How do you know you’re in a How do you know you’re in a world class Nickel camp?world class Nickel camp?world class Nickel camp?world class Nickel camp?

Steve BeresfordSteve BeresfordMEGWA Jan 2009MEGWA Jan 2009

114m @4% Ni

“From little things big things grow”

Voisey’s Bay

Eastern DeepsFar Eastern Deeps

Ovoid

Discovery Hill

Western Extension

Reid Brook Zone

The individual intrusions within the cluster are The individual intrusions within the cluster are connected in 3D!connected in 3D!connected in 3D!connected in 3D!

Slide courtesy Dawn Evans-Lamswood

OutlineOutlineOutlineOutlineIntroductionIntroduction•• World class World class –– do we know what it means?do we know what it means?•• ConfidenceConfidence

Discovery HistoryDiscovery History•• Geology and predictive conceptsGeology and predictive concepts

Mineral systems and Target contextMineral systems and Target contextDeposit summaryDeposit summaryCamps Camps –– what are they?what are they?•• World class deposits are clusteredWorld class deposits are clustered

I t i ti it d idI t i ti it d id•• Intrusive connectivity and corridorsIntrusive connectivity and corridors

Staging systems and camp footprintsStaging systems and camp footprints•• Accommodation space and stress regimeAccommodation space and stress regime•• Accommodation space and stress regimeAccommodation space and stress regime

What is a camp?What is a camp?

ConfidenceConfidenceConfidenceConfidence

Through predictive conceptsThrough predictive conceptsMineral Systems approach Mineral Systems approach (do more than use the word (do more than use the word (do more than use the word (do more than use the word holistic)holistic)L th l f ld L th l f ld Learn the lessons from world Learn the lessons from world class discoveries. Visiting class discoveries. Visiting deposits are only junkets if deposits are only junkets if that is your attitudethat is your attitudeyy

Mineral systems approach Mineral systems approach -- understand the target contextunderstand the target context

OREOREDEPOSITDEPOSITDEPOSITDEPOSITSETTINGSETTING

DISTRICT DISTRICT ––SCALESCALESETTINGSETTING

PROVINCE/SUBPROVINCE/SUB--PROVINCEPROVINCE--SCALESCALETECTONIC SETTINGTECTONIC SETTING

GLOBAL GLOBAL -- SCALE GEODYNAMIC SETTINGSCALE GEODYNAMIC SETTING

Hronsky

World class deposits NiWorld class deposits Ni--CuCu--PGE are not PGE are not simply larger ‘common garden’ depositssimply larger ‘common garden’ deposits

Schodde and Hronsky 2006

World class NiWorld class Ni--CuCu--PGE deposits PGE deposits -- excludingexcluding komatiiteskomatiites-- excluding excluding komatiiteskomatiites

Sudbury CampNi metal tonnes

Duluth

y p

Voisey's Bay

Pechenga

Nk ti

Nebo-Babel

Selebi-Phikwe

Nkomati

0 5000000 10000000 15000000 20000000

Kabanga

Source: Host websites

0 5000000 10000000 15000000 20000000

Red line denotes 1.3MNiT cut off of Schodde and Hronsky (2006), a rough approximation for world class

Understand there is a Understand there is a continuum of Nicontinuum of Ni--CuCu--PGE stylesPGE stylescontinuum of Nicontinuum of Ni CuCu PGE styles PGE styles

and one predictive or detective technique will NOT workand one predictive or detective technique will NOT workand one predictive or detective technique will NOT work and one predictive or detective technique will NOT work for all stylesfor all styles

