configuration are, however, Ibund in 
 the same. They remind me, remotely perhaps, of I'rince Rupert's 
 drops with this difference that they are much more iri-egular. Lai'go 
 crystals of lahradorite are likewise often met with. 
 
 At first sight, tho structure of these ferruginous masses is so dis- 
 turbed that an igneous origin is suggested. 
 
lAFUMMt] SAdI ENAY AND LAKK ST. JOHN. f) D 
 
 The action «)f Iho (|imlornaiy glacier was rcinarkahly cxoinpliHt'd 
 in the cano of tlii-sc minerals, lari;c Hiii-facos lK'ir>/^ foiiiid whicli have 
 still proH»>rvc<l the original |M)liMliiiig. OlhcfH have hecoine rugged, 
 ami eolhdar, by tho docoinpowitioii of foreign suhstaniHts oi-iginally 
 mingled with the titanic iron. 
 
 The occurrence of ilmcnite in several placen which Sir W. Logan 
 dooH not inention in the (leology of (Canada, IStJ.'J, has also \)vvu noted. 
 Tluf principal on(*s are : At .lervai.s liivor, on tho hanks of Shipshaw, 
 on tho second range of .Ion([uiero and on tho first range of St. tJtjdeon. 
 
 A word now about tho dilleront veins which tnivorso tho labradorito. 
 At Trdpannicr Bay, on tho island ot' Alma, there is a voi-y remarkable 
 vein of orthoclase prt'tty nearly jtuie and ciystallinc. It runs north 
 north-east lr(jm the bay and has a dip ot about 7**^ Analogous veins, 
 two or three foot in thickness, ai'o mot with in various places on tho 
 islands of the Petite Dichanje. i?ather large dykes are also found 
 com|t{)sed of a kind of compiict dolerito enclosing crystallino masses of 
 hypersthene and ilmcnite. These dykes can be si'on again at tho 
 mouth of the (inuule Dccharge and on the shore in the vicinity of the 
 Petite Di'chanje to tho Houth. T^heir strike is nearly at right angles to 
 that of the felspathic veins referred to above. 
 
 The Laurentian formations which I iiave o.xamined hold several 
 minerals which we will briefly cite here: 
 
 Mica is found aliundantly. It is met with in large laminte, capable of 
 being utilized, at I'Aiise .v Caron, along the Grande Dcrhartje and in tho 
 third range of .loiniuicro. From this lattei* place wo had sheets of a 
 mica, black in colour, about two feet scjuaro. 
 
 Sulphide of antimony was found in a very narrow vein crossirkg tho 
 Saguenay at the height of the liroken lands (Torres Uompucs) dose to a 
 rem!':kable dovelopmont of titanic iron. On the eighth lot of the thii*- 
 teenth rangeof Laterricro occurs a ((Uart/.o-felspalhic vein running from 
 north-west to south-oast, enclosed in gueissoid rock. It contains a very 
 small (quantity of graphite dissominati-d throughout in small masses. 
 
 Another ([uart/.oso vein is Ibuml three miles from the Portage dos 
 Roches on the right bank of the Chictuitiiui Itivcr. Its thickness is 
 from eight to ton feet and diiection noilh to south. It is rich in iron 
 pyrites. Gold was thought to have been present, but the analysis haa 
 shown that tho pyrito was not auriferous. 
 
 In the township of .Ion([uiore, on the north range of the road lead- 
 ing to Kaskouia there is a curious agglomeration of precious minerals, 
 specially garnets and emerald. The gai'nots are rarely transparent, 
 save those surrounded by masses of mica, but then they arc unfor- 
 tunately very small. The emeralds belong to that variety called 
 
10 D QCEBEC. 
 
 «' aqua-mai'inc." Ciystals have been found reaching a diameter of 
 three iiuho.s and moi"e and a length of from twelve tf) tifleen inches. 
 
