Beaver Bay Beaver Bay ComplexComplex

Hypabyssal mafic, intermediate and felsic intrusions that occur within the medial and upper parts of the volcanic edifice of the North Shore Volcanic Group (NSVG)

Beaver Beaver Bay Bay ComplexComplex

Circa 1982

1985

Jim, Bernie, Colin, Jane, Steve

Jim D Mike S Terry B Jim

1987Crew1

19871987Crew 2Crew 2

Terry B Jim Susan B

Dean P

Susan B Terry B Jim

COGEOMAP

1985-1992

Dan H Terry B Dusty E Jim Colin R

1986

19891989

Jim Robbie L Nancy N Eric J

Eric J Kirby Jim

1990 & 1991

PROJECT

Beaver Bay ComplexBeaver Bay ComplexCirca 2001

sbi – Silver Bay intrusionsbrd – Beaver River diabasevhod – Victor Head diabaseslg/slt – Sonju Lake intrusionhct – Houghtaling Creek troctolitedfgn – Dam Five gabbronoritewlfd – Wilson Lake ferrodioriteelod – Elbow Lake olivine diabasefrg/frqm – Finland granophyrellg – Lax Lake gabbrobld – Blesner Lake dioriteumrg – Upper Manitou River gabbroccpd – Cabin Creek porphyritic dioriteslid – Shoepack Lake inclusion-rich diorite

FinlandGranite

Sonju LakeIntrusion

Lower Troctolite

Upper Gabbro

Lax LakeGabbro

Blesner Lake Diorite

Victor HeadOphitic Diabase

Beaver RiverDiabase

FTM

D

Silver BayIntrusions

SOUTHERN BEAVER BAYCOMPLEX

Ferromonzonite

Leucogranite

Structural Complexity in the Tettegouche Park area

Geologic Control on Topography in the Tettegouche areaGeologic Control on Topography in the Tettegouche area

HoughtalingCr troctolite

Beaver River Diabase

Silver Bay IntrusionsUpper ManitouRiver Gabbro

Cabin CreekPorphyritic Diorite

Dam FiveGabbronorite

Wilson LakeFerrogabbro

Shoepack LakeInclusion-rich

Diorite

Fourmile LakeFerrogabbro

Elbow Lake Ophitic Diabase

FTMD

NORTHERN BEAVER BAY COMPLEX

AnorthositicSeries (DC)

Felsic Series (DC)

EASTERN BEAVER BAY COMPLEX

HoughtalingCr Troctolite

Carlton PeakAnorthosite

Beaver River Diabase

Leveaux Porphryritic Diorite

FTMD

FTMD

FTMD – Finland Tectono-magmaticDiscontinuity

Western Beaver Bay Complex

CLLS - Cloquet Lake Layered Series

BBC Magma CompositionsBBC Magma Compositions

Na2O+K2OMgO

NSVG Lava TypesOT – olivine tholeiite (pot-primitive OT)TB – transitional basaltA – andesiteFA – ferroandesiteI – icelanditeR -rhyolite

Origin of Anorthositic Rocks of the Origin of Anorthositic Rocks of the Duluth and Beaver Bay ComplexesDuluth and Beaver Bay Complexes

660000 670000 680000 690000 700000 710000 720000

660000 670000 680000 690000 700000 710000 72000052

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530

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05

310

000

5320

000

528

000

05

29000

05

3000

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10000

532

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660000 670000 680000 690000 700000 710000 720000

660000 670000 680000 690000 700000 710000 720000

528

000

05

290

000

5300

000

531

000

05

3200

00

528000

05

290

000

53000

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053

200

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Far Northern Beaver Bay Complex?

Transition from DC to BBC MagmatismTransition from DC to BBC Magmatism