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TH4^aT3H 
 
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 KINOSTON. ONTARIO 
 
 I 
 
(Kfpntiled froo- Econhmic Geouioy, Vol. XIV., No 4, Jun«, 1919 ] 
 
 NOTES ON TIIK I'LACER MINKS OF CARIBOO. 
 liRITISH COLUMBIA. 
 
 J. U. TVKKI.U.. 
 
 In a brief trip made to tlie placer mines of the Cariboo district. 
 British Columbia, in the summer of 1918, .M,me data were gath- 
 ered pertaining to the distribution and geolojjical features of the 
 auriferous gravels, particularly in regard to the existence of ex- 
 tensive beds of pre-glacial gravcLs below Cilacial deposits, and the 
 greater influence of stream piracy over glaciation in changing 
 the courses of streams. They are here presented in the form of 
 brief notes. 
 
 It is not my intention to describe the configuration of the coun- 
 try, the details of its geolog\-, or the extent to which it is being 
 mined. The Geological Survey of Canada began a survey of 
 the area last summer, and intends to continue it until it is able to 
 publish a complete report with detailed maps of the geolog)' and 
 structure of the country, not only of the older rocks which under- 
 lie it, but also of the later formations and of the influences to 
 which it hns been subjected to form its mountains and valleys, 
 and to deposit the gold in the bottoms of these valleys. 
 
 Mr. Bowman, of the Geological Survey of Canada, made an 
 examination of the countrj- some years ago and published a num- 
 ber of gO(xi maps of the whole district, and of several of the 
 gold-bearing creeks. With these he published a report on the 
 older rocks underlying the country. Possibly the material per- 
 taining to the gravels collected by Mr. Bowman may he incor- 
 porated in the report which is now to be published by the Geo- 
 logical Survey. 
 
 HISTORIC.\L DEVELOPMEXT. 
 
 For many years the country was surrounded with a halo of 
 glory and mystery. Discovered in the winter of 1860-61 by 
 prospectors travelling overland through the rugged mountains to 
 
 \ 2AHr>i) 
 
.rv> 
 
 }. U. IVKHIU.L. 
 
 ilu- -until. ..^^.r nl,:.l, u ua^ .ilni.-.t inii.,sMl,le to tran>|..>rt Mip- 
 |'!ii>. .-111,1 . It uliicl, ihe lianly tr iiticTMiien were .,Wij,a.,l t , .U- 
 
 '"■'"' ''•"■ ' ' "" ''"■• '•.->r!l..'M that fanifd ilir..ii^'Ii the f..rc-i>. 
 
 it ua, hi.lce.l a .liffinilt c..nn'ry !■• read., hut alter it was readied 
 the leuanN f. ilie iM..,urr, uta- ;;rcat. Writin-; in the autiniin 
 Mt i.Vf.i (.Mvcrnor |;n„.ln, -ay, tliai he ha,l met a lar-c niitiiher 
 ■'t men wh.. ha.l reinriie.I frMin the new -.M camp, .-md withmit 
 eNceptt.n tliey lia.l all I.t-ni Miae-stul. a statement whidi cannot 
 he made lor m.-iny camp*. 
 
 Alter j;nl,l h;id heen ,lisc.,\ ere.l at the Canon on Williams 
 J reck hy Wdh.nu Hict. , Dutd, Ihlh word was quicklv pas-ed 
 hack to the prospector, >cattered alonj; the I-raser River and 
 iliey >onn ma.le llieir way to the new I'.ldora.Io. I„ ,x,,.. and 
 i-^'-.? many parties came in fr..m the s,.nth and also across the 
 plains and m-.,m,ain, fr..,, the east until a few years later Kar- 
 kervdle. the center of the new district, was second unlv to \ic- 
 t'Tia in i...p„lation i„ ^-liat is now the I'r nince of Itr'itish Co- 
 liimhi;i. 
 