 The cryrttalline limostoneH which are elsewhere characteriHtic of 
 the Laurentian were not observed an^^where. The only calcare- 
 ous rocks met with are a few narrow veins traversing (he Laurentian 
 hills invarious places. .Such are, amongst others, the veins of Shijishaw, 
 near the (irande Decharge. 
 
 However, I must especially mention a nuich more considerable mass 
 of lime-rock examined on the second lot of the Hrst range of Metahet- 
 cliouan, quite (dose to the so-called (Quebec road. On the side of a liill 
 some one hundred feet in height and running north and south a mass 
 of white limestone coarsely crystalline can be observed which is com- 
 posed of rhombohedral crystals. This limestone rock may beseen more 
 than tifty feet long and about twenty feet thick. It is surr(mr\de<l by 
 gneiss which is also found in all the adjoining hills. Unfortunately the 
 mineral and vegetable detritus which cover the country render the 
 examinatiim extremely difficult, to such an extent that it is almost 
 impossible to define the boundaries of the limestone in a precise man- 
 ner. Whether it is a vein or a remnant of a large mass of crystalline 
 Laurentian limestone could not be affirmed with certainty. 
 
 Cambro-Simirian. — D. 
 
 The examination of the Cambro-silurian formations was one of the 
 principal pai-ts of my programme, accordingly I have paid particular 
 attention to the same. 
 
 In the Geology <»f Canada, ISl?;}, Sir W. Logan menti(ms solely the 
 limestones which occur on the island at the entrance to the Petite 
 Bechanjc and those which border the southern shore of Lake St. John 
 from Metabetchouan to Blue Point. 1 believe that 1 have discovered 
 the boundaries of another lai'ge ('ambro-silurian basin to the north-east 
 of the Saguenay, not reckoning a goodly number of smaller areas, 
 which, although isolated, can however be grouped so as to form minor, 
 but perfectly characterized basins. As the tirst-mentioned and largest is 
 for the most part in Ste. Anne jtai-ish, 1 shall call it the Ste. Anne Basin. 
 
 The strata which compose it ai'c all limestone and referable to the 
 Trenton tiroup. The following is a list of the localities where I have 
 ascertained their occurrence with the loading characteristics whieli they 
 oti'er in these different places ; — 
 
 First, they are found on the thii-d range of Tremblay, about 40 ari)ents 
 from (he Saguenay, and about 270 I'oet above the river. There the}- 
 rest directly on the gneiss, and their thickness is so slight, at least on 
 the bonier of the formation, that the undulations of the gneiss uro 
 
laflamme] SAQUENAY AND LAKE ST. JOHN. 11 D 
 
 brought to light through their edge The ahsohite horizontality of the 
 Trenton beds ])i'eviiilH over the wliole of the Ste. Anne basin. 
 The roail ciosscs this caU-aiTous .series, almost at jight angles to 
 the .strike of the strata, which is south-west. It hero tbrnis a hill 
 about 40 feet high. To the south-west it altuts against Laurentian 
 masses. To the north-east it dijjs below the deposits of ([uatei-naiy 
 clay.s. It lias in that locality a width of about .'5(1 rt/'/je/t^s. The qua- 
 ternary clays which hegin here, form an extensive plain stretching to 
 the limits of the townships of Tremblay ami Simard. The general 
 surface is quite regular, except in those places where brooks 
 and rivers run, whoso beds are always worn deep. The soil is very 
 fertile, and already a fair ])orlion of it is being cultivated. 
 
 Towards the boundaries of the township menticmed abf)ve, the surface 
 rises sensibly, and between Lakes Caribou and Charles another lime- 
 stone band is seen to cro|) out (juitc like (he limestones of the third .angv, 
 of Tremblay. The gneiss hills begin again beyond and "ontinue as far 
 as the Valin Mountains which sejtarate tlio waters of Haguenay from 
 those of the lietsiamits Eiver. This liand of limestone is somewhat 
 thicker than the one already described. It is Jilso longer, for it is 
 found again between Lake Tortu and IJivcr Shipshaw, a very good 
 natural section of it being there exposed. The Shipshaw River itself 
 runs more than a mile upon these limestone beds, the Ours River, which 
 flows aljout a league west of the Shipshaw, does the same. 
 