MgO

RaglanKambaldaNebo-BabelJinchuan

32% 7%Kabanga

PechengaPerseveranceMt Keith

Voisey’s Bay TatiNoril’sk

Magnetics Gravity

RaglanMt Keith Nebo-Babel

Jinchuang Gravity

Kabanga

PechengaPerseverance

Kambalda

Voisey’s Bay

TatiNoril’sk

PechengaRaglan KambaldaVoisey’s Bay

Noril’skJinchuan

Depth of emplacement

Base Surface

Valmaggia Perseverance

Mt KeithNebo-BabelJinchuan

Sally Malay

Base of LC

Surface

Pechenga

Raglan KambaldaVoisey’s BayNebo-Babel

Noril’sk

S source

Crustal

Valmaggia Perseverance

Mt KeithJinchuan

Mantle Crustal

Understand and invest in target context

Getting out and hitting rocks is crucial but not enough

Independent test of a good structureIndependent test of a good structureIndependent test of a good structureIndependent test of a good structure

Lahtinen et al 2007

It should be reused again and again eg Pechenga-Imandra-Varzuga

Beware of myths andBeware of myths and intellectual blindness

Manage heuristics and challenge dogma (it i th b i f l ti )(it is the basis of exploration)

No feeders, no funnelsNo feeders, no funnels: : the feeder model is the feeder model is missing the pointmissing the point

Naldrett

Adapted from Hoatson 2000

Myth: There are no world class examples of funnel shaped intrusion hosted Ni-Cu-PGE

Myth: conduits/pipes are notnecessarily feeders to large intrusions

depositsintrusionsThe ovoid is not the mouth of a large intrusion!

1. Breccia pipes1. Breccia pipes 2. Chonoliths or conduitsegeg AguablancaAguablanca, Carr Boyd, Carr Boyd eg Noril’sk, Nebo-Babel

Giant Mascot, BC

ChonolithChonolith definition:definition:

““a discordant igneous intrusion of irregular shape whicha discordant igneous intrusion of irregular shape whicha discordant igneous intrusion of irregular shape which a discordant igneous intrusion of irregular shape which has either been passively squeezed into a prehas either been passively squeezed into a pre--existing existing cavity or has actively forced apart the country rock. It’s cavity or has actively forced apart the country rock. It’s

relationship with the invaded country rock is very complexrelationship with the invaded country rock is very complexrelationship with the invaded country rock is very complex relationship with the invaded country rock is very complex and terms such as dyke, and terms such as dyke, laccolithlaccolith, etc., cannot be used, etc., cannot be used””

((TomkeieffTomkeieff, 1983, 1983). ).

Deposit characteristicsDeposit characteristics

<21 29-34 1-4 10-5029 34

>34 MgO wt%21-291-44-10

10 50

>50 sulfides wt%

I b i (di i i t f t t i b i )• Igneous breccias (discriminate from tectonic breccias)

• Hydromagmatic phases, pegmatoids, varied or taxitic texture –the volatile link 17% of the Siberian Traps is composed ofthe volatile link. 17% of the Siberian Traps is composed of pyroclastics

• Concentric crystallisation• Concentric crystallisation

•Well differentiated on scale of intrusive complex

Taxite or varied textured

Pipe-like bodies I: Plan

Jinchuan Kalatongke

Voisey’s Bay

Santa Rita

Aguablanca

2kmEagle

Nebo-BabelDouble Eagle

Nkomati

Noril’sk

TatiTalnakh

Pipe-like bodies II: cross section

Kharalakh Nebo-Babel

Kalatongke

200m

Nkomati

Eagle

Kabanga ?

Ban PhuchMirabela*

Pipes are only part of the intrusive complex!Pipes are only part of the intrusive complex!Pipes are only part of the intrusive complex!Pipes are only part of the intrusive complex!

WMN 44 WMN 34WMN 15WMN 44 WMN 34WMN 15

Babel ProspectBabel Prospect Nebo ProspectNebo ProspectEastEastWestWest

WMN 27WMN 21WMN 25WMN 25WMN 44WMN 18WMN 10WMN 12WMN 61WMN 34WMN 15WMN 27WMN 21WMN 25WMN 25WMN 44WMN 18WMN 10WMN 12WMN 61WMN 34WMN 15

? ? Lower Contact

R t S d

Massive Sulphides

Disseminated SulphidesDisseminated Sulphides

Nebo Mineralised Leucogabbronorite

Op enriched Gabbronorite

Babel Mineralised Gabbronorite

0 400

metres

800

Recent Sand

Granulite Dolerite

Cover Sequence

Opx enriched Gabbronorite

Gabbronorite

metresMarginal Breccia Zone Special Gabbronorite

Seat et al 2006

Sulfide are pooling/concentrating after crystallisation!Sulfide are pooling/concentrating after crystallisation!

