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Bird River greenstone belt in Manitoba – Neoarchean arc magmatism in the western Superior Province Paul Gilbert Manitoba Geological Survey

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Bird River greenstone belt in Manitoba – Neoarcheanarc magmatism in the western Superior Province

Paul GilbertManitoba Geological Survey

Location of Bird River Belt

Bird River BeltBird River Belt

Bird River BeltBird River Belt

WinnipegWinnipeg

Location of Bird River Belt in Manitoba

Geological Domains in southwest Superior Province

0 40

kilometres

Man

itoba

Ont

ario

Canada United States

Berens River

UchiEnglish River

Bird River

Winnipeg River

Wabigoon

Mesozoic

Paleozoic

WINNIPEG

BRB

Lake

Win

nipe

g

Lakeof the

Woods

97 06’0

51 17’0

49 00’0

95 11’0

Bird River Belt

English River Domain

Winnipeg River Domain

Winnipeg

Bird River Belt extent

BIRDRIVER

SEPARATION LAKE

MANITOBA

ONTARIO… Neoarchean Bird Rive Belt (150 km Manitoba-Ontario)

contains

TANCO Mine ~75% world Cs; also Ta

Bird River Sill ~PGE, Cr (Ni, Cu, Zn)

Outline of presentation

1. Geological overview Bird River Belt

2. Geochemical – geochronological update

3. Regional domain relationships

4. Summary

1. Paul Gilbert (Manitoba Geological Survey)1: 20 000 scale mapping

2. Manuel Duguet (Post doctoral student, Univ. of Waterloo)Regional mapping (1: 50 000 scale) with focus on structural geology

3. Paul Kremer (MSc graduate student, Univ. of Waterloo)Setting of TANCO pegmatite

4. Caroline Mealin (MSc graduate student, Univ. of Waterloo)Mapping of mafic-ultramafic Bird River Sill (PGE potential)

Bird River Belt projects initiated in 2005

Geologicaloverview

Bird River Belt Stratigraphy

1. MORB-type volcanic rocks

2. Arc-type assemblage

3. Younger sedimentary rocks

Bird River Belt stratigraphy –east part

Maskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000mN

.

740000mE.

558

2500

mN

.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winnipeg River

BRLS

Booster Lake Fo.

Lamprey Falls Fm (MORB)

Lamprey Falls Fm (MORB)

Flanders Lake Fo.

South panel arc

North panel arc

Bird River Belt stratigraphy –east part

Maskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000mN

.

740000mE.

558

2500

mN

.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winnipeg River

BRLSBooster Lake Fo.

Lamprey Falls Fm (MORB)

Lamprey Falls Fm (MORB)

FlandersLake Fo.

South panel arc

North panel arc

BirdRiverSill

Bird River Sill

• Mafic-ultramafic sill (Neoarchean 2745 ± 5 Ma)

• First explored 1898• Chromite deposits identified 1940’s; current

exploration for PGE (± Ni, Cu, Zn)

Mafic-ultramafic intrusions (PGE, Cr, Ni, Cu)

English River

Bird River

Uchi

Winnipeg River

Mayville

Domains

Bird River Sill

Maskwa granitoid bathlolith

Winnipeg River LFF

MORB-type Lamprey Falls Formation (LFF)

North flank LFF

South flank LFF

Maskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000mN

.

740000mE.

5582

500m

N.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winnipeg River

BRLS

Arc-type rocks

Cordierite schist

Maskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000mN

.

740000mE.

5582

500m

N.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winnipeg River

BRLS

Volcanogenic cglm

Debris flow

Chert

Turbidite

Younger sedimentary rocksMaskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000mN

.

740000mE.

5582

500m

N.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winnipeg River

BRLS

Flanders Lake Formation

Flanders Lake Formation

Turbidite AreniteConglomerate

Booster Lake

Formation

Bird River Belt Geochemistry

• MORB-type basaltic rocks

• Arc-type assemblage ~

North panel… calc-alkaline

South panel… tholeiitic

Bird River Belt - Geochemistry

BRBSouth Panel ~north

central

.1

1

10

100

Th Nb La Ce NdSm Zr Hf Eu Ti Gd Dy Y Er Yb Lu

Rock/NMORB Stern et al., 1995 (FFB Ocean Floor paper)

Birse Lake section northBirse Lake section central

BRB North panel

.1

1

10

100

Th Nb La Ce Nd Sm Zr Hf Eu Ti Gd Dy Y Er Yb Lu

Rock/NMORB Stern et al., 1995 (FFB Ocean Floor paper)

BRB north panel arc-type rocksMaskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000m

N.

