Preliminary Bedrock Geology of the Mcbride River Area (Parts of NTS

British Columbia Geological Survey 129°10' Open File 2018-3

Grid north COL ISH UM Turnagain Lake IT B R IA B Magnetic Preliminary bedrock geology of True north

490,000 mE north G the McBride River area E Y O E 6,460,000 mN V L R

O GICAL SU PzJCC 129°05' Location map Magnetic

lJTs declination Parts of NTS Sheets 104H/14,15; 104I/02, 03, 06 19° 11.40' E Previous mapping in the region YT Convergence Atlin angle YT Terranes (after Nelson et al., 2013) Bram I. van Straaten and Sebastian J. Bichlmaier 0° 4.26' W This study CC Ancestral North America 58.5 ° 104J/10 104J/09 104I/12 104I/11 104I/10 104I/09 Intermontane terranes Dease Lake Approximate mean declination 2018 van Straaten et al. (2017) Stikinia (ST), Cache Creek (CC), Quesnellia for centre of map Dease Lake (QN), Yukon-Tanana (YT) and others Annual change, decreasing 17.2' Logan et al. (2012) Recommended citation Coast plutonic complex van Straaten, B.I. and Bichlmaier, S.J., 2018. Preliminary bedrock geology of the McBride River area. British Columbia Ministry of Energy, Mines and Petroleum Resources, British Columbia Geological Survey Open File 2018-3, 1:50,000 scale. ST Insular terranes van Straaten et al. (2012) 104J/07 104J/08 104I/05 104I/06 104I/07 104I/08

58°15' Stewart Outboard terranes 58°15' Evenchick and Thorkelson (2005) mJHMUvm

500,000 mE Geochronology data 0 2 4 km 1400 37 Gabrielse (1998) QN Sample Easting Northing Unit Age (Ma) Type Mineral Sample description Source Smithers 104J/02 104J/01 104I/02 104I/01 58 ° 104I/04 104I/03 Read and Psutka (1990) AN-78-467 493616 6434342 JMRgd 166±8 U-Pb Zrn Hbl-Bt-bearing granodiorite Anderson et al. (1982)* Prince Rupert 1:50,000 scale

Prince George t lJTgw AN-78-467 493616 6434342 JMRgd 184±8 U-Pb Zrn Hbl-Bt-bearing granodiorite (re-analysis of AN-78-467) Anderson and Bevier (1992)*

l Read (1984)

u AN-78-467 493616 6434342 JMRgd 186±13 K-Ar Hbl Hbl-Bt-bearing granodiorite Stevens et al. (1982a)*

a Universal Transverse Mercator Projection, North American Datum 1983,

f 17BvS-6-36 491425 6432627 JMRgd In prep. U-Pb Zrn Hbl-Bt granodiorite This study

1600 Anderson (1983) 1200 Zone 9 North, 20 m contour intervals CC a 11BVA31-232 478755 6434626 MJTSgr 169.1±0.8 U-Pb Zrn Hbl-bearing Bt monzogranite van Straaten et al. (2012)

ST o 104G/15 104G/16 104H/13 104H/14 104I/15 104I/16 

h 21 Read (1983) GAD 67-132-3 477914 6443782 MJTSqm 159±8 K-Ar Hbl Leucocratic Hbl-Bt-bearing Qtz monzonite or granodiorite Wanless et al.(1972), Anderson (1983)*

c 1800 e 128.5 ° - -130.5 °

-129.5 ° l 11BVA35-276 480640 6439273 MJTSqm 169.0±1.1 Ar-Ar Bt Hbl-bearing Bt Qtz monzonite to monzogranite van Straaten et al. (2012)

h 11BVA35-276 480640 6439273 MJTSqm 169.0±1.3 U-Pb Zrn Hbl-bearing Bt Qtz monzonite to monzogranite van Straaten et al. (2012)

