Towards a new stratigraphy of the Bird River Belt. H.P. Gilbert (MGS)

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1 Towards a new stratigraphy of the Bird River Belt H.P. Gilbert (MGS)

2 Bird River Belt projects initiated in Paul Gilbert (MGS) Regional mapping (1: scale) with focus on stratigraphy and geochemistry of supracrustal rocks. 2. Manuel Duguet (post doctoral student, Univ. of Waterloo) Regional mapping (1: : scale) with focus on structural geology and tectonic history. 3. Paul Kremer (MSc graduate student, Univ. of Waterloo) Geological mapping (1: scale) of Bernic area with focus on the setting of granitic pegmatite intrusions. 4. Caroline Mealin (MSc graduate student, Univ. of Waterloo) Detailed mapping of mafic-ultramafic Bird River Sill with focus on PGE mineralization potential.

3 Bird River Belt projects rationale Area last mapped over 25 years ago Previous mapping known to be inconsistent Since the previous mapping, advances in the geological sciences and new techniques (geochemistry and geochronology) now provide the opportunity to gain significant advances in our understanding of the geology of the area Provide support for current active exploration

4 Road map 1. Setting of Neoarchean Bird River greenstone belt 2. Geological overview 3. Results of mapping ~ Geochemistry Stratigraphy 4. Summary

5 Geological Domains in southwest Superior Province Berens River Uchi Bird River Belt English River Winnipeg Bird River BRB Manitoba Ontario Paleozoic Winnipeg River WINNIPEG Wabigoon Mesozoic 0 40 kilometres Canada United States of the Woods

6 Geological overview

7 mN. Bird River Belt volcanic components mE. HJS Lac du Bonnet Batholith Maskwa Batholith PMAP Bernic 0 10 kilometres Shatford Rush Birse Bird Osis BLS BRLS Obrien Birse pluton Greer Winnipeg River Tulabi Flanders Ryerson Marijane pluton Eaglenest The Bird River Belt consists mainly of an volcanosedimentary arc-type assemblage (2740 Ma) in two tectonostratigraphic components ~ a south-facing calc-alkaline north panel and a north-facing tholeiitic south panel. Older (> 2745 Ma) MORB-type volcanic rocks (Lamprey Falls Formation) occur along the north and south margins of the belt mE. Manitoba Ontario mN. Late intrusive rocks Granite, (Lac du Bonnet batholith, 2660 ±3 Ma) Sedimentary rocks FLANDERS LAKE FORMATION (2697 ±18 Ma) Arenite, polymictic conglomerate Fault, inferred BOOSTER LAKE FORMATION (2712 ±17 Ma) Greywacke-siltstone turbidite Unconformity, inferred Intrusive rocks Granodiorite, tonalite gabbro, quartzfeldspar porphyry (2725 ±6 Ma ; 2729 ±9 Ma) Metavolcanic and metasedimentary rocks arc assemblage (2740 ±4 Ma) Mafic to felsic volcanic rocks; turbidite, chert, iron-formation, conglomerate; derived gneiss and schist Intrusive rocks BIRD RIVER SILL (2745 ±5 Ma) Dunite, peridotite, picrite, anorthosite and gabbro Fault, inferred MORB-type basalt and metasedimentary rocks LAMPREY FALLS FORMATION B lt l t db i

8 BRB postvolcanic sedimentary rocks Maskwa Batholith BLS Bird Tulabi mE mN. Flanders Formation (2697 ± 18 Ma) HJS PMAP Bernic Rush Birse Osis BRLS Obrien Flanders Marijane pluton Formation (2712 ± 17 Ma) mN. Lac du Bonnet Batholith 0 10 kilometres mE. Archean Intrusive rocks Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario New detrital zircon data indicate these two formations postdate the volcanism by approx. 30 m.y.

9 Maskwa-Dumbarton BRB economic geology Lamprey Falls Fm Bird River Sill TANCO (Cabot Corp) HJS Maskwa Batholith PMAP Bernic Rush Bird Osis BLS BRLS Tulabi Flanders Marijane pluton mE mN. A r c Bird River Belt is known for the TANCO Mine (Cs and Ta), Maskwa-Dumbarton Mine (Cu-Ni) and PGE potential of the Bird River Sill. Additional exploration targets include (1) arc-type rocks (2) Lamprey Falls Fm at BRB north flank (Cu, Zn, Ni and PGE in gabbro) and (3) Lamprey Falls Fm at Winnipeg River (iron formation with basemetal mineralization) mN. Lac du Bonnet Batholith 0 10 kilometres mE. Archean Intrusive rocks Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Lamprey Falls Fm Greywacke, siltstone (Eaglenest Formation) Birse Obrien Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