 Since i8.:,S up to the end .,f n,,; the Government Rep,rts 
 sh.ny that Hritish Colu,nh,a produced alxnit $7S.fJOo.ooo wurth 
 ot placer -old. ( )t this amount the Carilx.., coinitry. net includ- 
 ing the Qtiesnd district, pro.juced s'W to the value of $41- 
 = <xj.O(xi. I have not at hand the <letails of the various creeks 
 Inir prohal.ly of this total. Williams Creek mav have pro- 
 di.ce.l ahout S_-3.ooo.cx5o and I.ifjhtninR Creek $;.ooo.ooo. Mr 
 Muller intorme.i me that Williams Creek above 'the Ca.-.nn pro- 
 <iuced about St. 000 to the running foot and below the Canon for 
 a couple ot mde^. abom s^-,00 to the rnnnin- foot. .Most of this 
 was pr,,duced from shallow ground, where the whole material 
 trom the surtace downwards to the bottom of the paystreak was 
 shovelled into sluice boxes, in which the lighter sand and travel 
 were carried away by the water, while the heavier gold was left 
 i-^ the rittles. 
 
 In the bottoms of some parts of ,he valleys the alluvial de- 
 posits were too deep •„ l,e handled in this way, and there =hafts 
 were sunk to l,ed r. ck. and drifts were run on or in bedrock 
 
/■L.tiLk MIM-.S Of CIKIIWO. UhlllMI CUIAMULI. y^j 
 
 tlin-iif;!! winch tlie rali gukl kariiiK layers was extracted and 
 wa^lieil in sluice Ijoxes. 
 
 Unlike the coii,liti..nN in the mines of the Kl.nidikc the gravels 
 here were not iK-rennially frozen, and con>ei|iiciitIy w.,ter wa> 
 usually present in great nuantity. ihe unwaleruig of the deei)er 
 mine> was therefore a serious and exijcnsive pn.ljleMi and with 
 greater increase in the dei.th of the ovcrhurden, water tinally 
 rendered the deep ground unworkable. 1 could not learn of any 
 individual instance where miners were actually driven out of rich 
 pay gravel which they were mining, hy water, hut exploration 
 and development of deep ground have undoubtedly Ix-en stopjK-d 
 by water, even where rich prosiiects were obtaineti. The ques- 
 ti..n therefore at once arises, how nnich valuable gold-bearmg 
 ground is there still in the <listrict awaiting cheaiK-r transporta- 
 tion, an(l larger and more energetic mining method,. 
 
 TOPOGR.XPHY. 
 
 On the east is a high rugged range of mountains rising in 
 jag-cd peaks to heights of about 7.000 feet. This range limits 
 the known gold-bearing area in that directi.m. West of it are 
 more detached moimtain masses, rising in s.-me jx-aks like Mount 
 Agnes or Bald .^rounta;n. to heights of 6.-00 feet, while farther 
 west the country declines in a series of high transverse ridges 
 seiKirated by deep valleys towards the main \aliev of the I'raser 
 River. The tops of the higher mountains above the elevation of 
 about 5.000 feet are open mo.^rlan.l on which the snow lies imtil 
 well on in the summer, l)iit below this level the slopes are thickly 
 wooderl with fine forests of spruce and balsam, many of the 
 trees in which, in the vicinity of Stanley, would average 18 to 
 20 inches in diameter, while some are as nuich as 31 inches. For- 
 tunately forest f^res do not appear to have swept over the^e 
 mountain sides to the same extent as they have swept over many 
 of the forested areas in eastern Canada. 
 
 coNmrioNs .and development of dr.mx.xc.e. 
 The underlying rocks are mostly schists and slates which have 
 been called by Bowman the Carilx^o Schists, and the prospectors 
 
,v^« 
 
 J It. TYHKELl.. 
 
 from OntnriM \v..nl,| 1„. .truck with the resemblance of the^^e 
 M-hiMs tu the Keewatiii Schists of the northern portion of their 
 own I'rovincc, or niinerN from the Klondike mipht consider 
 them the Klonchke Schists whidi Mr. McConnell has so well de- 
 scrilH-d in "The Klondike r„,ld lidds." Many quartz veins 
 have heen found rnnninf,' throtinh these schists holding gold in 
 appreciable quantities, Init as yet none have appeared to deserve 
 serious development under the difficult conditions of transporta- 
 tion still prevailing in that country. These schists are doubtless 
 of I 're-Cambrian or early i'alcozoic age. and the mountains of 
 
 FlC. 22. 
 
 which they are composed may have been formed during several 
 succeeding periods of uplift and disturbance, the last of which 
 may possibly have occurred since Oligocene times. In this case 
 an additional point of touch with the mountains of the Klondike 
 would ht indicated, as these latter include in their folds beds of 
 Miocene or Oligocene age. 
 