 On the eastern side, at the bouM<laries of Tremblay township, the 
 Valin River has likewise woi-n its bed in the limestones, and that to a 
 considerable extent. 
 
 From all these observations it can be aflirined that to the north of 
 Tremblay and Simard townships, there exists a great band of Trentcm 
 limestone running almost parallel with the boundaries of those town- 
 ships. 
 
 The limestone band rti-st refei-reil to also extends in a ilircction from 
 east to west, being found again at Kiviere aux Va-^es and Caribou 
 River. In both places the beilsare overlaid by very extensive deposits 
 of clay, but these are cut through by l)oth rivei-s down to the lime- 
 stone. 
 
 A])parcntly the two bands of limestone are only parts of the rim of 
 a large basin, its central portion being covered and concealed by the 
 alluvial ileposits referred to ; ason theeighth range of Simard, between 
 the 11th and 2lst lot, the limestone is only a few feet below the 
 surface over a breadth of about twenty arpents. This is also the 
 case in the sixth range of the same townsiiip, where the soil is liter- 
 ally covered with pebbles of limestone. In this last mentioned locality 
 an abundant sulphurous spiing occurs. 
 
12 D QUEBEC. 
 
 To sum up, I have ascertained the presence of limestone over an 
 area about ten miles broad and soventecn miles long. In the whole of 
 tliis area there is not a single outcrop of the gneissic series. It is an 
 extensive wooded orcidtivated plain. This Cambro-silurian basin is, as 
 stated, limited to the north and south by the limestone bands just des- 
 cribed, but it is not so to the east and west. Time did not allow me to 
 exan\inc (ho eastern bomidary. As to the limits of the basin to the north- 
 west I bolieve it to bo very difticuit to determine, seeing that from the 
 River Ours to r«jribonlca and to Luke Tshistagama, the surface of the 
 country is only a vast plain often covered with swamps and where no 
 rock outcrops have been seen. Tiiis rtimark, however, applies onl;> to 
 that [tortioii which lies beyond tht; surveyeil townships, for the 
 contrary is the case in these hittei-. In fact the Aulnets Eivei', which 
 cros.ses Bourgct township, in no place flows over limestone beds. 
 Lakes Chabot, Thorny, anil des Brochets have gneiss or labradorite 
 shores, the same is the case with the Mistouc River. Tiie lime- 
 stone basin of Ste. Anno is, therefore, clearly limited on that side. 
 
 There is no doubt that tliese limestone formations were originallv 
 more c.\tei\sive, and tiiat they were reduced to their pj'csent dimen- 
 sions by glacial ei'osion, which has left (oo extensive traces on tlie 
 granite hills of the SagucTUiy not to have affected considerably the 
 comparatively soft surfaces of the adjacent jjahcozoic j-ocks. 
 
 The limestone l)eds are cveiywhere crossed by numerous joints 
 behniging to two systems nearly at right angles. The lower 
 beds, those which are in close contact with the granite, are com- 
 pact, dark in colour, with a light tinge of blue. Fossil remains are 
 abundant. They are fjund crowded together, espt'cially in certain 
 lieds. However, it is dillicull to find peifect specimens. They are 
 naughl but friigments accumulated in such a way as to make identifi- 
 cation almost iinjjossible. 
 
 Besides (be l<)ssils, there are seen in the mass of the rock small crys- 
 talline grains, such as are found in the Bird's Bye formation. 
 
 In (he upper beds of the same basin, tlie fossils are more abundant. 
 A few lasers appear to be almost exclusively composed of crinoid 
 stems. Tondjstones obtained fron\ these lieds present specimens of 
 pretty paheozoic aiga\ Let us also adil that these beds are crystalline 
 and resemble pretty closely the limestones of Deschaiiil)ault. 
 
