Bedrock Geology Compilation Map Series: Caribou River NTS

0 0 0 0 0 0 O O O O O O

Published 2005 Published

59 57 55 53 51 49 54A 0 O

92 54B

Manitoba Geological Survey Geological Manitoba B.G.C.M. Series 54M, 1:250 000 NTS River, Caribou 53O

- with River

Nn 0

O Ontario - with hybrid with - H U D S O N Y A B Williston Basin KILOMETRES Superior Province Churchill Province Hudson Bay Basin 92 garnet garnet Zh

biotite poikiloblasts

a - pink porphyritic a - 53N

54C River 53K G

PHANEROZOIC

s PRECAMBRIAN

54F

pegmatite d o

0 50 100 150 200 250 54K River

Hayes

Lake

Churchill Gods

aplite

Lake tourmaline andalusite River

b - granite gneiss, + biotite granite + b -

53E

53L

53M 54D 54E River

54L Island SYMBOLS

52E 52L

53D 52M 54M 0

Nelson

Winnipeg 96 Churchill garnet

River

LEGEND Minnesota

NTS 54M River - pink porphyritic granite; pink porphyritic - - hypersthene granite and hypersthene gneiss and hypersthene granite hypersthene - 64I 63I 62I

62P

64P 63P

63A 63H 62H

64H

64A

Nunavut

Seal Red WINNIPEG Gp Zm

Southern

Indian

Geological boundary (approximate, interpreted) (approximate, boundary Geological Fault interpreted) (defined, zone boundary Shear overturned) Bedding, vertical, (inclined, tops known amount of vertical, dip unknown) (inclined, layering Metamorphic amount of (inclined, dip unknown) topsIgneous unknown layering, amount of vertical, dip unknown) (inclined, Gneisossity Schistosity amount of vertical, dip unknown) (inclined, Cataclastic foliation (inclined) plunge indicated) lineation (inclined, Mineral plunge indicated) fold axis (inclined, Minor dip indicated) fold axial plane (inclined, Minor S-shaped, symmetrical) (Z-shaped, fold symmetry Minor boundary Domain outcrop of no Precambrian littleArea or Esker River

Lake

WINNIPEG

Thompson magnetite Granite; amphibolite; with granite granite Hybrid bearing, Tonalite, cordierite metabasic rocks noritic; in part Metagabbro, toSemipelitic metatexite, paragneiss + garnet; bearing tonalite, cordierite diatexite to biotite metatexite, Granodiorite gneiss and foliated tonalitic to lineated to granodioritic Grey to tonalite biotite granodiorite gneiss Hypersthene (monzocharnockite); granite Hypersthene foliated, to massive Granite, phyllite to biotite- pale green and interlayered Quartzite muscovite schist, phyllite, to grey-green Grey and serpentinite Ultramafic Gabbro diorite quartz to porphyritic Granodiorite Archean) tuff andesite (probably and pillowed Interlayered basalt Andesite and minor diatexite to biotite metatexite, Granodiorite and black pyritic meta-argillite and black acicular amphibole- acicular and black meta-argillite pyritic and black garnet granite;

LAKE

64O CARIBOU RIVER

64J

64G

64B M 63O

0 63J

O 63G

63B

62O 62J

62G

LAKE Assiniboine 100

North Dakota

MANITOBA v 0

Brandon P x O Q T B B V V N U G G G G G Z Tn

En Lake Gh INDEX MAP AND MAJOR TECTONIC DIVISIONS GI GI R Cedar 100

64N Seal River Volcanic Rocks Volcanic River Seal Hudsonian Hudsonian Group Island Great Rocks Intrusive River Seal n

64K a w LAKE 64F e 64C

h WINNIPEGOSIS 63N 63K NEJANILINI DOMAIN Proterozoic Archean GREAT ISLAND DOMAIN Proterozoic Archean and/or Proterozoic Archean tc

63F

Lynn Lake a 62N 63C 62K k 62F s

a The Pas

Flin Flon S Saskatchewan BEDROCK GEOLOGY COMPILATION MAP SERIES 0 0 0 0 0 0 O O O O O O 59 57 55 53 51 49 0 O 0 ’ 0 59 0 ’ O 0 0 0 0 ’ O O

65 000 O 0

50 59 O 0 60 66 000 O

00 15 60 94 94 Printed 2005 Printed 30 94 0 6650000 O 45 0 50 -50 800 600 500 400 350 300 250 200 150 100 -100 -150 -200 -250 -300 -350 -400 -500 94 1000 Gammas 0 O 0 O 59 0 O 60 0 O 94 94 GEOLOGICAL DOMAINS 10 Km0 1020304050Km

NEJANILINI DOMAIN NEJANILINI GREATDOMAIN ISLAND 0 O 0 O 0 96 O 0 96 O 60 59 0 ’ 0 ’ 10 30 30 Km0 1020304050Km

RESIDUAL TOTAL FIELD SHADED RELIEF

B A Y A B H U D S O N O S D U H

37’ E O Magnetic North Magnetic 0 North 0 O 0 O 0 96 O 0 96 O 60 Decreasing 6.0’ annuallyDecreasing