QN e K AN-79-719-1 480471 6435640 MJTSqd.fg 150±4 K-Ar WR Fine-grained quartz diorite Stevens et al. (1982b)* Kamloops C’’’ 128°55' Legend (for detailed unit descriptions the reader is referred to van Straaten and Bichlmaier, 2018) 47 King Salmon fault 11BVA42-332 479794 6436014 MJTSqd.fg 173.2±1.4 Ar-Ar Hbl Fine-grained Hbl-Bt Qtz diorite van Straaten et al. (2012) 1400  17SBI-10-60 495568 6426021 mJBLcg In prep. U-Pb Zrn (D) Medium grained sandstone This study Stratiﬁed rocks 17SBI-16-88 496183 6435581 mJHMUvf In prep. U-Pb Zrn Felsic tuff This study Overlap assemblages Vancouver 17SBI-37-301 498815 6431164 mJHMUvf In prep. U-Pb Zrn Flow-banded Pl porphyry This study 117c, 118b, lmJHMMv, Flow-banded maroon Pl-phyric volcanic rock, grey Aug-Pl Miocene-Pleistocene, Tuya Formation 119b, SphRhy 493980 6429991 EMJf(?) 191±9 Rb-Sr WR crystal tuff, grey Aug-Pl-phyric volcanic rock, spherulitic rhyolite Erdman (1978) Victoria 17BvS-19-159 481756 6441786 lmJHMLvf In prep. U-Pb Zrn Felsic lapillistone to lapilli tuff This study MPTvm Olivine basalt 1600 55 17BvS-25-238 498661 6447266 lJTLcg In prep. U-Pb Zrn (D) Polymictic conglomerate with limestone and volcanic clasts This study  Cretaceous, Sustut Group 17BvS-25-242 500472 6447222 lJTLsv In prep. U-Pb Zrn (D) Feldspathic arenite to volcaniclastic sandstone This study AN-79-718-1 481553 6434837 LTrCHqm.le 142±53 K-Ar Hbl Leucocratic Hbl granodiorite Stevens et al. (1982b)* KSs Undivided sedimentary rocks

1800 E AN-79-718-1 481553 6434837 LTrCHqm.le 185±28 K-Ar Hbl Leucocratic Hbl granodiorite Stevens et al. (1982b)* 34 m unconformity

0 128°50' 0 0 I100  , 11BVA38-304 481362 6439991 LTCHgr 216.2±1.2 U-Pb Zrn Hbl-bearing granodiorite to monzogranite van Straaten et al. (2012) Stikinia 0

1600 1

5 Middle Jurassic, Bowser Lake Group

1 * Location digitized from 1:100,000 scale map (Gabrielse, 1998, Figure 14) 6

0 mJBLs Sandstone, conglomerate and shale

0 0 PzJCC 88 1400 0 Wade Lake 6,450,000 mN  26  I093 I101 mJBLv Mafic volcanic rocks Fossil data Lower to Middle Jurassic, upper Hazelton Group lmJHMMv lJTLv Middle Jurassic, Horn Mountain Formation ePli Location F F lPli Sample GSC number Easting Northing accuracy* Unit Age Fossil descriptions Identified by Source lPli 64 F lPli mJHMUvm F lJTgw n/a 95019 498997 6441623 moderate mJBLs early Bajocian Poorly preserved inner whorls of ammonite (Sonniniids? indeterminate forms) H. Frebold and H.W. Tipper Gabrielse (1998) Upper mafic volcanic rocks 39 64  n/a 95018 499468 6441405 moderate mJBLs early Bajocian Fragment of ammonite (indet., possibly inner whorl of a sonniniid) H. Frebold and H.W. Tipper Gabrielse (1998)  Impressions and poorly preserved fragments of ammonite (sonniniids, sp. indet.), bivalves mJHMUvf 45 F lPli lJTLsv  n/a 95024, 95023, 95020 498788 6441830 moderate mJBLs early Bajocian H. Frebold and H.W. Tipper Gabrielse (1998) Upper felsic volcanic rocks F F ePli (Myophorella sp., Trigoniids, other indeterminate forms), indeterminate corals Indet.F  68 Ammonites (Fragments and distorted specimens of Chondroceras spp. indet., fragments and poor

ePli n/a 95016 502494 6439876 moderate mJBLs early Bajocian impressions of Stephanoceras s.l.), various brachiopods, pelecypods, gastropods H. Frebold Gabrielse (1998) Lower to Middle Jurassic, Horn Mountain Formation