 Petroleum is not rare throughout this whole areaof (Jambro-Silurian 
 rocks. Sometimes it exudes spontaneously from the cavities of the 
 rock, and when the rock is heated it gives forth a very marked 
 bituminous oilour. All the limestones of tlie Haguenay are also bitumi- 
 nous, whi(;h eslablishes clearly their relation to the Trenton group. 
 
iaflammh] SAOtTBNAY AND LAKE ST. JOHN. 13 D 
 
 To complete the study of Ste. Anne basin, it would bo necoHsary to 
 tind out the caistorn and western limits, and also ascertain besides other 
 facts, whether there are not between Valin Mountains and Botsiamits 
 Eiver deposits which belong to the same horizon. The guides certify 
 that rounded j)cbble8 of limestone are found throughout that whole 
 region. 
 
 Lake St. John Basin. — In the Geology of Canada, 1863, Sir AV. Logan 
 states that the limestone formations must probably nearly cover 
 the bottom of Lake St. John, though it is soon only in two places. As 
 regards the boundaries of these two limestone areas, as laid down 
 by Sir William, 1 shall point out* that the first one does not begin at 
 the mouth of the Motabetchouan, but about a mile and a half farthoi- 
 west. The (brtnalion attains almost immediately a thickness of about 
 one hundred feet, always in horizontal beds excejit near the lake, where 
 they dip towards it. It is, moreover, singular that the bods of this 
 whole limestone area, which are near the lake, alwaj's dip towanls it. 
 
 At the point where these limestones first appeal-, black bituminous 
 bods of Utica slate are found i-esting unconformably against the lime- 
 stone ; a phenomenon probably due to a fault. These beds hol<l such a 
 quantity of bitumen as to have caused the iurmers to mistake them 
 for coal, finding that they burnt with a flame. 
 
 At Oniatchouan liiver, tlu^ Utica shales rest confoi-mably on the 
 limestones, being directly superimposed. Hero they are but slightly 
 developed, and disappear beneath huge masses of clay. At Ouiat- 
 cliouaiush liiver the limestones rest immediately upon the granite. 
 Fifteen arpents west of Point Blue, the Utica argilites reappeai-, 
 resting conformably on the limestones. They dip considei-ably towards 
 the lake. 
 
 The Cambro-Silurian band along the north-western shores of Lake St. 
 John is relatively narrow. It scarcely extends beyond the second range 
 of the Metabetcliouan and Chambord and the first range of Roberval. 
 Farther south the granitoid Laurentian hills begin. These limits are 
 only approximate, seeing that I had not an opportunity of studying 
 them in detail. It would be very interesting to ascertain exactly (hat 
 lino of demarcation, also to make sui-e whether the limestone band 
 around Pointe Bleueis continuous over the vast basin whei'e the Ashou- 
 apmouchouan and its various tributaries flow. There is eveiy reason to 
 b(!lieve that another paheozoic basin, equally developed, may bo found 
 there. 
 
 The limestone island referred to by Sir William Logan, which is 
 situated at the mouth of the Petite Decharye is very large. When the 
 water is low its exposed length is from three to four miles and its 
 breadth two. The limestone may even bo traced beneath tho wateis 
 
14 D QUEBEC. 
 
 at a good distance from the island. This island is itself but little 
 olovatod, and when iho water is hi<;li, is completely submerged 
 o.Kcept the tops of the trocw which cover its surface ; the beds, always 
 horizontal, aI)oun<l in fossils: corals, brachiojKxls, gasterop(»ds, ceplialo- 
 pcxls, i*tc. 
 
 Jt is natural to suppose that this limestone island is one of the sources of 
 the pebbles of limestone which are found quite often on the shores of 
 the outlet of Lake St. John, and also in places apparently very i-emote, 
 from limestone formations. In this light I have noticed such pebbles 
 at the Grand Jiemou.x, at Jorvais Kapids and in various places along 
 the Petite Dicharge. 
 
 They are torn up by the i(;e and transported here and there during 
 high waters. 
 
