magmatic ni-cu-pge deposits...cryptic craton margin ni-cu-(pge) deposits in the highly-mineralized...

SGS Open House – Dec 2015 – Lesher & Houlé

Magmatic Ni-Cu-PGE

Mineralization in

Canada

CM Lesher1 and MG Houlé1,2 1Laurentian University, Goodman School of Mines, Sudbury

2Geological Suruvey of Canada, Québec


Overview Ni-Cu-PGE mineralization in Canada is associated

with a wide range of ages, parental magma

compositions, geologic settings, host unit

geometries, and tectonic settings

Archean deposits (Abitibi, McFauld’s Lake) are

generally higher grade, but smaller

Proterozoic deposits (Sudbury, Raglan,

Thompson, Voisey’s Bay, Grenville) are generally

lower grade, but can be very large

Phanerozoic deposits (Wellgreen, Turnagain, Giant

Mascot) are generally small and most are

subeconomic


< 5

5-20

20-50

50-100

100-200

200-500

500-20000

Contained Ni (kt)

Canadian Ni-Cu-(PGE) Endowment


Raglan

Lesher 2007 GAC-MDD Spec Publ 5


Raglan Lesher 2007 GAC-MDD Spec Publ 5

gabbro

m$

gabbro

m$

Ccp

Pn

Po

Mag

(Ol)


Thompson

Hosted by

(or located near)

UM sills that are

localized in S-

rich parts of the

Pipe Formation

Layton-Matthews et al. 2007 GAC-MDD Spec Publ 5


Thompson

Chr Ol

Ccp Pn

Po

Chr

Layton-Matthews et al. 2007 GAC-MDD Spec Publ 5

Disseminated

Ni-Rich Sediments

Breccia

Ore


Dumont

Sciorentino et al. 2015 Econ Geol


Dumont

Sciorentino et al. 2015 Econ Geol

1 Po-Pn-(Ccp)

2 Pn

3 Pn-Aw

4 Pn-Hz-Aw

5 Hz-Aw incre

asin

g

mo

dif

icati

on


Lynn Lake

L. Hulbert

GSC


Lynn Lake L. Hulbert GSC

dunite-pyroxenite-norite-

gabbro pipes


Lynn Lake Eckstrand & Hulbert 2007 MDD-GSC

SGS Open House – Dec 2015 – Lesher & Houlé after Hulbert 2002 GSC

Wellgreen


Wellgreen www.welgreenplatinum.com

WS506-153/386-390’

2.76% Cu, 1.16% Ni

2.01 ppm Pt, 3.38 ppm Pd


Turnagain

Nixon et al. 2015 GSC TGI4

dunite

hornblendite >

< wehrlite

clinopyroxenite >


Grade-Tonnage


Grade-Tonnage Distribution

Resource (Kt)

0.1 1 10 100 1000 10,000

Jaireth Geo Sci Aust

Thompson

deposits are

larger

Probably a

reflection of

low magma:

sulfide ratio

(R factor)

100

80

60

40

20

0

Quantile

Deposits in

Abitibi are similar

to deposits in

Eastern Goldfields and

Southern Cross (WA)


Province/Domai

n

Examples

Age

Superior Shebandoan ON, Alexo-Dundonald, Langmuir-Redstone, Montcalm ON

Dumont, Marbridge QC

Eagle’s Nest-Eagle 2-AT12 ON

Thierry-Norton L ON

Mayville-Maskwa MB

2.7 Ga

Rae Ferguson Lake NU 2.7 Ga

Snowbird

Tectonic Zone

Nickel King NU

Axis Lake SK 1.9 Ga

Hearne Rankin Inlet NU 2.7 Ga

La Ronge

La Ronge

Rottenstone

Namew Lake MB

Lynn Lake MB

Rottenstone-Nemeiben SK

1.9 Ga

Circum-Superior Thompson MB

Raglan, Expo Ungava-Méquillon QC

Hopes Advance, Retty Lake, Blue Lake QC

1.9 Ga

Province/Domain I


Province/

Domain

Examples

Age

Southern Shakespeare ON 2.4 Ga

Sudbury ON 1.85 Ga

Nain Voisey’s Bay NL 1.33 Ga

Grenville Limerick ON

Lac Edouard, Renzy QC

1.4-1.2 Ga

Mid-Contient Rift Marathon ON

Great Lakes ON

1.1 Ga

Appalachian St Stephen NL 421-410 Ma

(Devonian)

Wrangell Wellgreen YK 232 Ma

(U Triassic)

Yukon-Tanana Turnagain BC 190 Ma

(Jurassic)

Coast Plutonic Giant Mascot BC

Cogburn BC

93 Ma

(L Cretaceous)