10 Mineralization in iron formation within Lamprey Falls basalt, Winnipeg River area

11 Bird River Belt Geochemistry

12 Bird River Belt north and south panels BRB north panel Maskwa Batholith Bird BLS Tulabi mE mN. Formation HJS PMAP Bernic Rush Birse Osis BRLS Obrien Flanders Marijane pluton BRB south panel mN. Lac du Bonnet Batholith 0 10 kilometres mE. Archean Intrusive rocks Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

13 Bird River greenstone belt east part HJS Maskwa Batholith PMAP Bernic Rush Bird Osis BLS BRLS Tulabi Flanders Marijane pluton mE mN. Birse section Birse Obrien mN. Lac du Bonnet Batholith 0 10 kilometres mE. Archean Intrusive rocks Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

14 Bird River Belt south panel - Birse section Maskwa Batholith Bird BLS Tulabi mE mN. HJS PMAP Bernic Rush Birse Osis BRLS Obrien Flanders Marijane pluton Birse section mN mE. Shatford Lac du Bonnet Batholith 0 10 kilometres Birse pluton Winnipeg River Greer Rock/N-MORB Ryerson Eaglenest Manitoba Ontario Birse Section North part Central part South part.1 Th Nb La Ce Nd Sm Zr Hf Eu Ti Gd Dy Y Er Yb Lu

15 MORB-type basalt localities in the Bird River Belt Lamprey Falls Formation (BRB North Flank) HJS Maskwa Batholith PMAP Bernic Rush Bird Osis BLS BRLS Tulabi Flanders Marijane pluton mE mN. Lamprey Falls Formation (Winnipeg River) mN mE. Lac du Bonnet Batholith 0 10 kilometres Shatford Birse Obrien Birse pluton Winnipeg River Greer Ryerson Eaglenest Manitoba Ontario 100 Lamprey Falls Formation (BRB North Flank as well as Winnipeg River) Rock/N-MORB Birse section south - MORB type basalt Lamprey Falls Formation (BRB north flank and Winnipeg River suites) Th Nb La Ce Nd Sm Zr Hf Eu Ti Gd Dy Y Er Yb Lu Birse section section south part (= south Lamprey part Falls Fm.?)

16 Arc-type volcanic rocks Rock/NMORB 100 Stern et al., 1995 (FFB Ocean Floor paper) Maskwa Batholith Bird BLS Tulabi mE mN. BRB north panel arc-type rocks HJS PMAP Bernic Rush Birse Osis BRLS Obrien Flanders Marijane pluton BRB North panel mN mE. Shatford Lac du Bonnet Batholith 0 10 kilometres Birse pluton Winnipeg River Greer Ryerson Eaglenest Manitoba Ontario.1 Th Nb La Ce Nd Sm Zr Hf Eu Ti Gd Dy Y Er Yb Lu Rock/N-MORB Birse Section North part Central part South part Th Nb La Ce Nd Sm Zr Hf Eu Ti Gd Dy Y Er Yb Lu Birse section ~ north central Rock/NMORB Stern et al., 1995 (FFB Ocean Floor paper) Birse section north Birse section central Th Nb La Ce Nd Sm Zr Hf Eu Ti Gd Dy Y Er Yb Lu

17 BRB arc-type volcanic rocks north and south panels FeO+Fe O +TiO BRB north panel arc-type rocks BRB south panel arc-type rocks Tholeiitic FeO* BRB north panel arc-type rocks BRB south panel arc-type rocks Komatiitic Calc-Alkalic Al O 2 3 MgO Jensen cation diagram Tholeiitic Calc-Alkaline Alk AFM MgO

18 Bird River greenstone belt all volcanic rocks D Zr/117 A B BRB north panel arc BRB south panel arc Birse south - MORB type basalt Lamprey Falls Formation (total) A = N-MORB B = E-MORB C = OIB (Rift) D = Arc-basalts C Th Nb/16

19 Bird River Belt Stratigraphy 1. MORB-type volcanic rocks 2. Arc-type assemblage 3. Formation

20 Bird River Belt Stratigraphy 1. MORB-type volcanic rocks 2. Arc-type assemblage 3. Formation

MORB-type basalt localities in the Bird River Belt Lamprey Falls Fm

Obrien Birse section south part 5582500mN. 740000mE.