(2005) for centre of map

Point Hubbart 59 Approximate mean declination mean Approximate 000

of the Woods of Point 4 2, in 000 Hudson 00 4 G Nunalla Report of Field G

Hudson orogenic The Knoll The in Hudson hinterland, G terozoic Volcanic Suites,

Hudson Orogen in northern

28, p. 239–261. R i v e r e v i R Gp utonism in the Churchill Province , v. 17, p. 333–347. x

Z R I V E R E V I R Paper 1338–1354. 0

0 R i v e r O O Gp G 95 95 v. 30, p.

R i v e r G Gp

Scale 1:250 000 a r e v i R Canada, Special

G S E A L A E S eries, NTS 64P, scale 1:250 000. V B Whiskey Jack Lake (north half) area (Kasmere Project); Hudson Orogen, northern Saskatchewan, Canada; Canadian Tn Metamorphism in the Canadian Shield, Geological Survey of G Geochemistry and Mineralization of Pro V in in Summary of Investigations 1997, Saskatchewan Geological Survey, 10, p. 139–154.

R I V E R

S e a l in E g g g E 33, p. 147–166. Gp Pb age on zircon from a granite pluton, Kamilukuak Lake area, District of Keewatin, 5 Evolution of Archean Supracrustal Sequences, L.D. Ayres, P.C. Thurston, K.D. Card and W. Saskatchewan, Canada; T.C. Pharoh, R.D. Beckinsle and D. Eickard, (ed.), Geological Society of London, Special Publication northern Saskatchewan; Canada, Paper 78- in Weber (ed.), Geological Association of estabishes a lower limit for the age of Christopher Island Fromation, Dubawnt Group; Radiogenic Age and Isotopic Studies: Report Survey of Canada, Paper 87- 1, Geological p. 67–71. Geochronological studies of Precambrian rocks from the southern District Keewatin; Geological Survey of Canada, Paper 88-18, 36 p. Geology of the Courtenay Lake Formation in Cook Area, Wollaston Domain, northern Saskatchewan; p.Saskatchewan Energy and Mines, Miscellaneous Report 97-4, 115–120. Nejanilini Lake, NTS 64P; Manitoba Industry, Trade and Mines, Geological Survey, Bedrock Geology Compilation Map S belt, Canada; Geological Society of America Bulletin, v. 104, p. 1073–1085. Canada; Geology, v. 19, p. 1137–1140. The age and geological history of the Wollaston, Peter Lake Rottenstone domains in northern Saskatchewan; Canadian Journal Earth Sciences Geology of the Cochrane and Seal Rivers area; Manitoba Energy Mines, Minerals 139Division, Geological Report GR80-9, p. Orogen; Canadian Journal of Earth Sciences, Activities, Manitoba Energy and Mines, Minerals Division, p. 1986, 207–210. Journal of Earth Sciences, v. 24, p. 407–424. Manitoba Department of Mines, Resources and Environmental Management, Mineral Resources 163Division, Geological Services Branch, Publication 74-2, p. Geology and geochronology of the Wollaston Lake Fold Belt in northwestern Manitoba; Canadian Journal of Earth Sciences, v. 12, p. 1749–1759.

Lk Crave

Nunavut

Manitoba Gh

Lake

Esker b 1987: U-Pb geochronolgy of accreted terranes in the Trans- 1985: the western Churchill Province and its significance; Variation in character of Archean rocks 1987: A U- 1978: Metamorphic patterns and their relation to tectonism pl 1988: 1997: 2002: 1992:Batholith:Wathaman The an Early Proterozoic continental arc in the Trans- 1991: Hurwitz Group, Trans- New geological limits on the depositional age of 1980: 1986: 1993: Regional setting and kinematic features of the Needle Falls Shear Zone, Trans- 1986: U-Pb zircon geochronology of the Big Sand Lake area in northern Manitoba; 1987: U-Pb geochronology in the Trans- 1975a: Geology of the Kasmere Lake– 1975b:

Sothe G Gp Kilometres 0 5 10 15 20 25 Kilometres

Haywood Lake G

Lewry, J.F., Macdonald, R., Livesey, C., Meyer, M., Van Schmus, W.R. and Bickford, M.E. Lewry, J.F., Sibbald, T.I.I. and Schledewitz, D.C.P. Loveridge, W.D., Eade, K.E. and Roddick, J.C. Lewry, J.F., Sibbald, T.I.I. and Rees, C.J. Loveridge, W.D., Eade, K.D. and Sullivan, R.W. MacNeil, A., Delaney, G.D. and Ansdell, K. Manitoba Industry, Trade and Mines Meyer, M.T., Bickford, M.E. and Lewry, J.F. Patterson J.G. and Heaman L.M. Ray, G.E. and Wanless, R.K. Schledewitz, D.C.P. Stauffer M.R and Lewry J.F. Van Schmus, W.R. and Schledewitz, D.C.P. Van Schmus, W.R., Bickford, M.E., Lewry, J.F. and Macdonald, R. Weber, W., Schledewitz D.C.P., Lamb, C.F. and Thomas, K.A. Weber, W, Anderson, R.K. and Clark, G.S. C l a r k e k r a l C Zh