E In prep.  C 0

m F lSin-ePli 0 0 mJBLs Toarcian to

2 493048 6444024 low Belemnites (indet.) J. A. Jeletzky Gabrielse (1998) lmJHMMv Middle maroon volcanic rocks 0 n/a 95241

In prep. 0

31 1 or lJTL early Aptian

0 0 8

4  lSin  4 C 0

0 75 mJBLs late Pliensbachian to

0 1

In prep. 0 58°10' 24 0 lJTLcg F 0 n/a 95240 493583 6444607 moderate Belemnites (Nannobelus?), indeterminate pelecypods, indeterminate brachiopods J. A. Jeletzky Gabrielse (1998)

0 F lPli 58°10' or lJTL early Toarcian 1400 6 F 0 58°10' 8 A’’ F lmJHMLvm Lower maﬁc volcanic rocks

 6 D

1 1 lPli-Toar lPli(?) D In prep. 8

40 128°45'

EMJm 1 0 H. Frebold, H.W. Tipper, G.

15 35 lJTLsv 1 n/a 95025, 95026 481195 6439799 moderate lmJSPs Toarcian Ammonite (probably Hildaites sp. ind., other gen. et sp. indet.) Gabrielse (1998)  0 1200  Jakobs 1600 4  uTrSls

' 40

5 62 1 Ammonites (Peronoceras verticosum?, Zugodactylites? sp. ind., Harpoceras?, sp. ind., lmJHMLvs 1 I009 Lower volcaniclastic sandstone °  n/a 95093 481159 6441653 moderate lmJSPs middle Toarcian H. Frebold and G. Jakobs Gabrielse (1998) 1 1800 9 Phymatoceras? sp. ind.) 2 8 lSin 40 1 lJTLcg F 72 0 n/a 95251 482474 6441083 moderate lmJSPs Toarcian? - Bajocian Belemnite (Belemnopsis sp. indet.) n/a Gabrielse (1998) Lower to Middle Jurassic, Spatsizi Formation lmJHMLvm 0  EMJm.po lJTLv C In prep. n/a 95098 499935 6449077 moderate lJTgw late Pliensbachian Ammonite (Arieticeras cf. A domarense (Meneghini)) H. Frebold Gabrielse (1998) 1 28 lJTLv 0 7 Fragments of ammonites (Amaltheus sp. Margaritatus Group, Protogrammoceras spp. indet.), 1 lmJSPs Argillite, siltstone and sandstone 0  n/a 95021 501627 6448949 moderate lJTgw late Pliensbachian H. Frebold and H.W. Tipper Gabrielse (1998) 2  0 bivalves (Weyla, trigoniids, others), corals

0 lndet. F unconformity 0 lJTLsv Ammonites (Protogrammoceras spp., Arieticeras cf. algovianum (Oppel), Amaltheus spp., 1 1400 F lSin(?)  n/a 94994, 90991, 94986 501834 6447339 moderate lJTgw late Pliensbachian H. Frebold and H.W. Tipper Gabrielse (1998) 4 Triassic, Stuhini Group 1 Aveyroniceras spp., Leptaleoceras aff. accuratum (Fucini)), bivalves (trigonids, Weyla?) 0 1 2000 8

0 6 26 lJIs Ammonites (Protogrammoceras?, or Fuciniceras? sp. indet., poor impressions of whorl fragments,