740000mE.

5582

500m

N.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winn ipeg River

BRLS

.1

1

10

100

Th Nb La Ce Nd Sm Zr Hf Eu Ti Gd Dy Y Er Yb Lu

Roc

k/N-

MO

RB

Birse Lake section south - MORB type basaltLamprey Falls Formation (BRB north flank and Winnipeg River suites)Lamprey Falls Fo.

N-MORB normalized-extended element plots

Al O2 3 MgO

FeO+Fe O +TiO2 3 2

Komatiitic

Tholeiitic

Calc-Alkalic

BRB north panel arc-type rocksBRB south panel arc-type rocks

Alk MgO

FeO*

Calc-Alkaline

Tholeiitic

BRB north panel arc-type rocksBRB south panel arc-type rocks

AFMJensen cation diagram

Maskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000m

N.

740000mE.

558

2500

mN

.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winnipeg River

BRLS

BRB South panel -tholeiitic

BRB North panel –calc-alkaline

BRB North panel–calc-alkaline

BRB South panel –tholeiitic

Arc volcanic rocks

Summary of Geochemistry

Th Nb/16

Zr/117

A

B

C

D

A = N-MORB

B = E-MORB

C = OIB (Rift)

D = Arc-basalts

BRB south panel arc (TH)

Lamprey Falls Formation (MORB-type)North flankSouth flank

BRB north panel arc (CA)

Ternary diagram of Wood, D.A. (1980)

Bird River Belt Geochronology

Bird River Belt Geochronology (2.745 - 2.697 Ga)

Maskwa Lake Batholith BLS

HJS

Lac du Bonnet Batholith

Birse Lake pluton

Marijane Lake

pluton

Man

itoba

Ont

ario

775000mE. 5600000mN

.

740000mE.

558

2500

mN

.

PMAP 2006-8

0 10

kilometres

BernicLake

ShatfordLake

BirseLake

GreerLake

OsisLake

RushLake

Bird

Lake

BoosterLake

Tulabi Lake

Obrien Lake

FlandersLake

RyersonLake

EaglenestLake

Winnipeg River

BRLS Booster Lake Fo.2.712 ± 17 Ma

North panel arc2.740 ± 4 Ma

South panel arc(6 m yrs younger than north panel)

Flanders Lake Fo.2.697 ± 18 Ma

Bird River Sill2.745 ± 4 Ma

2.660 Ma

2.782 Ma, 2.844 Ma

Geological Domains in SW Superior Province

English River (2.70)

Bird River (volc 2.74)

Uchi (2.90 – 2.70)

Winnipeg River(3.4 – 2.8)

English River paragneiss (2.70)

Flanders Lake Fo. sediment (2.70)

Domains in SW Superior Province

Lake WinnipegNorth Caribousuperterrane

Uchi

English River

Winnipeg River

Lake Superior

Transect Line

Ont

WinnipegRiver

terrane

Man

Ont

North Caribousuperterrane

South-north Transect

Western Superior Province: ages3.9 – 2.8 Ma

3.0 – 2.87 Ma

2.70 Ma

2.74 – 2.70 Ma

3.4 - 2.8 Ma

Detrital zircon data: provenance of younger sedimentary rocks

Booster LakeFormation

(2.712 ± 17 Ma)

Flanders LakeFormation

(2.697 ± 18 Ma)

2.720 Ma

3.025 Ma

3.430 Ma

3.500 Ma2.600 Ma 3.050 Ma

North CaribouSuperterrane

(3.0 – 2.8)

English River(2.70)

WinnipegRiver

(3.4 – 2.8)

Scale

T = 35

T = 49

Summary

Bird River Belt is the subject of ongoing mapping by MGS in support of current exploration for PGE, base-metals and rare-element bearing pegmatites. New data will focus on the west part of the belt.

Post arc volcanism.. collisional tectonics and synorogenic sedimentation ~ turbidite-type marine and fluvial-alluvial continental sediments(postdate volcanics by 10 – 20 m. yrs).

These ‘younger’ sedimentary rocks are apparently derived both from volcanic rocks and granitoid plutons in flanking continental terranes. They are structurally emplaced and may be allochthonous fault slices derived from the adjacent English River Domain north of Bird River Belt.

Neoarchean Bird River Belt consists mainly of arc-type rocks that were deposited on the margins of a flanking continental terrane.Arc-type components include~ tholeiitic, calc-alkaline and MORB-type basalts (arc-rift origin?).