Morris in N

N Lake

D i c k i n s Tn R I V E R P G Summary

L i t t l e The Early v GI Q in GI in

Vinsky Lake 0 ’

0 Long SELECTED BIBLIOGRAPHY ’

The Early Proterozoic Russell L A E S 30 G

Esker 30 in

Lake Zh Gh The Early Proterozoic Trans- Nn N Zh in Simundson C A R I B O U Tn x G Z G 000 Gh 50

Schoenthaler Gh 3 a N

Lake G G 000 Summary of Investigations 1997, Saskatchewan 50 N 3 b

McEwen Lake x Z

Mikolash

Lake in

Warner G

Lake G Gp Tn

Island Zm

McMurchay T Current Research, Part C, Geological Survey of Canada, Paper 89- Summary of Investigations 1995, Saskatchewan Geological Survey, Zm in G U

R i v e r in Gp

Zh Lake

Zh K i r k

element and Rb-Sr whole-rock isotopic constraints on the origin of Chipewyan, Pakulak G G En Zh x Z x Gh b of Investigations 1992, Saskatchewan Geological Survey, Energy and Mines, Miscellaneous Report 92-4, p. 168–171. a summary of 1994–1996 results; gold in the Hurwitz Group, Hawk Hill–Griffin Lakes area, District of Keewatin, N.W.T.; Current Research, Part C, Geological Survey of Canada, Paper 90-1C, p. 219–230. Ennadai Lake area, District of Keewatin, and the shelf to foredeep transition in foreland Trans-Hudson Orogen; 1C, p. 143–155. Geological Survey, Saskatchewan Energy and Mines, Miscellaneous Report 97-4, p.Survey, Saskatchewan Energy and Mines, Miscellaneous Report 97-4, Geological 162–173. of Proterozoic magmatism; Canadian Journal Earth Sciences, v. 24, p. 1053–1063. p. 14–18. domains, Churchill Province, northern Manitoba, Canada; Canadian Journal of Earth Sciences, v. 24, p. 246–254. Sciences, v. 13, p. 355–364. Geological Survey of Canada, Paper 72-21, 29 p. Wollaston Domain; Saskatchewan Energy and Mines, Miscellaneous Report 95-4, p.Saskatchewan Energy and Mines, Miscellaneous Report 95-4, 49–60. Thorsteinson, and Baldock Batholiths, Churchill Province, Manitoba; Trans-Hudson Orogen of North America, J.F. Lewry and M.R. Stauffer (ed.), Geological Association of Canada, Special Paper 37, p. 201–214. Proterozoic Trans-Hudson Orogen of North America, (ed.) J.F. Lewry and M.R. Stauffer; Geological Association of Canada, Special Paper 37, p. 15–39. Hudson Orogen of North America, J.F. Lewry and M.R. Stauffer (ed.), Geological Association of Special PaperCanada, 37, p. 1-14. v. 68, p. 45–82. Z G G Zh Gh 1992: U-Pb Geochronology of some granitoids from the Peter Lake Domain: summary; a 1997: U-Pb geochronology of thermotectonic events in the Wollaston Lake area, Domain: 1990: infolding, and implications for basement-cover dome-and-basin sedimetation, Stratigraphy, 1989: belt, thrust-fold Sedimentology, structure, and economic geology of the Poorfish-Windy 1987: U-Pb zircon ages from the Lynn Lake and Rusty metavolcanic belts, Manitoba:ages two 1990: Proterozoic collisional tectonism in the Trans-Hudson Orogen, Saskatchewan; Geology, v. 18, 1988: ages of Archean and Proterozoic rocks in the Nejanilini Great Island Rubidium-strontium 1976:Earth Rb/Sr dating of rocks from the Wollaston Lake belt Saskatchewan; Candian Journal of 1973: Geology of the Nueltin Lake and Edehon (west half) map-areas, District Keewatin; 1995: Lithogeochemistry of volcanic rocks from the Lower Proterozoic Courtenay Lake formation, 1990: Trace- 1990: Subdivision of the Churchill Province and extent Trans-Hudson Orogen; 1990: The Trans-Hudson Orogen: extent, subdivision and problems; 1980: Thermotectonic evolution of the Churchill Province in northern Saskatchewan; Tectonophysics, N N Zh 0 O