0 n/a 95258, 95257, 95268 494106 6448453 moderate lJTgw late Pliensbachian H. Frebold and H.W. Tipper Gabrielse (1998) 0 F lSin 17 0 lJTLcg  Prodactylioceras aff. P. italicum (Meneghini), Prodactylioceras aff. P. meneghinii (Fucini) Maﬁc volcanic rocks 0 1  1800 TrSTvm 1600 eToar(?) F 6 F I010 Ammonites (Arieticeras spp. indet. impressions of small specimens, Protogrammoceras spp., 0 lSin n/a 94995 494096 6448922 moderate lJTgw late Pliensbachian H. Frebold and H.W. Tipper Gabrielse (1998) MJTSqm dactylioceratid impression of inner whorl, Amaltheus sp.)

0 38 Devonian-Permian, Stikine assemblage

 1600 MJTSgr  53 lJTLs 17SBI-25-149 V-003872 500357 6448252 high lJTgw early Pliensbachian Ammonites (Tropidoceras) T.P. Poulton Poulton (2017) lJTLv Ammonites (Coeloceras? sp., Phylloceras spp., derolytoceratid?, Gemmellaroceras sp., 1800 mJBLs F lPli-eToar n/a 90992, 95269 498494 6449118 moderate lJTgw early Pliensbachian H. Frebold and H.W. Tipper Gabrielse (1998) DPSsv Phyllitic greenstone and phyllite 1400 polymorphitid spp., inner whorls of Tropidoceras cf. erythraeum?, Miltoceras? Sp.) 42 1400 Tectonic Sin F late Sinemurian to Ammonites (eoderoceratacean genera Eoderoceras, Eteoderoceras, Metaderoceras, and perhaps 17SBI-25-148 V-003871 500244 6447909 high lJTgw T.P. Poulton Poulton (2017)

 lJTLsv 1600 early Pliensbachian Crucilobiceras) contact 42  lJTLs 67 Whitehorse trough Toar-eApt F Faint impressions and poorly preserved fragments of ammonites (harpoceratid, Arnioceras?, other  45 1200 n/a C-95096, 95091, 95101 499982 6445190 low lJTL early Toarcian(?) H. Frebold and G. Jakobs Gabrielse (1998) 44  uTrSls gen. et sp. indet.) Lower Jurassic, Laberge Group

EMJm.po 24 C In prep. 159±8 K   C late Pliensbachian to Ammonites (Dactylioceratidae, gen. et sp. indet, impressions of small fragments of H. Frebold, H.W. Tipper, G. 1200 n/a 95261 - 95266 497969 6447378 moderate lJTLs Gabrielse (1998) Lower Jurassic, Takwahoni Formation lmJSPs 2000 A’ F Sin 1400 Toarcian Protogrammoceras? sp. indet., Harpoceras sp. ind., Hildaites sp. ind., other gen. et sp. indet.) Jakobs 2 61 lNor-eRhae

0 22 11  Very poorly preserved small ammonites (Protogrammoceras sp. indet., impression of a distorted 0 n/a 95269 499759 6447274 moderate lJTLs late Pliensbachian(?) H. Frebold and H.W. Tipper Gabrielse (1998) 1800 50 fragment of Arieticeras? sp. indet. showing keel with shallow sulci) lJTs Siltstone with lesser feldspathic arenite 1 0   EMJm.po uTrSls 1200 6  1 0 70 n/a 94991 8 493457 6448295 moderate lJTL? early Pliensbachian Poorly preserved ammonite (Dubariceras sp. indet.) H. Frebold and H.W. Tipper Gabrielse (1998) 0 MJTSqd lmJHMLvs 0 lJTgw Feldspathic wacke, feldspathic arenite and lesser siltstone 0 Ammonites (Paltechioceras cf. rothpletzi (Bose), coarsely ribbed Paltechioceras sp., 1600 n/a 95015 500005 6447324 moderate lJTLs late Sinemurian H.W. Tipper Gabrielse (1998)  In prep. C Plesechioceras? sp. Phylloceras sp.), many genera and species of bivalves  60 24 Lower unit 1400 n/a 95094 501877 6446596 moderate lJTLs late Sinemurian Ammonites (Paltechioceras sp., Phylloceras sp.), numerous and varied bivalves H.W. Tipper Gabrielse (1998) lmJHMLvm Kehlechoa  1200 Ammonites (Paltechioceras cf. harbledownensis (Crickmay), faint impression of Crucilobiceras sp. Volcaniclastic sandstone facies