21 MORB-type basalt localities in the Bird River Belt Lamprey Falls Fm (BRB north flank) Maskwa Batholith Bird BLS Tulabi mE mN. HJS PMAP Bernic Rush Osis BRLS Flanders Marijane pluton Birse Obrien Birse section south part mN mE. Lac du Bonnet Batholith 0 10 kilometres Shatford Birse pluton Winnipeg River Lamprey Falls Formation (Winnipeg River) Greer Ryerson Eaglenest Manitoba Ontario

22 Bird River Belt Stratigraphy 1. MORB-type volcanic rocks 2. Arc-type assemblage 3. Formation

23 Bird River Belt north and south panels BRB north panel Maskwa Batholith Bird BLS Tulabi mE mN. Formation HJS PMAP Bernic Rush Birse Osis BRLS Obrien Flanders Marijane pluton BRB south panel mN. Lac du Bonnet Batholith 0 10 kilometres mE. Archean Intrusive rocks Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

24 Bird River greenstone belt - arc assemblage sections Highway Junction section Bird section HJS Maskwa Batholith PMAP Bernic Rush Bird Osis BLS BRLS Tulabi Flanders Marijane pluton mE mN. Birse section Birse Obrien mN. Lac du Bonnet Batholith 0 10 kilometres mE. Archean Intrusive rocks Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

BRB south panel (Birse section) North north (arc) Inferred fault ( F) Formation NORTH F Greywacke-siltstone turbidite Felsic tuff, locally redeposited by turbidity currents Aphyric basalt flow/sill

arc-type sequence CENTRAL F F Garnetiferous amphibolite, mafic schist, mineralized with pyrite Greywacke-siltstone + - cordierite ( Formation fault slice) Felsic tuff, wacke Rhyolite breccia,

25 BRB south panel (Birse section) North north (arc) Inferred fault ( F) Formation NORTH F Greywacke-siltstone turbidite Felsic tuff, locally redeposited by turbidity currents Aphyric basalt flow/sill Pegmatite Felsic tuff Aphyric basalt, derived laminated gneiss Greywacke-siltstone turbidite ( Formation fault slice) Pegmatite Aphyric basalt, related mafic gneiss central (arc) Volcano-sedimentary arc-type sequence CENTRAL F F Garnetiferous amphibolite, mafic schist, mineralized with pyrite Greywacke-siltstone + - cordierite ( Formation fault slice) Felsic tuff, wacke Rhyolite breccia, monolithic Rhyolite, massive Aphyric basalt, pillowed basalt Rhyolite breccia, monolithic Pegmatite Garnet-hornblende gneiss, basalt-derived Rhyolite, massive Pegmatite Rhyolite breccia, monolithic Altered felsic volcanic rocks, extensive hornblende blastesis Aphyric basalt Rhyolite, related breccia; felsic tuff Gabbro, medium-grained to very coarse grained, diabase Aphyric basalt Felsic volcanic breccia, monolithic Altered felsic volcanic rocks, extensive hornblende blastesis 600 Felsic volcanic breccia, heterolithic 500 south (MORB) metres SOUTH Birse pluton F F South Diabase Felsic volcanic breccia, heterolithic; locally reworked by mass flows Mafic schist and gneiss, basalt-derived Felsic volcanic rocks Aphyric basalt, pillowed basalt (up to 500 m thick)-morb type Tonalite, granodiorite, equigranular to porphyritic Base-metal mineralization

26 Bird River greenstone belt east part Highway Junction section Maskwa Batholith Bird BLS Tulabi mE mN. HJS PMAP Bernic Rush Osis BRLS Flanders Marijane pluton Birse Obrien mN. Lac du Bonnet Batholith mE. Archean Intrusive rocks kilometres Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

BRB north panel - Highway Junction section South Formation Inferred fault No exposure Greywacke-siltstone turbidite Dacite, massive 5W Synsedimentary folds in laminated chert 15W Felsic

volcanic breccia and tuff, reworked Felsic tuff (possible ash-flow origin) Rhyolite breccia ( + - chert clasts) 11 W Massive to fragmental rhyolite 10W Aphyric basalt, locally

1W 5W 4W Aphyric basalt, locally amygdaloidal Polymictic conglomerate Greywacke-siltstone turbidite Chert Aphyric basalt Greywacke-siltstone turbidite Heterolithic volcanic breccia, mafic