50 Baldwin, D.A., Syme, E.C., Zwanzig, H.V., Gordon, T.M., Hunt, P.A. and Stevens, R.D. Bickford, M.E., Collerson, K.D., Lewery, J.F., Van Schmus, W.R. and Chiarenzelli, J.R. Bickford, M.E., Collerson, K.D., Lewery, J.F., Van Schmus, Clark, G.S. and Schledewitz, D.C.P. Cummings, G.L. and Scott, B.P. Eade, K.E. Fossenier, K., Delaney, G.D. and Watters, B.R. Halden, N.M., Clark, G.S., Corkery, M.T., Lenton, P.G. and Schledewitz, D.C.P. Hoffman, P.F. Lewry, J.F. and Collerson, K.D. Lewry, J.F. and Sibbald, T.I.I. Annesley, I.R., Madore, C. and Krogh, T.E. Annesley, I.R., Madore, C., Rupan, S. and Krogh, T. E. Aspler, L.B.and Bursey, T.L. Aspler, L.B., Bursey, T.L. and Miller, A.R. 000 96 66

N 00 O 000

O 66 0

’

0 50 000 ’ 65 0 96 60 ’ 0 O 45 59 30 15

Universal Transverse Mercator Projection Mercator Transverse Universal 15Zone North American Datum1983

54K

Paleozoic

94 Bay Juvenile Paleoproterozoic rocks

Parker Lake Shear Zone Great Island Churchill

Fergus River Shear Zone Fergus Reilly Lake Shear Zone

Hudson 60 GI RLSZ PLSZ

FRSZ 54L .

2 54E

m 54M ed rift

ray Ma 96 km by Hudson directed Ma may trending Ma (Van km and a mum age

floor rocks Block

Chipewyan

GI Ennadai up was also

up geological

Nunavut

Manitoba

64H

64I 64P This survey was age history. Gold ural control of the Hearne craton and . Ma; Bickford et al., trending shear zone Great Island Group - IslandGreat overlies Group metavolcanic rocks at and Pre- Great Island Great Pre- Group quartz diorite east of Great Island

Paleoproterozoic intrusions margin magmatic arc

98 100 lision structure), along its Hudsonian sedimentary and

central United States, through

64O

64G 64J ver metavolcanic rocks and the Hudson Orogen, was reported by trending shear zone in Seal River PART OF TRANS-HUDSON OROGEN

average uranium contents, delineated

0 Wathaman - Chipewyan Magmatic Arc Magmatic Chipewyan - Wathaman FRSZ

ppm uranium equivalents (eU), coincide 100

), based on geological mapping by the Hearne Hudson Orogen and were involved in the

Province of the of Province

et al., 1987), characteristically fluorite bearing craton Hearne Rae-

64F

Lynn Lake Domain Lake Lynn 64K 64N

Ma (Patterson and Heaman, 1991) possibly

Shear Zone Shear

Snowbird margin (?) successions, forming fold and thrust belts, Nunavut

with higher-than- Ensialic Zone Mobile uncertainParagneiss, age lphides hosted by Seal River metavolcanic rocks. In N.W.T. Archean, altered, abundant Paleoproterozoic intrusions

Manitoba

Saskatchewan 102

Ma (Patterson and Heaman, 1991), intrude the lower Ameto Hudson Orogen, the Cree Lake Ensialic Mobile Zone of

e RLSZ 64E

degree of reworking uncertain reworking of degree

64L o 64M

La Ronge - Southern Indian Domain Indian Southern - Ronge La C

a tectonites

concentrations occur in the Seal Ri L

broad regions PLSZ

omain and La Ronge belt in Saskatchewan Southern Indian, Lynn e t

year exploration program by Manitoba Mineral Resources Ltd., initiated e P

s of the Montgomery Group and Hurwitz Group, overlying Ameto

104

Rae

Shear Zone Shear

km downstream from Great Island (NTS 54L and M), indicates the presence of Group Wollaston

Province of the of Province

Bear River Bear

Rae- Hearne craton Hearne Rae- precious-metal Canada and ultimately to Greenland (Lewry Collerson, 1990). In Manitoba Shear Zone Shear

were analyzed for U, Zn, Cu, Pb, Ni, Co, Ag, Mn, Fe, Mo, As, Hg and loss-on-ignition. cratonic zone cratonic