 Subsequent to the final period of mountain building a long 
 epoch of erosion set in. duiing which valleys were developed 
 
fI..ICLH MIMiS or C.lklBOO. UHITIMi i Ol.l Mlil.l. XV) 
 
 radiating; from the iin|).iriaiu iiioiiniam tna-isc- in all direclioii*. 
 Of these iiiDuntams, Mnum Aj^iies or Hald Moninaiii. is tlic in-.-t 
 conspicuous. I-rf)in it Little Swift River iLvv-. (.. tiic smuh, 
 Grouse and Antler frcek-i V) the east. Williams and Jack-of- 
 Clubs Creeks to the iiMrth, and I.ijjIitninK Creek to the west. It 
 is impossible not to recognize the marked resemblance of this 
 central point to the Dome at the iicad of Bonanza Creek in the 
 Klondike. It is true that Mount A^ncs is j.ckkj feet hi>,'her 
 above the sea than the Dome, but the Ixttoms of the .surroundmg 
 valleys are also ahnil 2,0(X} feet higher than the valleys that 
 radiate from the Dome and as hnh sets of valleys are of alMiut 
 the same deiuh. with shijiing wooded sides, the general sim- 
 ilarity of the natural features of the two districts is (juite striking. 
 
 Williams (.V.cA-.— While the valleys were k-ing formed the 
 streams did not always follmv their present water c^tur-es. l-"or 
 instance, the valley of Conchlir Gulch which comes fnun the 
 southeast, crosses Williams Creek, and is c<intinued as Stout 
 Gulch and Lowhee Creek until it oiK-ns into Slough Creek as a 
 hanging valley. Iktween what is now Conchlin Gulcl and Stout 
 Gulch the present drainage is cros-ed and intersected by Williams 
 Creek, the lower fwrtion of which is therefore of later age. 
 though the upjwr ix)rtion was probably originally a tributary of 
 Conchlin Creek. Cons«iuently the old wash of this old Conch- 
 lin-Stout-Lowhee Gulch is of a greater age than the gravel in 
 the bottom of the lower part of Williams Creek, and the stream 
 which once tlowed in it was older than the latter creek. The 
 drainage down Conchlin-Stout-Lowhee Creek must have \kt- 
 sisted for a coiuparatively long time, as the old valley is wide 
 and mature, though the present creeks have cut narrow gorges 
 in the bottom of its floor. 
 
 The main valley of Williams Creek at that time e.Ktended up 
 \'alley Creek, and down Willow River. Then one of its tribu- 
 taries from the south, which extended up pa.«t the present site of 
 Barkerville. cut into the side of Conchlin-Stout-Lowhee Creek, 
 and robbed it of its water, drawing the gold-l:)earing gravel with 
 it down into that portion of Williatns Creek below the Canon. 
 
 I 
 
34' > 
 
 ]. K. TYKkELI.. 
 
 IVniii tliat lime ..nunrds 0>ncliliii Creek discharged into this 
 newer i.nrt of \\illianis Creek, and Stoin Creek developed a 
 -nri,re ( I'late X., o) in tiie upper part of the ahamlnned Stuut- 
 l.-uliee \alley in wliich it tluucd eastward into \\illiam< Creek. 
 instead <<\ nMrihwe-tward ;i, liefMre. 
 
 Hut stream piracy did n.)t end in the rohbinj^ of the water of 
 G,nchlin-Si..m-I.ouIiee Creek by Williams Creek. Slough 
 (.reek I .r >..nie reason (leei)ened its cliannel and fMrmed a gre'rit 
 ui.le valley ( Plate X.. b !. the ll.Mjr of which was about a third of 
 a mile acmx. It must have cut back and robbed the water from 
 the \\illiain<-\\illuw river, f-r Jack-nf-Clul)s lake, which lies in 
 its valley, is reported to be J(X) feet deep, and the bedrock in its 
 valley a little farther we>t was found by drilling to be -'S- feet 
 below the surface, while the louest part of the bedrock in tlie 
 ^alley of WUInw Kiver wa< only 102 feet below the surface. 
 which was probably a little higher than the surface at the drill 
 iK.Ie near .^longh Creek. Thus the original be.lr.,ck bott..m of the 
 valley of Slough Creek is nearly joo feet deeper than that of 
 Uillow River, anrl cnnH-.|uently it undoubtedly robbed the water 
 from the latter stream. 
 