C’’ fault n/a 94993, 90996 501319 6445156 moderate lJTLs late Sinemurian H. Frebold and H.W. Tipper Gabrielse (1998) lJTLsv

46 128°45' indet. showing two rows of spines, Juraphyllites n. sp.?), wide variety of bivalves :  2  37 F eBaj

1 0 n/a 95099 495094 6445413 low lJTLs late Sinemurian Ammonites (Gleviceras sp., and aptychi) H.W. Tipper Gabrielse (1998) r 1  1 0

8 F U In prep. 0 F eBaj lJTLv Maﬁc volcanic facies 6 0 13

0 mToar 0 e 64

0 0 0 n/a 94990 493492 6445755 moderate lJTLs late Sinemurian? Poorly preserved ammonite fragments (Astroceras?) H. Frebold and H.W. Tipper Gabrielse (1998) F eBaj

0 Toar?-Baj v

mJBLs

F i n/a 95256 499937 6444329 moderate lJTLs Sinemurian Fragments of a small ammonite (probably Arnioceras) H. Frebold Gabrielse (1998) lJTLs Argillite and siltstone facies

65 

63 R Ammonites (Epophioceras aff. E. carinatum Spath, Gleviceras sp., Arnioceras sp., Asteroceras cf.

n/a 95092, 95095 499920 6443564 moderate lJTLs? Sinemurian H. Frebold and H.W. Tipper Gabrielse (1998) A. varians Fucini)

128°50' lJTLcg Conglomerate facies LTrCHgr

54 e n/a 95051, 95057 500570 6445754 moderate lJTLs Indet. n/a n/a Gabrielse (1998)

 75 unconformity  d

216.0±1.2 Upper Triassic, Sinwa Formation i n/a 95107 493137 6448199 low lJTL? Indet. Bivalves, indet. E.T. Tozer Gabrielse (1998)

6,440,000 mN

U r eBaj

Limestone 169.0±1.1 Ar Toar F 17SBI-22-123 V-003861 501320 6447523 high In prep. In prep. M.L. Golding Golding, pers. comm. uTrSls Limestone

 block in lJTLsv Tectonic F B

 Limestone A c 17SBI-23-125 V-003862 499851 6447971 high In prep. In prep. M.L. Golding Golding, pers. comm. contact

clasts in lJTLsv Cache Creek

24 1800 MJTSgr M late Norian - early Hexacorals (indet.), fragmentary pelecypods (indet.), ichthyoliths, conodonts (Mockina bidentata M. J. Orchard and M.L Gabrielse (1998); 169.0±1.3 U 499412 6443716 moderate uTrSls 33 n/a C-117416 Rhaetian (Mosher 1968); Mockina englandi (Orchard 1991)) Golding Golding et al. (2017) Paleozoic to Jurassic JMRgd 1200 : 1600 17BvS-23-208 V-003859 501349 6442602 high uTrSls In prep. In prep. M.L. Golding Golding, pers. comm. PzJCC Undivided 17BvS-23-212 V-003860 500535 6443750 high uTrSls In prep. In prep. M.L. Golding Golding, pers. comm. 1400 2000 17SBI-28-192 V-003863 512188 6446347 high uTrSls In prep. In prep. M.L. Golding Golding, pers. comm. Lower Jurassic, Inklin Formation MJTSqm 1800