LITHOTECTONIC ELEMENTS OF

Archean, undivided

Hurwitz Group Wollaston Group tectonites

Needle Falls Needle

Athabasca Basin Athabasca

Shear Zone Shear Grease River Grease rrane consisting of the Rottenstone Domain, Southern Indian Domain and La Ronge e deformation continued along the Needle Falls Shear Zone and mostly sheared boundary Ma on synkinematic tonalitic gneiss that postdates some phases of deformation [Lewry et al., 54M; Manitoba Industry, Economic Development and Mines, Manitoba Geological Survey,54M, NTS Bedrock Geology Compilation Map Series, scale 1: 250 000. Formation (Nunavut) range in age from 2400 to 2100 (Aspler and Bursey, 1990). sedimentation represent cratonic-basin of the Wollaston Group (Saskatchewan), with a minimum age 2100 The Courtenay Lake Formation (Annesley et al., 1997), unconformably overlies garnet-biotite gneiss (age uncertain). Wollaston Group calcsilicate rocks (Manitoba) overlie garnet-biotite gneiss (age uncertain). Pre-Hudsonian mafic igneous and volcanic rocks have a geochemistry that favours continental- setting. Mafic sills and flows, dated at 2094 +26/–17 Formation and underlying Kinga of the Hurwitz Group (Nunavut). Mafic pillowed and massive flows in the Courtenay Lake Formation (Saskatchewan) have a minimum age of 2100 Ma (Fossenier et al., 1995; Annesley 1997). This mafic igneous activity at ca. 2100 be related to opening of the Manikwan Sea (Aspler and Bursey, 1990; Patterson Heaman, 1991). Synorogenic magmatism, as early 1.91 Ga and related to the Trans- Baldwin et al. (1987) in felsic volcanic rocks at Lynn Lake. including overthrusting of foredeep deposits (?). Deformation and metamorphism occurred in the Rottenstone Domain (Saskatchewan; mini 1867 ±8 1987]). Accretion added a complex collage of Paleoproterozoic volcanic island-arc, back-arc to ocean- and intrusive rocks (Rottenstone D Lake and Leaf Rapids domains in Manitoba) to the Rae-Hearne craton, possibly via southeast- subduction (Bickford et al., 1990). occurred between 1865 and 1855 complex plutonic Wathaman-Chipewyan the of Emplacement Schmus and Schledewitz, 1986; Meyer et al., 1992), possibly as a continental- related to a northerly subduction flip. This magmatic arc lies between the Archean Rae- an accreted te and Lynn Lake greenstone belts. The magmatic arc effectively stitched together the craton terranes. Paleoproterozoic accreted-arc magmatic arc was deformed along the Needle Falls Shear Zone (an oblique col boundary with the Wollaston Domain and along shear zones at Peter Lake Complex (Reindeer Lake, Saskatchewan). At ca. 1820 to 1812 Ma, the Wollaston Group, underlying Archean basement and early-form Hudsonian intrusions were affected by peak thermal metamorphism (Annesley et al., 1997) that was synchronous with the age of peak metamorphism in internal juvenile zone Trans- Orogen. Ductile-brittl of the Peter Lake Complex (Ray and Wanless, 1980; Van Schmus et al., 1987). Folds tightened and ductile-brittle shearing occurred in the Wollaston Mudjatik domains. and east-trending ductile-brittle shear zones were superimposed on the east-Northeast-, north- Wathaman-Chipewyan magmatic arc, Seal River Domain and Nejanilini Domain. the of structures Postcollisional granite bodies (1753 +3/–2 Ma; Loveridge and with rapakivi texture high uranium background, occur most commonly in parts of the Hearne Province where negative gravity anomalies exceed –60 mGal (Schledewitz, 1986). The Kinga and Padlei formation Early arc-continent collision possibly occurred at 1888 to 1860 Ma (Bickford et al., 1990). and passive- Deformation occurred in cratonic-basin At 1855 to 1800 Ma (Stauffer and Lewry, 1993), the northwestern margin of Wathaman- rane of Archean basement and Paleoproterozoic sedimentary basins that constituted the foreland zone • • • • • • • • • collision, deformation and emplacement of nappe sheets (1830–1800 Continent-continent • to postcollisional deformation: Late- • • • • Economic geology The North Caribou Lake area was flown at a line spacing of 5gamma- km, using a high-sensitivity spectrometer, as part of the federal-provincial Uranium Reconnaissance Program (URP) carried out in 1975 and 1976 by the Geological Survey of Canada, with participation from Manitoba. The survey sediment sampling, with an approximate density of one sample per 13included concurrent lake-centre km samples Lake-sediment The URP, which was intended to define such zones of uranium enrichment in the Kasmere Lake map area (NTS 64N) and, to a lesser extent, Munroe Lake map area (NTS 64O). In the Caribou 54M), airborne radiometric uraniu and coincident potassium anomalies, with uranium greater than 2.8 with areas of Paleoproterozoic porphyritic monzogranite (unit Manitoba Mineral Resources Division subsequent to the release of URP survey. Ground follow- carried out by mining companies and the Geological Survey of Canada. This activity was summarized Schledewitz (1986). and Indications of base- unconformably overlying Great Island Group. Extensive exploration in the Seal River metavolcanic and igneous rocks on the Seal River, 66 volcanogenicsulphide–type mineralization. The Seal River metavolcanic rocks, forming a 5 massive 20 km domain, were the focus of a six- (EM) surveys and follow- in 1972–1973. The investigation included airborne electromagnetic mapping, ground EM, trenching and diamond-drilling. Gold mineralization in the Caribou River and adjacent map areas appears to have a multi- occurs in trace amounts volcanogenic massive su addition, a younger, structurally controlled phase of gold mineralization is associated with iron formation in both the Seal River metavolcanic rocks and overlying Great Island Group rocks. The struct younger gold deposits is suggested by localization of mineralization along an easterly- at the northwest corner of Great Island (NTS 64I), and by a northeasterly- metavolcanic rocks (NTS 54L and M). Regional tectonic synthesis Rocks of the Nejanilini Lake map area are part Trans- Paleoproterozoic tectonics and thermotectonism that dominated this orogen. Rocks of the area evolved as a ter Ray-Hearne craton. The Trans-Hudson Orogen extends for approximately 5000 km from the north- the Churchill Province in Saskatchewan, two major elements of the Trans- Archean Hearne Province and the juvenile Paleoproterozoic arc-related terranes, are separated by the Andean- Wathaman-Chipewyan continental magmatic arc. The latter has a minimum strike length of 900 type width of 15 to 150 km. Radiometric dating of pre-Hudsonian rocks Radiometric dating has allowed delineation of Archean to Paleoproterozoic pre- igneous rocks that were subsequently involved in several discrete tectonic events resulting from multistage subduction and collision processes. Pre-Hudsonian sedimentation: • Hudsonian collisional tectonics Incorporation of the entire Paleoproterozoic cover sequence, juvenile synorogenic volcanic and intrusive rocks, and the Archean ‘basement’ into Trans-HudsonOrogen: • • 1990): • Synoptic geology by D.C.P. Schledewitz Compilation by D.C.P. Schledewitz and D. Lindal Digital CAD drafting by M. McFarlane and B. Lenton GIS cartography by L. Chackowsky Suggested reference: Caribou NTS Development and Mines 2005: River, Economic Industry, Manitoba Published by: Manitoba Industry, Economic Development and Mines Manitoba Geological Survey, 2005 Disclaimer Every possible effort has been made to ensure that the information presented on this map is accurate. However, Manitoba Industry, Economic Development and Mines does not assume liability for any errors that may occur. References are forincluded users wishing to verify information. 0 0 0 0 0 0 O O O O O O ). 59 57 55 53 51 49 En Tn , ) and MARGINAL NOTES Zh Gp ) and garnet- on NTS 64P). Sr initial ratios 86 En W 0 O ss/migmatite 35 Ma (initial ratio 92 Sr/ ± 87 ) that intrudes the Seal