Province/Domain II


Eons Eras0

500

1000

1500

2000

2500

3000

3500

4000

Ma

AR

CH

EA

N

PR

EC

AM

BR

IAN

PR

OT

ER

OZ

OIC

PH

AN

ER

OZ

OIC

EOARCHEAN

PALEOARCHEAN

MESOARCHEAN

NEOARCHEAN

PALEO

PROTEROZOIC

MESO

PROTEROZOIC

NEO

PROTEROZOIC

PALEOZOIC

MESOZOIC

CENOZOIC

Abitibi-Wawa belt (ca. 2720-2710 Ma)

Lac des Iles (ca. 2689 Ma) Quetico intrusions (ca. 2690 Ma)

Lac Gayot (ca. 2880 Ma)

Circum-Superior (TNB - ca. 1881 Ma, CSB - ca. 1882 Ma, LBT - ca. 1884 Ma)

Turnagain (ca. 190 Ma)

Giant Mascot (ca. 93 Ma)

Wellgreen (ca. 232 Ma)

St. Stephen (ca. 421-410 Ma)

La Bostonnais Complex - Grenville (ca. 1390 Ma)

Sudbury Igneous Complex (ca. 1850 Ma)

East Bull Lake Suite (ca. 2490-2475 Ma)

Shakespeare - Nipissing Intrusive Suite (ca. 2217 Ma)

Voisey’s Bay - Nain Plutonic Suite (ca. 1334 Ma)

Muskox - Mackenzie magmatism (ca. 1270 Ma)

Coldwell / Thunder - Mid Continent Rift (ca. 1108 Ma)

Adamson River - Prince Albert Group (ca. 2970 Ma)

Lynn Lake (ca. 1870 Ma)

Ring of Fire - Bird River - BUOGE (ca. 2742-2734 Ma)

Baikie Showing - Florence Lake belt (ca. 3000 Ma)

Deposit Associations

Komatiite-associated

Gabbro-associated

Flood basalt-related

Impact-related

Orogenic-related

Ages


Cumulus

Phases

Parental

Magma

Canadian

Examples

Other

Examples

Ol high-Mg

kom

Alexo-Dundonald, Langmuir-Redstone,

Dumont, Marbridge, Sothman

Kambalda, Mt Keith,

Perseverance

Ol-Chr low-Mg

kom

Birchtree, Bucko,

Manibridge, Thompson

Ol-Chr-Cpx kom

basalt

Raglan

Expo Ungava-Méquillon

Ol-Chr-Cpx-

Plag flood basalt Wellgreen, Canalask Noril’sk

Ol-Chr-Opx-Cpx contaminated

kom

Namew Lake

Eagle’s Nest, Eagle Two, AT-12

Ol-Opx-Cpx

Ol-Cpx-Plag ferropicrite

Jinchuan

Pechenga

Ol-Plag high-Al basalt Voisey’s Bay

Ol-Cpx-Hb-

Phlog

ankaramite

(hydrous

picrite)

Turnagain

Ol-Opx-Hb contaminated

ankaramite? Giant Mascot, Cogburn

Opx-Plag Qtz diorite Sudbury

Cumulus Assemblages


Ore Compositions

Sudbury, Raglan, and

Thompson exhibit patterns

consistent with magmas

derived from from

peridotitic (normal

asthenospheric) mantle

Voiseys Bay exhibits a

pattern consistent with a

magma derived from

pyroxenitic (metasomatized)

mantle

data from Naldrett 2004 Springer

0.1

1

10

100

1000

10000

Pd Cu Pt Rh Ru Ni Ir Co

Me

tal/P

rim

itiv

e M

an

tle

Noril'sk Sudbury Duluth

Thompson Mt Keith Kambalda

Perseverance Raglan

0.01

0.1

1

10

100

1000

10000

100000

Pd Cu Pt Rh Ru Ni Ir Co

Meta

l/P

rim

itiv

e M

antle

Raglan Jinchuan

Pechenga Voisey's Bay


Tectonic Settings Divergent Margin

Continental Rift: Alexo-Dundonald, Langmuir-Redstone-

Sothman, Wellgreen

Rifted continental margin: Expo-Méquillon, Raglan,

Sudbury*, Thompson, Labrador Trough, Voisey’s Bay

Convergent Margin: Turnagain, Giant Mascot

Suprasubduction?

Local extension?

Post-orogenic?


Tectonic Settings

Mid-OceanRidge

RiftedArc

BackArc

OceanicIsland

RiftedMargin

ContinentalRift

Acoje(Philippines)

Krsaste(Albania)

JinchuanPechengaSudburyRaglan

ThompsonVoisey’s Bay

DuluthKambaldaMt KeithNoril'sk

ZimbabweAbitibi

Oxford-StullAbitibi?