 I have further found limestone beds in many other localities at the 
 eastern extremity of Lake St. John, to such an extent that formerly this 
 formation must have covered the whole of that portion of the country 
 in which are now the parishes of St. Jerome, Ileljcrtville, frrammont 
 and Alma, except pei'haps a few Jjaurcntian islets. It was subsequently 
 removed by successive denuding agencies. Tlie limestone pebbles, how- 
 ever, still lie around to such an extent sometimes as to allow the erection 
 of lime-kilns. Among s\ich ]>laces may be mentioned, the 30th lot of the 
 eighth range of Signay, the 7th anil 8th lots of the tirst range of Alma, 
 different lots situated at a short distance to tlie north-east of Grammont 
 church, and near St. Jerome church, moreover, there are others where 
 the limestones are still in situ.'-'- 
 
 On the Island of Alma, twenty ai-pents to the east ofTrepannicr Bay, 
 there is ai\ outcrojt of limestone resting directly upon the Laurcntian 
 rock. As the exce]»tion, these beds are highly inclined toward the 
 north-cast. 
 
 On the other side of Alma Island on the right bank of the Grande 
 Decliarge we find a similar limestone formation. The same is the case 
 on the 25th lot of the eighth range of Signay, whei-e horizontal lime- 
 stone beds arc, as it were, imbedded in a nest of granite. At that point 
 where the road of the third range of Caron crosses the river Koushpa. 
 ganish, it Hows over limestone beds slightly inclined to the north, and 
 
 •These Trunton limestone outliers are economically important as a source of lime, and they 
 arc nl?o geologically of great interest as indicating the aroii once covered Ijy the Cambro-silurian 
 ocean. The discovery of more such outliers, in the great unexplored Laurentian region between 
 Hudson's Bay and tlie St. Lawrence, may yet prove that the Laurentian Continental nucleus was 
 wholly, or in great part submerged, perhaps more than once in early palicozoic ages. Such 
 repeated oscillations and the great denudation resulting from these may easily have destroyed 
 all traces of formations once sujicrincumbent to the Laurcntian. It is therefore in a modified 
 sense only that the present extent of these palicozoic outliers can be ascribed to glacial erosion 
 which was one of the latest only of the denuding agencies which have taken part in producing 
 the existing physical outlines.— A. R. C, S. 
 
UFLAMME.] SAOITENAY AND LAKE ST. JOHN. 15 D 
 
 covered above with mo)'e than 100 feet of chiy. Fui'thoi- to the west 
 limestones a^ain crop out, on the 7th and 8th lots of the tilth ran,<j;c of 
 Metabetchouan. The dii) is 30° to the north, and their visible thickness 
 about 40 feet. The be^ls are thick and would atl'ord good building-stone. 
 Tlieir extent is from twelve to fifteen arpents in length and tive or six in 
 breadth. Travelling towards Hebertville similar beds present them- 
 selves near Lac ii la Croix, in a small Laurentian depression which i)rc- 
 sorved them from glacial erosion. 
 
 A noteworthy fact is that in all the points of contact which 
 I have been able to observe between the Laurentian and the Tren- 
 ton, tlie latter rests directly upon the former no traces of the 
 Potsdam Cak-iferons or Chazy being seen, ^forcover, whilst the Utica 
 formation is present only in a few instances, still debris from it are found 
 on the shores of the lake and very often inland to such un extent that 
 we are forced to conclude that the whole area of the Trenton was formei'ly 
 covered with this formation. I have pointed out in the course of 
 these remarks the fact that the lime.stoncs are often enough found in 
 nests or outliers amongst the granites. Therefore, these depressions 
 and hills of Laurentian ago must necessarily^ have existed at the bottom 
 of the palasozoic ocean where the limestone beds were being deposited. 
 Consequently, even previous to Cambro-silurian times, erosion had 
 already strongly attacked the gneisses, however hard they were, and 
 to a considerable extent moditieil their surface features. 
 