) to the north and east.

R G River

) and garnet-biotite gneiss 0

O Ontario H U D S O N Y A B Zh KILOMETRES 92 ), is of uncertain age despite

) that predates the Great Island

NORTHERN SUPERIOR

G River LAKE high temperature) metamorphism ), porphyritic granite (unit Tn

ZONE

s Granite- greenstone

Batholithic granite and granitoid gneiss Sedimentary gnei Trans- Hudson Orogen (Proterozoic- Archean) Superior Structural Province (Archean) Cenozoic Mesozoic Paleozoic G d o

fold.

1 G 0 50 100 150 200 250 River

Hayes

Lake Churchill b) make up the remainder of Nejanilini

on NTS 64I] or an interlayered quartzite- Gods P A L E O Z O I C Phanerozoic Precambrian Lithostructural belts & domains

K Lake River

KISSEYNEW ) indicates that Archean rocks of the Nejanilini River

18 Ma and 2777 +95/–66 Ma (Loveridge et al., Island ± 0 O UCHI extends into Nunavut, where it is considered to be extends into Nunavut, where it is consideredto

Tn BOUNDARY GODS RIVER 0 GREAT ISLAND

Nelson

Tn LAKE

ISLAND WABIGOON

) comprise massive and pillowed basalt andesite, WINNIPEG Winnipeg 96 Churchill BIRD RIVER V

River

RIVER

BERENS

Minnesota (Clark and Schledewitz, 1988). High

River ASSEAN LAKE ASSEAN

sillimanite, hypersthene+cordierite+sillimanite+garnet+biotite

NEJANILINI

PIKWITONEI

Nunavut

Seal

ENGLISH RIVER Red MOLSON LAKE MOLSON WINNIPEG Sr ratio of 0.7057 (Clark and Schledewitz, 1988). 86

Southern Sr/

Indian

MESOZOIC

87 SUPERIOR C River Lake I ) has a Rb-Sr whole-rock isochron age of 1795

WINNIPEG O

Thompson

LAKE Ma has been established for the Wollaston Group by dating an igneous

Gp Z

0 O O ), which occurs as remnants and inclusions in the hypersthene-bearing PRINCIPAL GEOLOGICAL DOMAINS

Sr ratio of 0.7150 for a quartz-feldspar porphyry (unit Sr ratio of 0.7150 for a quartz-feldspar E ), and an unconformably overlying succession of metasedimentary rocks (units N ). The mineral assemblage andalusite+chlorite+garnet+muscovite+biotite in ). The mineral assemblage andalusite+chlorite+garnet+muscovite+biotite LAKE ) in the Mudjatik Domain of Kasmere Lake map area (NTS 64N). The Kasba 800-223-5215 86 LYNN LAKE C H I P E W Y A N L