MJTSqd  UTM NAD83 Zone 9N Feldspathic wacke, siltstone and phyllite 58°05' lJIs

20 1200 58°05' * Location accuracy: High - GPS measurements (this study); Moderate - digitization of fossil locations from 1:100,000 scale map (Gabrielse, 1998, Figure 14); Low - converted from latitude-longitude (Gabrielse, 1998, appendix 2) 1400  MJTSgr Upper Triassic, Sinwa Formation 1600 mJBLs MJTSgr LTrCHqm 42 EMJf uTrSls Limestone 0 LTrCHqm 0 1200 4 1

 lmJHMMv Schematic vertical cross-sections

1 : 7 1600 4

1  Whitehorse

0 Intrusive rocks

6 0 0 0

0 1400 Stikinia trough 2 8 Symbols Jurassic, McBride River pluton

1 1800 Spatsizi Cake Hill

173.2±1.4 Ar MJTSqm 1 :

8 pluton 0 JMRdr.fg  Fm. Horn Mountain Formation Takwahoni Fm. 0 JMRgd Hornblende-biotite granodiorite In prep. U 26 Field station: 2011; 2015; 2017 K 150±4 1000

MJTSqm MJTSqd.fg JMRdr Hornblende-clinopyroxene(?) diorite to quartz diorite  Kehlechoa fault Minﬁle (104)

184±8 U  2 JMRdr.fg Maﬁc-rich microdiorite

MPTvm EMJf 19 7 mJBLs  F C U  Sample site: fossil, conodont 169.1±0.8 142±53 K K 185±28 186±13 K 1600 Middle Jurassic, Three Sisters pluton LTrCHqm.le mJHMUvf MJTSgr Biotite monzogranite  26 15 I027 10 Geochronology sample site: U-Pb zircon, U-Pb detrital zircon, Ar-Ar, K-Ar, Rb-Sr U D Ar K Rb MJTSgr EMJm 

: 6 mJBLv 0 1 MJTSqm Biotite quartz monzonite 0

: 128°55' B 4 Bedding: tops unknown; tops known, right-way-up; tops known, overturned

1   

0 

TrSTvm 0 MJTSqd Hornblende-rich quartz diorite

33 6 Elevation (km)

lmJHMMv 1 

mJBLs mJBLv Foliation

  0 MJTSqd.fg Fine-grained hornblende-biotite quartz diorite

In prep. U rSTvm  Contact: deﬁned, approximate, inferred from aeromagnetic data, inferred

T 74 11 A A’ A’’ Early to Middle Jurassic, Horn Mountain intrusions  

mJHMUvf B’ 14 12 Unconformity: deﬁned, approximate, inferred EMJf Felsic intrusive 1600 52 28  1800 65 EMJf EMJm.po Platy plagioclase porphyry

MJTSgr 1400 : Stikinia Fault: defined, approximate, inferred from aeromagnetic data, inferred  In prep. U Mafic intrusive 1600 EMJf I016 McBride River Horn Mountain Formation Bowser Lk. Gp. Horn Bowser Lk. Gp. Normal fault: defined, approximate, inferred from aeromagnetic data, inferred EMJm

JMRgd mJBLv pluton Mtn Fm.  24 : (dot on hanging wall) Late Triassic, Cake Hill pluton EMJm C’- C’’

1200 ? Thrust fault: deﬁned, approximate, inferred from aeromagnetic data, inferred 11  LTrCHgr Hornblende granodiorite to monzogranite mJBLs 0

0 (tooth on hanging wall)

 1 2 26 0 6,430,000 mN  Rb 191±9 6 LTrCHqm Hornblende quartz monzodiorite 1400 1000 1 Altered or gossanous rocks 1200 7 B’’

: 8 EMJf I015 mJBLs

LTrCHqm I021 2000 LTrCHqm.le Leucocratic hornblende quartz monzodiorite   Outcrop (darker shade) 1000 1400 1 46 58°00' 49 800 1600 58°00'