 There remains to be pointed out another limestone deposit on the 3rd 
 ami 4th lots of the thii-d range of Bagot, near the fourth range. The lime- 
 stone is visible upon a surface of three or four arpents. Elsewhere it is 
 completely covered with the ([uaternary clay. Here again, as through- 
 out the whole Saguenay region, the limestone rests distinctly an<l imme- 
 diately upon the granite. Fossils arc not rare in this limestone, and 
 cavities tilled with petroleum are also found therein. Li the largo 
 plain which includes the parishes of Chicoutimi, trrantl Brill(5, St. 
 Alphonso and St. Alexis, 1 have not found any limestone except Aviicre 
 mentioned above. However, it is quite probable that it should be met 
 with beneath the clay in many localities. In fact, these parishes form 
 a large basin similar tothatofSte. Anne. The Laurentian oulci-ops 
 are few and but slightly elevated. The general surface of the country 
 is level enough except the ravines worn out by the rivers and brooks. 
 Further, but a few years ago, limestone beds were blasted near the spot 
 called " les batiiires," on the right bank of the Saguenay, about on the 
 same level with the limestones of Bagot. It is then not impossible 
 that we have there again another paheozoic basin in which erosion 
 first, and the accumulation or heat)ing up of the detritus of glaciers 
 next, have destroyed or concealed the greater portion of these deposits. 
 
10 I) QKKBEC. 
 
 To recapitulate, I mnst say that hesiilcs the Cambro-Silurian forma- 
 tionH pointed out by Sir William Logan, the region of the vSaguenay 
 eompriscH otherH situated in the Ste. Anneparisii, variouHHmuU outcrops 
 oaHt of Lake 8t. John, and loss extonHivo doposils in frranle Baic ])lain, 
 lo Huch an extent that the palaaozoic ocean must have boon there co- 
 extensive with that of the (j^uaternary age. 
 
 Post-Tbrtiary. — M. 
 
 The PoHt-tertiary doposits of the Sai/nonay are clearly diviNible into 
 two groups just as Dr. Dawson's stmly published in the Geology of 
 (Canada, 1H63, indicates. The lower group comprises the boulder clay, 
 overlaid by a more oi" loss thick deposit of stratified clay. The upper 
 group consists almost exclusively in beds of sand holding at times peb- 
 bles of goodly size eveidy rounded. This sandy group is never verj'^ 
 thick. The brooks and rivers have worn oat their bods in these easily 
 moveable formations into ravines ol' groat ilopth wit.i steep sides. 
 
 The paheozoic basin of Sto, Anno is covered with a thick bod of clay. 
 The sandy deposits arc only mot with in the western portion near Aux 
 Vases Rivei- (Mud Mivor.) It is a curious fact that we frof^uontly 
 tind the sandy surfaces of the teri'acos entirely or in part occupied by 
 swamps. Such is tlie case, amongst others, near tlie Aux Vases Eiver, 
 in the neighborhood of Lake des Brochets and between Chicoutimi 
 and tlio Grand Brftld. 
 
 Little by little the water of the swamj* j)ormeates through the wh<ilc 
 sandy mass and reaches the surface of the clay. It then follows the 
 impermeable surface of the clay in the direction of the greatest slope 
 and comes foi-th in the shape of abundant sj)i'ing8 in the worn out 
 ravines. The springs always come from the line of junction of the 
 sand with the clay. 
 
 At this exit a quite remarkable chemical action takes place at times. 
 The ferruginous material of the clay and sand is decomposed. A 
 more or less abundant formation of yellow oclire results, and is 
 carried away by the spring-waters. The numerous Iwg-plants which 
 grow abundantly in these places undoubtedly have a great deal to do 
 with these chemical actions. 
 