 In excavating its great valley the old Slough Creek, which 
 had donl>tless become a large and important river through the 
 adilition f.f Williams Creek, and probably also of \'alley and 
 Downie-l'ass Creeks, cut away the lower portion of the almost 
 abandoned valley of Lowhee Creek, and of the wide valley of 
 Jack-of-Clubs Creek, reducing them to hanging valleys on the 
 side of the master valley. The original courses of the lower 
 parts of the streams that occupied these two old hanging valleys 
 was not apparent, but it is possible that they turned westward 
 and then somhwestward in what is now the valley of Chisholm 
 Creek, and thus flowed into Lightning Creek, for the upper por- 
 tion of Chisholm Creek valley was also cut away by Slough 
 Creek. 
 
 Luihtning C/rr/.'.— Lightning Creek valley is narrow and 
 \ -shaped as far down as Stanley, the narrow channel in its rock 
 door being often not more than 20 or 30 feet in width. At Stan- 
 
Plate X, 
 
 Economic Geologv. Vol. X(V. 
 
 i 
 
 ./. M..ii!li ,,f St.iif- (.iiVli irMMi \\illi.,in ( mk ~h,.«iim miliim, ir,,m 
 livdraiilu- ..mrali..ti- ii; tiii' I.Ti i;r. iiiii.l. aii.l ^.Ty. in ihv IimiImiti ,.t tin- ..lil 
 inanin \all<> ir, tin li.uk iiiitir 
 
 /'. Wi.k- \^]\^ .,i <.\..nuh ( r, < k I..,.kin,i; n. .nliu<-M«;;i d n,,m M. .-,,11111,, ( r. 
 
 J 
 
 llitf ,,f li,,;ilcl<T i.l;i\ ir,,m l,<.,lr..ck t,, Minaic .iii St.)ut'~ (■ulili 
 
I'L.hliK MIXES or CARIBOO. BRITISH COUMBI.I. 341 
 
 ley the wide U-shai>e(I .lley of Chishnlni Creek joins it from 
 the ncrth. and thence downward^ ilie wh.de valley is wider than 
 l)efnre, and maintains a L'-shapcd character. At a place known 
 a- the P.eavcr I'as^ the main \alley s\\ in;,'^ off to the north, and 
 (I'liibtless the drainai,'e ran fcir a Innj; time in that direction, but 
 the present stream turns s, luhwe.-tward into a narrow S'^rpe be- 
 tween p'cky walls, and continues in it past \\':nf,'<lani towards 
 its junction with Sv.ift River to f.imi Ct^tonwood River. Close 
 to Heaver I'a>s I'eters Creek fVnvs int > Li.L;litninf,r River from 
 the south, and whether the narrow valley of Lightning,' Creek 
 below the continence of these two streams was once the con- 
 tinuation of it^ valley, or was the valley of a tributary in which 
 the drainage has been reversed, is uncertain, though the latter 
 -upi)osition is probably the correct one. I was not able to learn 
 the dei)ih of bedrock bcl'>w the >urf:ice ;it Heaver Pas<, but it is 
 pnibably several hundred feet, fur according to information re- 
 ceived froin Mr. M. liaik-y. the depth from the surface to bed- 
 rock alxiut four miles farther up Lightning Creek is 205 feet, 
 and while the grade of the surface between tlie two places is 
 \ery light, tlie grade of the bedrock is probably much steeper. 
 
 This will indicate the conditions of drainage, and the char- 
 acters of the valleys that had been formed l)y it at the end of the 
 Pliocene Period, and it will be seen that in pre-Glacial times 
 wide mature valleys had been ff>rmed, but streant piracy had 
 been taking place and the streams thaf formed these valleys were 
 robbed by other streams that flowed in deeper valleys. 
 