V Assiniboine 100 Q

North Dakota ), with local occurrence of pyritic meta-argillite and overlain by quartzite ), with local occurrence of pyritic meta-argillite A MANITOBA Tn

CENOZOIC Sr/

P P 0 -Hudson Orogen (Hoffman, 1990), have been termed collectively the ‘Cree Lake ), which shows varying degrees of alkali metasomatism and contains widely Brandon ) and foliated tonalite and granodiorite (unit SEAL RIVER O on NTS 64P]) to deposition of an immature metagreywacke (unit GI 87 comprises a lower succession of mainly volcanic and intrusive rocks, known as the

Lake on NTS 64P], dolomitic marble [unit GI Zh Zh Q

Cedar 100

). Clark and Schledewitz (1988) referred to this complex of Archean rocks (units R in the map area is dominated by Archean orthogneiss and foliated granitic rocks, with n

IF a

LAKE

N w vailable for free download at www.gov.mb.ca/iedm/mrd/

WOLLASTON e MUDJATIK FLIN FLON h WINNIPEGOSIS Paleoproterozoic metamorphic mineral assemblages produced during Hudsonian 42 Ma, with an initial A Copies of this map can be obtained from: Manitoba Industry, Economic Development and Mines Manitoba Geological Survey, Publication Sales 360–1395 Ellice Avenue Winnipeg MB R3G 3P2 Canada Phone: (204) 945-4154 Toll-free: 1- [email protected]: tc

