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The Lower Triassic Liard River

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The Lower Triassic Liard River CANADA DEPARTMENT OF MINES AND RESOURCES MINES AND GEOLOGY BRANCH GEOLOGICAL. SURVEY PAPER 45-28 THE LOWER TRIASSIC OF LIARD RIVER, BRITISH COLUMBIA (REPORT, THREE FOSSIL PLATES, AND APPENDIX) BY F'. H. MCLEARN Presented to the Geological Survey of Canada by Dr. E. Poitevin 1956 OTTAWA 1945 CANADA DEPARTMENT CF MINES AND RESOURCES MINES AND GEOLOGY BRAWCH GECLOGICAL SURVEY PAPER 45-28 THE LOWER TRL~SSIC OF LIARD RIVER, BRITISH COLUMBIA (Rerort, Three Fossil Plates, a.nd Appendix on New Lower 'rriassic Species, Lia.rd R1 ver) By F.H. McLea.rn OTTA.WA 1945 CONTENTS Introduction ............ ' ..................... l Strati gr aphy e • • • • • • • I • • 1 • • I • • I • • • • t • I • e • • • • I • I • 1 Corr e la tio~ •••••••••••••••••••••••••••••••••••• 3 Notes on fossils •••••e••••••••••••••••••a•••••• 5 References •••••••• • •••••••••••••••••••••••••••• 6 Appendix en new Lower Triassic species, Liard River • ••••••••••••••••••••••••••••••••••••• In envel ope Illustrations Fi gure l~ Index map of fossil l oca lities--Fa cing page l 2 o Correl ation table of Lower Triassic faunas, Facing page l Pl ate I. Claraia cf. stachei fauna, Grayling formation and Wasatchites fauna. , Toad for ma tion (Sheet 1) In envelope II. Wa satchites fauna , Toad forrna.tion (Sheet 2) In envelope III. Wa. satchites f auna , Toad forrnat~on (Sheet 3) In envel ope ,.,,,.-- / ( ~ ) / I / / Cr. .. Foeeil locallthe ....... :•... ... x A LI) o~ Pl•ure 1. lndes map to fo11U localltlee. Scale: I Inch to 4 mlla ' OIVISION!S NEVADA FORT DOUGLAS, UTAH IDAHO CENTRAL CAN. ROCKIES LIARD RIVER, B.C. (Ne we 11 Kumrnel, 1941 (Spath, 1934) (Muller & Ferguson, 1939) (Mathews, 1929) a. (Warren, 1945) (E. Kindle, 1944) Perrin Smith, 1932) o. ,........._ u Prohungaritan ·- -~ Interval ({) If) c <J) U) .2 .~ .µ c .\.. <O of .Q co 0.. .µ ·- I- E - ::J (\.. L I l... Colurnbites 0 Colurn.bit.es CU L (/) erosion E I- -E i)() ::J L s .µ I Columbitan .µ (/) ~ 0 ( Tirolites Tirolites .~ (/) Q) I or IJ w Q) 0 c: I:: ;>-, <O \J +' ·.µ- ~ 0 0 (lJ 0 m nondeposition ? _J (I) (I) Wasatch. ites ..£ +' I- E c f- <O Wasatch ites u L 0... E Owenitan 0 L - y... Neekoceras .Mee.koceras 0 (j) 4-- - ------ (f) L - ----- Q) <{ IO > L L 0) - -~ Flemingitan et. l/} Jll ...0 er Vl Q) c c 0 0 >.. E .~ -0 Q) c I L ".jJ +' «J 0 I- c L <II E .µ I- ro co 0... I u Propty_ch i tes E E (f) co 0 L L c E w L Gyronitan ~ ro 0::: 2 +' w c -2 ;>-, ::J .., Claraia Cl) 0 Qj L: ·----- Q) -go s m \) \J ::E: l.!J (/) iceras} Clara.id cf. stBChei I{) Cla.raia .L !)f!!!: ] >. -- 0 \) ----- - \J :J !/) 0 . 0 Otoce:ras ~ _J 0 ..£ Otoceratan 0 stachej__ stac.hei ..9- \j '9 s ~ :J (/) Ftaure J. CorreJadon Table, LOWER TRIASSIC FAUNAS THE LO\iil ER TRIAS SIC OF LIARD RIVER_. B .C. IN TRODUCTION In the autumn of 1943, E.D. Kindle of the Geological Survey supplied several interesting fossil collections of Lower Triassic a ge , obtained by him from the valley of Liard River, British Columbia. Their study has revealed the presence of two faunas , one of earlier Lower Triassic a ge and the other of later Lower Tria ssic age . The occurrence of the f auna s has already been made known i n frelimina.ry a1mouncements (Mc Learn and Kindle, 1943; Kindle , 1944 ) , and their stratigraphic r el ations have been desori'7~d 1 Dates within brackets r ef er to y ear of publication, and appear in list of r 0f erence s a t t he end of this r eport. (Kindl e , 1944) . It is proposed, in this mimeogr aphed r eport, to r eview their succession and location, to treat their correlation at some l ength, and to add a f ew note s on the fossils thems elves. In addition, the species a.r e illustra t ed in three printed plates, and t he new specie s ar e described i n an a ccompanying printed appendix. This may a lso be consider ed a s the third in a serie s of illustr ~ t e d r eports on the chara cteristic fossils of the Mesozoic formations of the west ern interior of Canada . The two preceding r eports a. r e : "Revision of the Lower Cretaceous of the We stern Interior of Canada", Geol. Surv., Canada , Pa.per 44-17, second edition; and 11 The Upper Cret a ceous Dunvegn.:n Formation of Northeastern British Columbia and Northwestern Alberta", Ge oL Surv.1 Canada, Pape!