27 BRB north panel - Highway Junction section South Formation Inferred fault No exposure Greywacke-siltstone turbidite Dacite, massive 5W Synsedimentary folds in laminated chert 15W Felsic volcanic breccia, tuff 1500 metres 1000 Volcanosedimentary arc-type sequence No exposure No exposure 14W 13W 12W Intermediate to felsic tuff (possible ash-flow origin) Heterolithic volcanic breccia and tuff, reworked Felsic tuff (possible ash-flow origin) Rhyolite breccia ( + - chert clasts) 11 W Massive to fragmental rhyolite 10W Aphyric basalt, locally quartz-amygdaloidal 3W Scoured chert laminae and rip-ups in feldspathic greywacke turbidite 9W Felsic volcanic breccia, reworked W Bird River Sill no exposure North 8W 7W 6W 3W 2W 1W 5W 4W Aphyric basalt, locally amygdaloidal Polymictic conglomerate Greywacke-siltstone turbidite Chert Aphyric basalt Greywacke-siltstone turbidite Heterolithic volcanic breccia, mafic tuff Felsic and intermediate tuff, lapilli tuff Dunite, peridotite, picrite, anorthosite & gabbro 5W 1W 1W Laminated greenweathering tuff and overlying lapilli tuff mass-flow deposit 1W Stratigraphic unit numbers

BRB north panel - Highway Junction section Formation Inferred fault South No exposure Greywacke-siltstone turbidite Dacite, massive 7W Polymictic conglomerate with basalt and

ash-flow origin) Heterolithic volcanic breccia and tuff, reworked Felsic tuff (possible ash-flow origin) Rhyolite breccia ( + - chert clasts) 11 W Massive to fragmental rhyolite

volcanic breccia, reworked Aphyric basalt, locally amygdaloidal Polymictic conglomerate Greywacke-siltstone turbidite Chert Aphyric basalt Greywacke-siltstone turbidite

28 BRB north panel - Highway Junction section Formation Inferred fault South No exposure Greywacke-siltstone turbidite Dacite, massive 7W Polymictic conglomerate with basalt and gabbro fragments 15W Felsic volcanic breccia, tuff 1500 metres 1000 Volcanosedimentary arc-type sequence No exposure No exposure 14W 13W 12W Intermediate to felsic tuff (possible ash-flow origin) Heterolithic volcanic breccia and tuff, reworked Felsic tuff (possible ash-flow origin) Rhyolite breccia ( + - chert clasts) 11 W Massive to fragmental rhyolite 10W Aphyric basalt, locally quartz-amygdaloidal 7W Bedded chert boulder in polymictic conglomerate Bird River Sill no exposure North 9W 8W 7W 6W 3W 2W 1W 5W 4W Felsic volcanic breccia, reworked Aphyric basalt, locally amygdaloidal Polymictic conglomerate Greywacke-siltstone turbidite Chert Aphyric basalt Greywacke-siltstone turbidite Heterolithic volcanic breccia, mafic tuff Felsic and intermediate tuff, lapilli tuff Dunite, peridotite, picrite, anorthosite & gabbro 7W 5W 5W Bedded chert within 25 m thick member 1W Stratigraphic unit numbers

BRB north panel - Highway Junction section South Formation Inferred fault No exposure Greywacke-siltstone turbidite Dacite, massive 14W Chert rip-up in reworked lapilli tuff 15W

Heterolithic volcanic breccia and tuff, reworked Felsic tuff (possible ash-flow origin) Rhyolite breccia ( + - chert clasts) 11 W Massive to fragmental rhyolite 10W Aphyric basalt,

$breccia, mafic tuff Felsic and intermediate tuff, lapilli tuff Dunite, peridotite, picrite, anorthosite & gabbro 11W Thermal contraction fractures in massive rhyolite 1W$

29 BRB north panel - Highway Junction section South Formation Inferred fault No exposure Greywacke-siltstone turbidite Dacite, massive 14W Chert rip-up in reworked lapilli tuff 15W Felsic volcanic breccia, tuff 1500 metres 1000 Volcanosedimentary arc-type sequence No exposure No exposure 14W 13W 12W Intermediate to felsic tuff (possible ash-flow origin) Heterolithic volcanic breccia and tuff, reworked Felsic tuff (possible ash-flow origin) Rhyolite breccia ( + - chert clasts) 11 W Massive to fragmental rhyolite 10W Aphyric basalt, locally quartz-amygdaloidal 14W 13W 11W 13W Felsic clasts in tuff of possible ash-flow origin 9W Felsic volcanic breccia, reworked 8W Aphyric basalt, locally amygdaloidal Bird River Sill no exposure North 7W 6W 3W 2W 1W 5W 4W Polymictic conglomerate Greywacke-siltstone turbidite Chert Aphyric basalt Greywacke-siltstone turbidite Heterolithic volcanic breccia, mafic tuff Felsic and intermediate tuff, lapilli tuff Dunite, peridotite, picrite, anorthosite & gabbro 11W Thermal contraction fractures in massive rhyolite 1W Stratigraphic unit numbers