Oxford-Stull?

AguablancaKotalahti-VammalaRåna & Vakkerlien

Selebi-Phikwe and TatiSally MalayWrangeliaQueticoGrenville

None Known

ConvergentMargin


1.9 Ga Circum-Superior Belt

Baragar & Scoates 1987 Geol Soc Spec Publ 33

TNB

Raglan

Sudbury

Location of

Sudbury is

coincidental,

but the

emplacement of

Ni-Cu-PGE

protores in

Nipissing and

East Bull Lake

suite intrusions

at 2.4 and 2.2

Ga was not!


Preferential Location along Craton Margins

History

First noticed by Newmont and Inco in the 1960s

Defined by Baragar & Scoates in late 1980s

Used by WMC in the 1990s

Concept

Craton keels impede

intrusion of magma

High-flux magmatism

is “steered” toward

craton margins

(Kerrich et al. 2005

Econ Geol 100th Anniv Vol)

from Begg et al. 2010 Econ Geol

A

SCLM

SCLM

crust

(paleo)craton margin

marginal basin

crustB

1

1

2

2

34

34


Snowbird Tectonic Zone

Mahan & Williams in press Geology

NK

NK: Nickel King

AL: Axis Lake

AL


Cryptic Craton Margin Ni-Cu-(PGE)

deposits in the

highly-mineralized

Kalgoorlie Terrane

(e.g., Kambalda-

Perseverance-Mt

Keith) formed along

the margin between

two cratons

Sm-Nd and Lu-Hf

isotopic data

needed to better

understand the

structure of our

cratons and their

SCLM roots

Map of Yilgarn Block showing Nd

isotope model ages of grantitic

plutons (Champion & Cassidy 2007

Geosci Aust) and location of highly-

mineralized Kalgoorlie Terrane


Geological Settings

Impact melt

sheet (Sudbury)

Volcanic (Alexo, Langmuir, Raglan)

Subvolcanic (Dumont, Eagle’s Nest, Expo Ungava,

Mequillon, Sothman, Thompson, Wellgreen)

Plutonic (Giant Mascot, Turnagain, Voisey’s Bay)

Jinchuan

DuluthPechengaMt Keith-Perseverance

Voisey’s Bay

ThompsonKabangaAguablanca

Alexo/Kambalda/Raglan

Deep Crust

Shallow Crust Noril’sk-

Talnakh

Sudbury


Lava/Magma Channelization Lava channels: Raglan

Channelized sheet flows: Alexo

Channelized feeder sills: Sothman, Thompson

Feeders: Lynn Lake, Eagle’s Nest, Méquillon,

Voisey’s Bay

Giant Mascot and Turnagain occur in composite

plutons/intrusions that have been proposed to be

emplaced as mushes (i.e., not flow-through systems

like high sulfide systems), which may be why they are

low grade

Sudbury occurs in an impact melt sheet


Asthenospheric Mantle

Langmuir ores

Langmuir BIF

Windarra ores

Windarra BIF

Kambalda ores

Tasuiak gneiss

Eastern Deeps

Kambalda sediments

Raglan ores

Raglan semi-pelites

Alexo ores

Thompson BIF

Thompson ores

Jinchuan ores

Alexo FW andesite

Duluth ores

Duluth sediments

Noril'sk economic Noril'sk uneconomic

Noril'sk barren

Nebo-Babel ores

Hart ores

Hart BIF (all facies)

Enderbitic gneiss

Ovoid

VTT and BBS

Discovery Hill

Reid Brook Zone

Fortaleza de Minas ores

Phoenix-

Selkirk ores

Phikwe-Phokoje-

Dikoloti ores

-18 -12 -6 0 6 12 18 24

d34S

Sulfur Sources

Voisey’s Bay

Raglan

Thompson

Alexo

Langmuir

Hart


Geological Model: Sulfide-Rich Deposits

Channelized parts of dynamic mafic-ultramafic magma

systems that provide heat to incorporate S from country rocks

and provide high magma:sulfide ratio (R factor)

Thermomechanical erosion of S-bearing country rocks,

normally at or near the same stratigraphic level

Upgrading of sulfide xenomelts PGE>Cu>Ni

Canadian Examples: Abitibi, Eagle’s Nest, Raglan, Thompson,

Voisey’s Bay

Other Examples: Jinchuan, Kamblada, Perseverance,

Noril’sk, Pechenga



Contamination and Metal Depletion in a

Dynamic Volcanic Ore-Forming System

Silicatexenomelt

Magma

Xenolith Sulfidexenomelt

Os-richmaficresidue?

Re & Os mobilized?