Lynn Lake a ±

KISSEYNEW k

SOUTHERN INDIAN s

a The Pas M E S O Z O I C

Flin Flon S ) on the west side of outlier and porphyritic quartz diorite (unit Saskatchewan 3 interpreted to be an igneous crystallization age, was obtained from samples of mylonitic Ma, G ), included in the Great Island Group (Schledewitz, 1986). An unconformable contact is inferred ± P 0 0 0 0 0 0 O O O O O O 59 57 55 53 51 49 ) inclusions and enclaves of gneissic tonalite (unit ) inclusions and enclaves of gneissic tonalite 41 Ma and an initial x x occurring on NTS 64P) the Nejanilini granulite massif. A sample of monzocharnockite yielded a as ± N Nejanilini Domain Great Island Domain T v and GI Q Domain formed the country rock prior to emplacement of these Paleoproterozoic intrusions. The Caribou Lake porphyritic quartz monzonite (unit 0.7084)). This age is considered to be a minimum for crystallization, because Rb-Sr ages are consistently ages zircon when compared to U-Pb lower by 2–3% (unit Domain in the Caribou Lake map area. The presence of monzocharnockite (unit lithological similarity to lower parts of the Paleoproterozoic Wollaston Group. This is because it locally contains mineral assemblages (cordierite granulite-facies granite gneiss (unit lesser amounts of well-foliated biotite-magnetite phyllite sequence [unit GI and Rb-Sr age of 2577 and hypersthene+garnet+biotite) that are more compatible with their granulite-facies Archean host than the and hypersthene+garnet+biotite) that are more compatible with their granulite-facies middle grade typical of Paleoproterozoic thermotectonism. In the absence dates, to upper amphibolite-facies the age of these enclaves metasedimentary rocks remains uncertain (Eade, 1973; Weber et al., 1975b; Cummings and Scott,1976). (unit granite Large bodies of Paleoproterozoic medium- to coarse-grained grey gneiss, which has yielded U-Pb zircon ages of 3274 yielded grey gneiss, which has monzocharnockite (unit 1988), is likely of mixed origin. Metasedimentary gneiss (unit This unit forms clusters of low, flat outcrops that are typically light grey to buff on weathered surface and greyish The central part of the Caribou River map area comprises foliated grey tonalitic to granodioritic gneiss (unit The central part of the Caribou River map area comprises foliated grey tonalitic Regional setting The Caribou River map sheet (NTS 54M), which lies on the south flank of Hearne Province Rae- Hearne Archean craton, comprises continental crust and Paleoproterozoic cover strata that have together been affected by varying degrees of Paleoproterozoic plutonism and thermotectonism. These rocks, which are part of the Trans Lithological units The Nejanilini Domain occupies most of the map sheet. It comprises mainly foliated Archean granitic and granitoid rocks. A 20 km wide zone at the south margin of map area is underlain by metasedimentary and metavolcanic rocks of the Great Island Domain. Both Nejanilini and domains are intruded by Paleoproterozoic plutons. Rocks of both the Nejanilini and Great Island domains contain middle to upper amphibolite-facies thermotectonism. The enclaves of migmatized supracrustal rocks. The principal rock type is a foliated, hypersthene-bearing monzocharnockite (unit white to pink on fresh surface. West of the map area, unit with the Great Island sedimentary sequence in adjacent Nejanilini Lake map area (Manitoba Industry, Trade and Mines, 2002). Seal the radiometric ages, although far from definitive, indicate a possiblefor Rubidium-strontium age Archean River volcanic rocks and a Paleoproterozoic age for of the Great Island Group. A minimum 2052 Archean Ennadai Lake metavolcanic belt. (silicate sedimentation platform The Great Island Group rocks display an abrupt change from cratonic-basinand iron formation [unit GI The timing of this change is uncertain but may coincide with continental rifting recorded in the Wollaston Group and the Hurwitz Group. The rifting event in Group is constrained by U-Pb zircon baddeleyite ages of 2094 +26/–17 Ma (Patterson and Heaman, 1991) from gabbro sills in the lower to middle Ameto Formation of the Hurwitz Group. This defines a minimum depositional age ca. 2100 Ma for the lower to middle Ameto Formation. The and post-Ameto formations define a change from cratonic-basin sedimentation in the underlying Padlei and Kinga formations to a period of crustal subsidence tectonic destabilization in the Hurwitz Group. A minimum geological age of 2100 scattered, discontinuous inclusions of hypersthene-bearing, intermediate to mafic gneiss (unit biotite migmatite (unit intrusion cutting rocks of the Courtenay Lake Formation Wollaston Group (Annesley et al., 1992). The date of 2076 quartzofeldspathic gneiss in the rocks of Courtenay Lake Formation. Formation conglomerate, arkose and quartzite are interlayered with mafic volcanic rocks characterized by within-plate lithogeochemistry, thus favouring emplacement in a continental-rift setting (Fossenier et al., 1995; MacNeil al., 1997). Relationships between the Hurwitz Group, Great Island Wollaston Group and Seal River metavolcanic rocks Between 2400 and 2100 Ma, Paleoproterozoic metasedimentary rocks and derived paragneiss of the Hurwitz Group, Great Island Group and Wollaston were deposited unconformably on Archean basement rocks of the Hearne Province. The Great Island Group (2100 Ma; Clark and Schledewitz, 1988) is interpreted to be the remnant of a cratonic basin, similar to one occupied by metasedimentary rocks the coeval Hurwitz Group in Nunavut (2400–2100 Ma; Patterson and Heaman, 1991). The Hurwitz Group unconformably overlies the equivalent to the Archean Kasba grey gneiss (Eade, 1973; Loveridge et al., 1988). It is also likely the grey tonalitic gneiss (unit Ensialic Mobile Zone' by Lewry et al. (1978), Lewry and Sibbald (1980) and Lewry and Collerson (1990). There (1990). Collerson and Ensialic Mobile Zone' by Lewry et al. (1978), and Sibbald (1980) are several local domains relatively unaffected by Hudsonian overprint. One of these, the Ennadai Block (Lewry et al., 1985), outcrops in the extreme northwest corner of Manitoba and extends north Caribou River map sheet into Nunavut. The Cree Lake Ensialic Mobile Zone, which dominates the map area, has been regionally subdivided into six geological domains in Saskatchewan and Manitoba: the Mudjatik, Peter Lake (present only Saskatchewan), Wollaston, Seal River, Great Island and Nejanilini domains. The domains are defined by their cover rocks, the proportion or absence of basement rocks, and their dominant structural trends. Two these domains, the Nejanilini and Great Island, occur in the Caribou River map area. They are separated from accreted juvenile Paleoproterozoic terranes to the south by Wathaman-Chipewyan batholithic belt, remnant of a continental magmatic arc. are characteristic of plutons in the Cree Lake zone. The Paleoproterozoic intrusions separate Nejanilini Massif from the Great Island Domain. The GI Seal River volcanic rocks (unit Grade of metamorphism in the Great Island Domain is defined by mineralogy interlayered phyllite and quartz metasiltstone (unit GI phyllitic rocks of the basal Great Island Group at (NTS 64I) indicates lower to middle amphibolite- (low pressure and facies metamorphic conditions. Middle amphibolite-facies is defined by the mineral assemblage muscovite+cordierite+sillimanite+biotite, which occurs in outliers of Great Island Group 100 km west of Great Island at Tadoule Lake (NTS 64J). River metavolcanic rocks (NTS 64I) constrains the age of these volcanic to Paleoproterozoic or older. In the Caribou River map sheet (NTS 54M), metavolcanic rocks form a narrow northeast-trending enclave, along porphyritic quartz diorite (unit the lower Seal River, within a granodiorite to between these rocks because intrusive contacts in the Seal River volcanic are truncated at their contact Group sedimentary rocks. The metavolcanic rocks (unit interlayered tuffaceous rocks, lapilli tuff, siliceous sedimentary rocks and rhyolite to rhyodacite, all intruded by porphyry and gabbro. stocks of quartz-feldspar Grey-green phyllite (unit GI Primary layering in the rocks of Great Island Group defines moderate closure folds about upright east- striking axial surfaces and moderate east-plunging axes. Available information suggests the structure to be F refolded and faulted, easterly-trending north end of a dumbbell-shaped, interlayered garnetiferous, pale green phyllite, outcrops as an outlier of the Great Island Group in Caribou River map area. The grey-green phyllite is in contact with garnetiferous biotite metatexite and granodioritic diatexite (unit