H030 H029 H010

Elevation (km)

H009   1200

30 mJHMUvf 0  25 1400 :

EMJf mJBLs H028 B B’ B’’  17 JMRdr 1800 28 C’ Cache

:  Whitehorse trough 1200 Stikinia Creek

: Gp. Lk. 15 Sinwa Fm. McBride River

EMJm.po Bowser

1600 Sustut Group Horn Mountain Bowser Lake Group Horn Mountain Formation Bowser Lake Group Takwahoni Formation lower unit Takwahoni Formation greywacke unit  H007 Formation pluton B’- B’’ 1 D In prep. 4 :

1 1

0 1

4 29 1 2

0 6

2 0

0 0

0  1 0 0 Mt. Sister Mary

0 0 1 0 1400 0 0 0 King Salmon fault 0 800 2 0 26 Kehlechoa fault 1200 Pitman fault JMRdr.fg : mJBLs H027 JMRdr.fg ? 1000 lmJHMMv MJTSgr 1 8 0 : 0 lmJHMMv Elevation (km)

0 129°15' 129°20' 0 1200 8 1400 0 1200 C C’ C’’ C’’’

1000 References : 1000 8 00 Anderson, R.G., Loveridge, W.D., and Sullivan, R.W., 1982. U-Pb isotopic ages of zircon from the Jurassic plutonic suite, Hotailuh Batholith, north - central British Columbia. Poulton, T.P., 2017. Report on an examination of photographs of Early Jurassic ammonites collected from the Takwahoni Formation in Cry Lake map area east of Dease Lake and Data sources:

In:Current Research, Part C, Geological Survey of Canada paper 82-1C, pp. 133-137. near McBride River, NW British Columbia (NTS 104I) and submitted October 6, 2017, by Bram van Straaten, British Columbia Geological Survey. Geological Survey of Aeromagnetic data: Aeroquest Airborne, 2012. Report on a helicopter-borne magnetic survey (Aeroquest Job #11-046) for Geoscience BC. Geoscience BC Report 2012-2, 11p.  mJBLs Anderson, R.G., 1983. Geology of the Hotailuh batholith and surrounding volcanic and sedimentary rocks, north-central British Columbia. Unpublished Ph.D. thesis, Carleton University, Canada, Palentological Report, Fossil Report 11-2017-TPP, 6p. Pitman fault Ottawa, Ontario, Canada, 669p. Read, P.B., 1983. Geology, Classy Creek (104J/2E) and Stikine Canyon (104J/1W), British Columbia. Geological Survey of Canada Open File 940, 1:50,000 scale. Minfile: MINFILE BC mineral inventory, BC Ministry of Energy and Mines, https://minfile.gov.bc.ca/. Accessed June 2016. 31 Anderson, R.G., and Bevier, M.L., 1992. New late Triassic and early Jurassic U-Pb zircon ages from the Hotailuh Batholith, Cry Lake map area, north - central British Columbia. Read, P.B., 1984. Geology, Klastine River East (104G/16E), Ealue Lake West (104H/13W), Cake Hill West (104I/4W) and Stikine Canyon East (104J/1E), British Columbia. In: Radiogenic age and isotopic studies: Report 6, Geological Survey of Canada Paper 92-02, pp. 145–152. Geological Survey of Canada Open File 1080, 1:50,000 scale. Topographic data: BC Terrain Resource Information Mapping Digital Map Products, BC Ministry of Forests, Lands and Natural Resource Operations, Crown Registry and Geographic Base Branch, Erdman, L.R., 1978. Petrology, geochronology and geochemistry of Jurassic volcanic and granitic rocks of the Cry Lake and Spatsizi map sheets, north-central British Columbia. Read, P.B., and Psutka, J.F., 1990. Geology of Ealue Lake East-half (104H/13E) and Cullivan Creek (104H/14) map areas, British Columbia. Geological Survey of Canada Open File http://geobc.gov.bc.ca/base-mapping/atlas/trim/. Accessed June 2017. Unpublished B.Sc. thesis, The University of British Columbia, Vancouver, B.C., Canada, 63p. 2241, 1:50,000 scale. Evenchick, C.A., and Thorkelson, D.J., 2005. Geology of the Spatsizi River map area, north-central British Columbia. Geological Survey of Canada Bulletin 577, 276p, 1:250,000 Stevens, R.D., DeLabio, R.N., and Lachance, G.R., 1982a. Age determinations and geological studies, K-Ar isotopic ages, Report 15, Geological Survey of Canada Paper 81–2, 56p. Mapping by Bram van Straaten (2011, 2015, 2017), Sebastian Bichlmaier (2017) and JoAnne Nelson (2015) scale. Stevens, R.D., DeLabio, R.N., and Lachance, G.R., 1982b. Age determinations and geological studies. K-Ar isotopic ages, Report 16, Geological Survey of Canada Paper 82–2, Geology compiled by Bram van Straaten and Sebastian Bichlmaier Gabrielse, H., 1998. Geology of Cry Lake and Dease Lake map areas, North-Central British Columbia. Geological Survey of Canada Bulletin 504, 147p, 1:250,000 scale. 56p. 800 KSs Sebastian Bichlmaier and Bram van Straaten Golding, M.L., Orchard, M.J., and Zagorevski, A., 2017. Conodonts from the Stikine Terrane in northern British Columbia and southern Yukon. Geological Survey of Canada, Open van Straaten, B.I., Logan, J.M., and Diakow, L.J., 2012. Mesozoic magmatism and metallogeny of the Hotailuh Batholith, northwestern British Columbia. British Columbia Ministry Cartography by File 8278, 24 p. of Energy, Mines and Natural Gas, British Columbia Geological Survey Open File 2012-06, 58p, 1:50,000 scale. DPSsv S t i k i n e R i v e r Logan, J.M., Moynihan, D.P., Diakow, L.J., and van Straaten, B.I., 2012. Dease Lake - Little Tuya River geology (NTS 104J/08, 07E). British Columbia Ministry of Energy, Mines and van Straaten, B.I., Gibson, R. and Nelson, J., 2017, Preliminary bedrock geology of the Tanzilla and McBride area. British Columbia Ministry of Energy and Mines, British Acknowledgements: Natural Gas, British Columbia Geological Survey Open File 2012-04, 1:50,000 scale. Columbia Geological Survey Open File 2017-9, 1:50,000 scale. We thank Marc Beaton and Rachel Gavin for their capable and enthusiastic assistance during the field season, and Tundra Helicopters for safe flying. We also thank Terry Poulton (Geological Survey of Canada, Calgary) 6,420,000 mN Nelson, J.L., Colpron, M., and Israel, S., 2013. The Cordillera of British Columbia, Yukon and Alaska: Tectonics and metallogeny. In: Colpron, M., Bissig, T., Rusk, B. G., and van Straaten, B.I., and Bichlmaier, S., 2018. Late Early to Middle Jurassic Hazelton Group volcanism and its tectonic setting, McBride River area, northwest British Columbia. In: for providing macrofossil age determinations and Richard Friedman (University of British Columbia, Vancouver) for providing preliminary U-Pb zircon geochronology results. Thompson, J. (Eds.), Tectonics, metallogeny and discovery: The North American Cordillera and similar accretionary settings, Society of Economic Geologists Special Geological Fieldwork 2017, British Columbia Ministry of Energy, Mines and Petroleum Resources, British Columbia Geological Survey Paper 2018-1, pp. 39-66. Publication 17, pp. 53–110. Wanless, R.K., Stevens, R.D., Lachance, G.R., and Delabio, R.N., 1972. Age determinations and geological studies. K-Ar isotopic ages, Report 10, Geological Survey of Canada

129°00' Paper 71–2, pp. 96p. 57°55' 129°10' C 129°05' 57°55'