- 45-21. These r eports ar e designed for the geologist who wishes to be able to r ec ogni~ e f aunas in the field, and ther eby identify the formations in wh ich they occur. For this purpose , the illustra tions of fossils on the plates ar e arranged a ccording to f aunas and formations and not in the usual biological order. STR.A TIGRAPHY The name Grayling has been given by Kindle* to a 2 The stra tigr a phy of that part of Liard Ri ver basin from which the pr esent summary is t aken is discussed at l en gth by E .D. Kindle (1944). forma tion, 600 to 1,000 f eet thick, tha t outcrops on Grayling and Liard Rivers. It is composed of gr ey, soft, laminat ed shales with rare, sandy and ca lcar eous beds. Specimens of Clar a i a cf. stachei Bittner we r e collected by Kindle from this formation on the north bank of Liard Ri ver opposite the. west end of an island a bout 1-~- mileB east of . t he mouth of Crusty Creek (S ee l ocality A, Figure 1). Specimens of the same speci es wer o a lso obtained by Kindle from t a lus on the east bank of Toad River at its junction with the Liard (See locality B, Fi gure 1). - -2- The Toad formation overlies the Grayling conformably, and consists of black and brovm platy shales , siltstones, sandstones, and limestones (Kindle , 1944). It is 800 f eet thick near the mouth of Toad River, from which it r eceives its name , and nearly 2,400 feet t hick 9 miles to the wes t. Ki ndl e exami ned a. we ll-exposed section on t he north bn.nk of Liard River about 2 mile s north of the mouth of Toad River (See locality C, Figure 1). About 400 f eet above the base is s. thin bed of lime stone containing a Lower Tria ssic fauna with 'Prionites ~ hollandi n . sp ., \/ila sa tchi t es ca.nadensis n .sp ., W. meeki var. deleE:ni n.var ., Anavm.satchites to.rdus n.sp,, Ana.wasatchites merri'TI'in.-:Sp., Xenoceltites robertsoni n ,sp., X. cf. hannai Ma thews, X. n~rt nn i n . sp., Pseudomonotis ovn.lis Wh iteaves,-P. ovalis var. kindli - n.vn. r., and Orthocer a. s sp. Wa sn. tchites procurvus-n.sp. is probably fr om this loca lity. About 300 f eet higher stratigraphica.lly in the same section (Kindle , 1944) is a 2-foot bed of black, impure lime stone carrying a Middle Triassic (Anisian) fauna with species of the ammonoid gener a. Beyrichites, Sturia. , Par apopanocer a.s , etc. The Lower Tria ssic Wa satchites f auna ha s been collected in the same forma tion on t he northeast bank of Toad Ri ver about 2 mile! upstream f :·om its confluence with the Liard (S ee loca lity D, Figure l). Her e ar e Wasa tchites meeki var. deleeni n,var-:-;-Pseudomonotis ovalis Wh i teave s ; and P . ova.TrSVe.r. kindli n.var. These Lower Triassic faunas of t he Toad formation seem to have been almost ent~rely overlooked by McConnell in his descent of Li ard River in 1887 (See McConnell, 1890). Howe ver, he ma.de no col­ l ections below He ll Gate , where Kindle 's collections wer e found, all his fossils having been obtained f arther upst r eam at and between the Rapids of t he Drowned and He ll Gate (See Figur e 1). One specimen found by McConnell and described by Whiteaves (1889), Pseudomonotia ovulis, is of the Lower Triassic Wa satchites f auna, and, presU1!l8.bly, Lower Trias sic beds a s well as :~U ddle Triassic beds of ~h e Na thorstites zone a. r e exposed a t the Rapids of the Drowned , In f act, McConnelif s collection from this locality seems to have been a mixed one, repre­ sentative of more than one f aunal zone, At Hell Ga t e (See Figure 1), limes tone and sandy lime­ stone near the top of the Toad formation contain the Na thorstites fauna, which wa.s collected by McConnell in 1887 and by Kindle in 1944. This fauna does not appear to be pre sent in the east near the mouth of Toad River, in which dir e ~ tion, as previously noted, the formation thi~s and, thereby , may have lost t he higher horizons of the west. From other sections i n northea stern British Co lumb i a , i t is known that the Na thorstite s fauna overlies the Middle Triassic (Anisian) f auna mentioned in a. preceding par a graph . In northea stern British Columbia. the sequence of the known Lower and Middle Tria s sic faunas is as follows: Middle Tria ssic (I..e. dinian - Na thorstites f auna (Me so-Tria ssic) ( Anisian - Beyrichi tes fauna Lower Trii:\,s sic (Upper - Wa.sa tchites fauna.
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