 Accnmulation of Gold. — During this time gold was being con- 
 centrated into the bottoms of some of these vallevs in larger or 
 smaller quantities, according to the alnmdance of th supjjly. the 
 excellence of the bedrock for forming riffier. or tin. length of 
 time through which the concentration was operative. If similar 
 conditions had continued down to the present there would have 
 been several wide valley . in the district with lieds of gravel cov- 
 ering their bottom lands, through which paystreaks would run. 
 Deep narrow \'-shai)ed valleys and gidches would discharge into 
 them, sometimes from hanging valleys, while in eml)avments 
 
342 
 
 J. II. TYKHELL. 
 
 alMiif; tlifir si(le> wduld i)rMl)aI)ly (.cciir gravel-covered erosion 
 terraces. 
 
 Tlie continuity of conilitions of erosion was suddenly broken 
 by tlie advent of the Glacial Period. There was no general Cor- 
 dillcran glacier in this district with a motion southeastward or 
 northwestward parallel to the trend of the mountains, but the 
 Country was heavily glaciated by local glaciers that flowed down 
 from the mountains into the great valleys. On the side of the 
 mountain nTth of the valley of Lightning Creek near Stanley, 
 and 1,000 feet above the stream, a quartz ledge was seen to lie 
 scored by glacial markings trending northwestward parallel to 
 the course of the vallev.' 
 
 After existing for a long time, and in some cases extending 
 far out over the plateau, even to the banks of the Fraser River 
 itself, the local glaciers retired and disappeared, leaving behind 
 them extensive sheets and deposits of boulder-clay, and large 
 moraines : the latter dammed many valleys and diverted streams 
 into other channels, thus adding to the intricacies of a drainage 
 system which was already quite complicated in pre-Glacial tiines. 
 
 Most, if not all of the valleys had beds of pre-Glacial gravel 
 of varying thickness co\ ering their rocky floors. As the glaciers 
 moved down the valleys they in many cases rode over this gravel 
 and left it, with its cargo of gold, comparatively undisturbed, 
 and at the same time they brought down a certain quantity of 
 material from the hills on each side and formed ground moraines 
 of hard massive impervious boulder-clay, which, on the retire- 
 ment of the glaciers remained as watertight covers of varying 
 thicknr-s over the underhing gravel. Existing streams usually 
 flow on the top of this bed of boulder-clay. In some narrower 
 and swifter places in the upper reaches of valleys they have 
 doubtless cut through it to the underlying gravel or bedrock, 
 and many of the earlier mining operations were probably carried 
 on in places where this had occurred. In these places all the 
 gravel down to bedrock, as well as the upper part of bedrock 
 
 1 " Was tlur-> a Cordilleran Glacier in P.ritisli Columbia." by J. B. Tyrrell, 
 Jour, (if Cii-o!.. \'ol. J-. No. I. 1019. pp. 55-60. 
 
I 
 
 «» 
 
 PLACER MIXES or CARIBOO. BRITISH COLUMBIA. 343 
 
 itself, was shovelled into the sliiice-lx)xes. and washed to re- 
 cover the gold. 
 
 In those parts of the bottoms of valleys where boulder-clay 
 was st.ll lying undisturbed on the gravel the miners sank shafts 
 through the boulder-clay and gravels to bedrock, drove tunnels 
 on or in bedrock, pumped the water from them with Cornish 
 pumps, and extracted the gold-bearing gravel from the shafts. 
 As the gravel was usually porous, the How of water was often 
 large and r'-flficult to handle with the pumps. In fact, in long 
 stretches oi s. ,eral of the valleys, where the pre-G'.acial gravels 
 have been bu.ied to a great depth it has been found impossible 
 to mme. or even to explore them on account of the heavy flow 
 and heavy pressure of water encountered. Further attempts 
 will doubtless be made to explore these deep gravels, but if such 
 enterprises should be undertaken there should be made careful 
 physiographic surveys of the district in order to determine the 
 particular valleys or parts of valleys into which most gold was 
 discharged, and the localities in which it probably lodged. 
 