 This formation of limoniie is particularly noticeable in the upper 
 portion of Mistouc River, along the Rivi«^re des Aulnets and also along 
 Bear River. But the most 'Muarkablo place in this respect is at the 
 source of one of the tributaries of the Aux Vases River, where there is 
 a small vale surrounded on three sides by sandy swamps. Water 
 rises in abundant springs, escaping in several small brooks, the union 
 of wliich constitutes one of the principal tributaries of the Aux Vases 
 
LAFLAMME.] SAOTTENAT AND LAKE ST. .JOHN. 17 I> 
 
 River. The ochro foiinod on the brow of the hill is carried away 
 by the water an<i is (le|)C)Hiteil in the lower portion. There is then 
 a deposit of oxide of iron the thicknoMs of which varies from three to 
 twelve feet in an area of more than twelve arp-ents in length and five 
 or six in breadth. The surface portions arc of a rusty yellow colour, 
 but this colour disapi)cars at a ci;rtain tlepth and assumes a greenish- 
 brown hue. This ochro holds but little silica and could be obtained 
 with great facility. 
 
 From the l^'erres Rompues going up the Saguenay, the clay 
 deposits have no longer that iiniibi-m evenness found below. However, 
 they remain stralilied throughout, but have been plougheil and denuded 
 by the waters to such an extent that their jtrimitive surface is 
 entirely gone. T'>ey are only argillaceous or arenaceous lullocks 
 inserted between Tjuurentian hills. At (rervais Uapids the general 
 surface becomes regular and I'emaiiis so to Lakes St. John. How- 
 ever, the immediate neighbourhood of the Dcchunje and Lake Iveno- 
 gami is always more disturbed than the remote districts, which pioves 
 that the waters extended over the count 'y in large volume when the 
 lake basin was narrowing in at the (lose if the Champlain epoch. 
 
 When all the terraces of Lake St. John are examined together, a fact 
 immediately strikes the observer, it is that these terraccw are much 
 more elevated on the south-eastern shore of the lake than in any other 
 place. At Heberville, for instance, they aie nearly 21)0 feet above the 
 level of the lake. From this, as a central point, tlieii" level lowers 
 usually almost imperceptibly as far as St. Prime on one side and Gram- 
 mont on the other. 
 
 This fact appears to me to be capable of interpretation in two ways. 
 It may be that the elevation which marked the close of the 
 glacial inundation was felt to a greater extent in that part of the 
 shore than elsewhere. Or else, the phemtmena of erosion may have 
 been felt more, near the Dccluii'ye and at the opposite extremity, 
 near the Ashuapmouchouan, so as to remove the greater portion of 
 the areno-argillaceous terraces. The former explanation seems to me 
 to be preferable, inasmuch as there is not seen at the surface of the 
 terraces of the Gramniont, the Dechanje and Jtiviere il la Pipe that 
 deep ravine-cutting which ought to have taken jjlace there as they did 
 lowei- dtjwn, along the Dccharge, where the waters have acted power- 
 fully. The noi'th-eastern shore of the lake between the Dccharge and 
 Peribonka should, however, be examint^d-'Ti detail before adopting this 
 conclusion as final. 
 
 The rivers which flow into Lake St. John from the north carry with 
 them a great quantity of sand, produced by the rapid decompo- 
 sition of the hills which boi-der their upper portions. These sands are 
 
 •> 
 
 
18 D QTTEnEO 
 
 fivHt R])rea(l out in t!io lake and fond to fill \i contimially. Thoy ai'o 
 very (lillbi'enl from the (jiiatornury sands |irf»jioi', socin^ Uui( (lu'y 
 contain a considuvahle qnanlity oi Lf.irn«>(s and of mai^nctitc. 
 
 Tho sandy niaHwcs arosLill accinnulafi.'if into narrow riiltjoH upon the 
 8lioro of Coclion llivor aw far as )St. Jeroino. Tho wind wlii(di jilayn 
 the jM'incipal pari in tho formation of (hcso, acts as a siftoi-. The 
 j^arnotH and ma<;nctilo, wliiidi are vory heavy, remain near (he water, 
 wliilst tho liij^htor quartzose i^rains are driven into tho interior, toward 
 the su/nrait of thoso ridgOH oi* dunes. Thewe reaeh a heiifht of 100 feet 
 in some instances. Beyond tliese arid liilis tlie soil is arifiMaceous and 
 fertile, heintf part of the ordinary quateriiary terraces. 
 
 ,1. (". K. I.AKLAM.MK.