30 Bird River greenstone belt east part Bird section Maskwa Batholith Bird BLS Tulabi mE mN. HJS PMAP Bernic Rush Osis BRLS Flanders Marijane pluton Birse Obrien mN. Lac du Bonnet Batholith mE. Archean Intrusive rocks kilometres Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

BRB north panel - Bird section Southwest Bird area South Bird section 3E Pillow basalt weathers out in spires, due carbonatized domains Greywacke-siltstone turbidite

Inferred fault North 5E 6E 5E 4E 3E 1E 2E 1E Mylonite (rhyolite-derived) Rhyolite, massive to fragmental; subordinate felsic tuff, porphyry and garnet gneiss derived

variously altered ( + - garnet) Greywacke-siltstone (turbidite) 650 m thick Rhyolite, massive to fragmental Greywacke-siltstone, rare grit (turbidite) Tonalite,

31 BRB north panel - Bird section Southwest Bird area South Bird section 3E Pillow basalt weathers out in spires, due carbonatized domains Greywacke-siltstone turbidite metres Greywacke-siltstone turbidite Heterolithic volcanic breecia 8E 7E South North Formation Volcanosedimentary arc-type sequence Maskwa Batholith Inferred fault North 5E 6E 5E 4E 3E 1E 2E 1E Mylonite (rhyolite-derived) Rhyolite, massive to fragmental; subordinate felsic tuff, porphyry and garnet gneiss derived from altered rhyolite Oxide-facies iron formation Oxide-facies iron formation, mafic gneiss, corderite-garnet-bearing siltstone Aphyric basalt, pillowed basalt, variously altered ( + - garnet) Greywacke-siltstone (turbidite) 650 m thick Rhyolite, massive to fragmental Greywacke-siltstone, rare grit (turbidite) Tonalite, granodiorite 3E 2E 1E 2E Rhyolite breccia of autoclastic origin Base-metal mineralization 1E Stratigraphic unit numbers 1E Quartz grit channel deposit within turbidite sequence

BRB north panel - Bird section Southwest Bird area South Bird section Greywacke-siltstone turbidite metres 1500 1000 500 0 Greywacke-siltstone turbidite Heterolithic

Rhyolite, massive to fragmental; subordinate felsic tuff, porphyry and garnet gneiss derived from altered rhyolite Oxide-facies iron formation Oxide-facies iron formation,

massive to fragmental Greywacke-siltstone, rare grit (turbidite) Tonalite, granodiorite 5E, 6E 4E 6E Layered chert and magnetiferous siltstone Base-metal mineralization 1E

32 BRB north panel - Bird section Southwest Bird area South Bird section Greywacke-siltstone turbidite metres Greywacke-siltstone turbidite Heterolithic volcanic breecia 8E 7E South North Formation Volcanosedimentary arc-type sequence Maskwa Batholith Inferred fault North 5E 6E 5E 4E 3E 1E 2E 1E Mylonite (rhyolite-derived) Rhyolite, massive to fragmental; subordinate felsic tuff, porphyry and garnet gneiss derived from altered rhyolite Oxide-facies iron formation Oxide-facies iron formation, mafic gneiss, corderite-garnet-bearing siltstone Aphyric basalt, pillowed basalt, variously altered ( + - garnet) Greywacke-siltstone (turbidite) 650 m thick Rhyolite, massive to fragmental Greywacke-siltstone, rare grit (turbidite) Tonalite, granodiorite 5E, 6E 4E 6E Layered chert and magnetiferous siltstone Base-metal mineralization 1E Stratigraphic unit numbers 4E Garnet and oval cordierite porphyroblasts in meta-siltstone (associated with iron formation) 5E Mylonitic rhyolite close to the faulted contact with Formation

BRB north panel southwest Bird area Southwest Bird area South Bird section Greywacke-siltstone turbidite metres 1500 1000 500 0 Greywacke-siltstone turbidite