Unconsolidatedsulfidic interflowsediment

strong recrystallization

sulfide-out

country rock

graphite-out

Fe-Ni-Cu-(PGE)

sulfide meltS C

Thermo-mechanicalerosion

Contaminated,metal-depleted

lava

Uncontaminated,sulfide-undersaturatedmagma

Contaminatedsample

Xenovolatiles

Wholesale melting, incongruent melting, devolatilization, andcontact metamorphismof country rocks

Olivine

Lesher et al. 2001 Can Min



Lesher et al. 2001 Can Min

Decoupling of Lithophile and Chalcophile Components in and Thermal Aureole aroundMineralized Undifferentiated CumulateFeeder Sills in the Ospwagan Group

Misciblexenomelt

Xenolith?

'skarn'

carbonate-out

country rock

sulfide-out

sulfide meltSC

Thick partial/incongruent meltingcontact metamorphic profile(expected but not observed)

Immiscible sulfide

Contaminated

magma

Sulfide faciesiron-formation

Contaminated, fractionated, S-saturated CE depleted derivative magmalower Mg# HILE>MILENb/Nb* < 1 less +ve eNdmore +ve g Os

Uncontaminated, unfractionated, S-undersaturatedCE undepletedparental magma higher Mg# HILE<MILENb/Nb* ~ 1 eNd > 0g Os ~ 0

Mineralized undifferentiatedcumulate feeder sill

dunite


Geological Model: Sulfide-Poor Deposits

Magma contains enough S to generate low-grade

disseminated sulfides ± alloys via cotectic Ol-Sul

accumulation

Serpentinization may upgrade lower tenor magmatic Po-

Pn-(Ccp) assemblages to higher tenor pentlandite (FeNi)9S8,

heazlewoodite Ni3S2, and awaruite Ni3Fe bearing assemblages

Beware of resource estimates reporting total Ni rather than

sulfide-alloy Ni, as significant amounts of unrecoverable Ni may

be housed in silicates and oxides

Canadian Examples: Dumont, Turnagain

Other Examples: Mt Keith


Geological Model: Sulfide-Poor Deposits

Facies changes in dacite

result in different degrees

of thermomechanical

erosion

Ol-(Sul) cumulates form

in zones of high magma flux

Fiorentini et al. 2007 Econ Geol


Most Alaskan Complexes are deficient in sulfide because of

the elevated fO2 conditions in hydrated magmas generated

in the suprasubduction zone environments (e.g., Thakatura

et al. 2008 JGSI)

At high fO2 (>QFM+2), up to 10x more S may be dissolved

as sulfate (Jugo 2009 Geology)

Local enrichment in PGE alloys may occur in local

reducing environments during chromite crystallization

(Finnigan et al. 2008 J Pet)

Erosion of these generates characteristic placer

mineralization

Canadian Examples: Giant Mascot, Turnagain

Other Examples: Urals

Geological Model: Low-Sulfide Alaskan Complexes


Geological Model: High-Sulfide Alaskan Complexes

Requires assimilation of C-bearing country rocks to reduce

the fO2 of the magma and exsolve sulfide

Country rocks may also contribute S, resulting in a

spectrum from S contents depending on the

contaminant(s)

Early assimilation of S (prior to significant Ol crystallization)

generates Ni-Co-IPGE-rich, Cu-PPGE-poor sulfides

Late assimilation of S (after significant Ol crystallization)

generates Ni-Co-IPGE-poor, Cu-PPGE-rich sulfides

Canadian Examples: Samuels Lake (Quetico)?

Other Examples: Duke Island, Salt Chuck, Union Bay

SGS Open House – Dec 2015 – Lesher & Houlé Thakatura 2009 PhD Indiana U, Thakatura et al. 2008 JSG India; Thakatura et al. 2014 Econ Geol




Thakatura 2009 PhD Indiana U, Thakatura et al. 2008 JSG India; Thakatura et al. 2014 Econ Geol


Most Favourable Ingredients Source of large amounts of sulfide-undersaturated

magma over a short time period: mantle plumes appear to

be most favourable, but do not appear to be essential

Craton margins and/or crustal-scale faults: needed to

focus magma migration, but may not necessarily be nearby

Environment of emplacement containing an external

source of S (sediments, volcanics, or VMS mineralization)

essential for high-sulfide deposits

High-flow, dynamic environment: lava channel or magma

conduit to facilitate thermomechanical

erosion/devolatilization, high metal tenors, and/or

mobilization of sulfides

Favourable site for ore deposition: depending on fluid

dynamics of lava/magma emplacement


Acknowledgements NSERC Discovery and CRD Programs

Geological Survey of Canada

Ontario Geological Survey

Manitoba Geological Survey

Ministère des Ressources Naturelle du Québec

magmatic ni-cu-pge deposits...cryptic craton margin ni-cu-(pge) deposits in the highly-mineralized...

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