 An interesting feature was observed on some of the gulches 
 tributary to the larger valleys, as for instance on those of Mos- 
 quito and Last^-hance Creeks. Both these streams flow in chan- 
 nels bounded by rock on their western or down-stream sides, and 
 boulder-clay on their eastern or upstream sides. In searching 
 for a paystreak in each case the old miners found that the pre- 
 Glacial channel was buried beneath the boulder-clay on the east- 
 ern side of. and at considerably lower level than, the present 
 stream for the glaciers, as they descended the main valleys, had 
 filled the upper sides of the gulches with boulder-clay, and when 
 drainage was re-established in post-Glacial times, the new chan- 
 nels were formed above and to the west of the old ones 
 
 At the Caiion on Williams Creek, where two narrow gorges 
 have been cut on opposite sides of a rocky knoll, the direction of 
 movement of the glacier would appear to have been more or 
 less transverse to the course of the stream at this point, and the 
 glacier completely filled and covered up the eastern of the two 
 gorges with boulder clay, so that it was not until some little time 
 
344 
 
 /. /(. TVHkELL. 
 
 afiLT niiniii},^ was be^iin on tlie ircck tliat tliis ^'Tge \\a> f.iunJ 
 and iiiRii\L'rc(l. 
 
 The valley* so far referred to lia\e had beds of pre-Glacial 
 gravel remaining in them, Init two valleys, or ]><)s>il)ly parts of 
 one valley, which came under my notice, namely, Stout-Lowhee 
 and Chisliolm Creek valleys, were different from the rest in this 
 particular, for either mo>t of ihe gravels which had originally 
 covered their lloors had been remo\ed Ijefore the advent of the 
 glacier, or possibly the glacier it>ell may have displaced what re- 
 mained of the gravel, and may have kneaded it up with material 
 brought from elsewhere to form the Iwulder-clay which is now 
 either resting directly on Ijedrock, or is separated from it by a 
 thin layer of poorly aborted material ( IM.ite X., o This ab- 
 sence of gravel beiueen the lx)ul(ler clay and the underlying rock 
 is well shown in a 1 mg luiiiiel into the we-tcrn siile tif the \ alley 
 of C'hisholm Creek. .\lso the hydraulic o[)erations which were 
 being carried on in -Stout Gulch at the titne of my visit exposed 
 an excclleiu sectii'U of boulder clay, which seeme<l to be fairly 
 homogeneou> from top to bottom. Some of it was slightly aurif- 
 erous. On A'osquito (iulch, where hxdraulic operations were 
 also being conducted, and where boulder-clay along with botli 
 overl\ing and underlying gravel was being broken down ami 
 washed through sluice ixixes, some of it was decidedly auriferous. 
 
 In addition to forming a blanket over the earlier gold-bearing 
 gravels the boulder-clay would a[)jiear to have l)een deix)sited in 
 some places of sufficient thickness to divert streams into new 
 channels, as for instance at Beaver Pass House, Lightning Creek 
 has l>een diverted to a narrow western froin a »»'ide northern 
 channel, probably on account of the deposition of a thick l)ed of 
 boulder-clay in the latter. 
 
 In addition lo the deposition of a Ijed of boulder-clay over 
 most of the surface of the lower land the glacier formed terminal 
 moraines across the b(. toms of the valleys. One of the most 
 conspicuous of these is in Slough Creek valley, and extends from 
 the west end of Jack-of-Clubs lake for several miles westward to 
 a point some little distance Ijehnv the mouth of Devils' Creek. 
 
J 
 
 I'L.ICER MIXES or C.IKIBOO. IIRITISH COLUMBIA. 345 
 
 This niuntine blocks the drainage of tlie valley, ami forces the 
 water issuiiifj from Jack-of-Chihs lake to How down the valley 
 of Willow River. 
 
 Another hilly and sti>iiy moraine lies in the b-Jttom of the 
 valley of Lightning Creek between the mouths of Chishohn and 
 Davis Creeks, but it had no intluence on the general drainage 
 except temporarily to dam back the water into a small lake. 
 
 Altogether the diversion of drainage from one valley to an- 
 other would seem to have been affected much more by stream 
 piracy in pre-Glacial times than by moraines or other dams in 
 Glacial or post-Glacial times.