Mylonite (rhyolite-derived) Rhyolite, massive to fragmental; subordinate felsic tuff, porphyry and garnet gneiss derived from altered rhyolite Oxide-facies iron

Greywacke-siltstone (turbidite) 650 m thick Rhyolite, massive to fragmental Greywacke-siltstone, rare grit (turbidite) Tonalite, granodiorite Base-metal mineralization

33 BRB north panel southwest Bird area Southwest Bird area South Bird section Greywacke-siltstone turbidite metres Greywacke-siltstone turbidite Heterolithic volcanic breecia 7E 8E 7E South North Formation Volcanosedimentary arc-type sequence Maskwa Batholith Inferred fault North 5E 6E 5E 4E 3E 1E 2E 1E Mylonite (rhyolite-derived) Rhyolite, massive to fragmental; subordinate felsic tuff, porphyry and garnet gneiss derived from altered rhyolite Oxide-facies iron formation Oxide-facies iron formation, mafic gneiss, corderite-garnet-bearing siltstone Aphyric basalt, pillowed basalt, variously altered ( + - garnet) Greywacke-siltstone (turbidite) 650 m thick Rhyolite, massive to fragmental Greywacke-siltstone, rare grit (turbidite) Tonalite, granodiorite Base-metal mineralization 7E Dark blue cordierite porphyroblasts in volcanic breccia matrix 1E Stratigraphic unit numbers 7E Rhyolite boulder in heterolithic mass flow deposit 7E Angular mafic and felsic fragments in volcanic breccia

34 Bird River Belt Stratigraphy 1. MORB-type volcanic rocks 2. Arc-type assemblage 3. Formation

35 Bird River greenstone belt east part Maskwa Batholith Bird BLS Tulabi mE mN. HJS PMAP Bernic Rush Osis BRLS Flanders Marijane pluton Formation Birse Obrien mN. Lac du Bonnet Batholith 0 10 kilometres mE. Archean Intrusive rocks Pegmatitic granite Granite, granodiorite, tonalite Shatford Tonalite, orthogneiss (Winnipeg River Domain) Dunite, anorthosite, gabbro (Bird River Sill) Sedimentary rocks Arenite, conglomerate (Flanders Formation) Greywacke, siltstone ( Formation) Greywacke, siltstone (Eaglenest Formation) Birse pluton Winnipeg River Greer Ryerson Arc-type volcanic and sedimentary rocks Bird River Belt, north panel Bird River Belt, south panel MORB-type mafic volcanic rocks Eaglenest Lamprey Falls Formation in Bird River Belt north panel Lamprey Falls Formation in Bird River Belt south panel Lamprey Falls Formation in the Winnipeg River area Geological contact Fault (inferred) HJS Highway Junction section BLS Bird section BRLS Birse section Manitoba Ontario

36 Flame structure in Fm. turbidite Graded bedding in Fm. turbidite

37 Bedding-foliation discordance and cordierite porphyroblasts in Fm. turbidite

38 Summary Neoarchean Bird River Belt consists of an arc-type calc-alkaline north panel (> 2740 ± 4 Ma) and tholeiitic south panel. Older (> 2745 Ma) MORB-type volcanic rocks (Lamprey Falls Formation) occur along the north and south margins of the belt The arc-type panels are separated by infaulted Formation turbidites that extend through the centre of the belt. Flanders Formation fluvial-alluvial rocks overlie the arc-type assemblage at east end of the belt. New data indicate an age of 2697 ± 18 Ma for the Flanders Formation and 2712 ± 17 Ma for Formation, indicating these formations postdate the volcanism by approximately 30 m.y. Bird River Belt is known primarily for TANCO Mine (Cs and Ta), Maskwa- Dumbarton Mine (Cu-Zn) and the PGE potential of the Bird River Sill. Additional basemetal and Au exploration targets exist within arc-type volcanic rocks and iron formation in the Bird River Belt. North of the arc assemblage, base-metal and PGE mineralization occurs in gabbros in the Lamprey Falls Formation; equivalent rocks at the Winnipeg River contain mineralized oxide-facies iron formation.

40 Please visit posters T7 to T10 for more information about the Bird area

Re-assessment of Bird River greenstone belt stratigraphy. Paul Gilbert Manitoba Geological Survey

Re-assessment of Bird River greenstone belt stratigraphy Paul Gilbert Manitoba Geological Survey Location of Bird River Belt Bird River Belt Winnipeg Bird River Belt projects initiated in 2005 Paul Gilbert