Lightfoot and Zotov 2007Lightfoot et al 1999 Lightfoot and Zotov 2007

World class deposit rarely accumulate by gravitational settlingWorld class deposit rarely accumulate by gravitational settling

This is syn‐emplacement mobilisation not solid state remobilisationnot solid state remobilisation

This is a syn‐magmatic breccia not remobilsation

Magmatic breccia rimming the Ovoid, Voisey’s Bay

This is remobilisation!

Clustering

Not all the elements of the cluster are mineralised. This will become important

-Emplacement level-Erosional level-Stress regime

How are deposits linked?How are deposits linked?ppWe don’t deliberately target or drill barren domainsWe don’t deliberately target or drill barren domains

Slide courtesy Dawn Evans-LamswoodSlide courtesy Dawn Evans-Lamswood

I th ti tI th ti tImage the entire ore system as Image the entire ore system as early as possibleearly as possibley py p

Wilson 2002Wilson 2002Wilson 2002Wilson 2002

Lesson from modern systems

Shervais et al 2006Marsh 1998

“World class Ni“World class Ni--CuCu--PGE deposits are the surface PGE deposits are the surface manifestation of crustal scale intrusive complexesmanifestation of crustal scale intrusive complexes””manifestation of crustal scale intrusive complexesmanifestation of crustal scale intrusive complexes

Noril’sk- Talnakh

Eagle

50km

Imaging the ore system

Pellerin et al

Accommodation space Accommodation space dd t it iand and stress regimestress regime

90% of 90% of magmatismmagmatism in modern rifts and in modern rifts and transpressionaltranspressionalbasins is focussed in accommodation zonesbasins is focussed in accommodation zones

Regional Fault Regional Fault

Regional Fault

Local dyke swarm

Intrusive cluster

Intrusive cluster

Intrusive cluster

Local dyke swarm

Regional Faultt us e c uste

Regional Fault

Local dyke swarm

Regional Fault

Schematic Cross Section: Relationships Between Deposits, Structure, and Transfer of Silicate and Sulphide Magma

Upper Chamber(Eastern Deeps)

Sulphide Emplacement

Sulphide Trap

Ovoid and Mini‐Ovoid Zones

Lower Conduit

Conduit DykeConduit Dyke

Sulphide Entrainment

Lower Chamber

Crustal Extension Crustal Extension

Troctolite

Lower Chamber

(Western Deeps)

Massive Sulphide

Pre‐intrusivefaults/joints Geological relationships from 

Li h f d N ld (1999)faults/joints

Syn‐emplacement faultLightfoot and Naldrett (1999); structural interpretation from Cruden et al., (2000)

ConclusionsConclusions• Invest in developing confidence in your targetsp g y g

• Understand the target context. It’s not arm wavering, its the difference between chasing any common garden deposit and world class.

• Getting out and hitting rocks is crucial but a poor target is a poor target. Improve your probability of success

• World class systems are clustered (it’s what makes them world class). Invest early in mapping the whole system and corridor (use

i t t l d i ) If f thi l it t l i l

• Chonoliths are not feeders to intrusions. They are parts of networks or

appropriate tools and spacing). If for nothing else it generate geological targets.

y pa corridor of intrusions which often include larger receptacles (layered intrusions) and passively emplaced dykes and sills.

•These ‘camps’ include a diversity of deposit styles reflecting the diversity of intrusive styles, assimilation histories, magma evolution, and evolving/fluctuating S solubility.

“World class Ni-Cu-PGE deposits are the surface manifestation of crustal scale intrusive complexes”

AcknowledgementsAcknowledgementsAcknowledgementsAcknowledgements

Colleagues at newgenco and UWAColleagues at newgenco and UWAFormer colleagues at WMC/BHPB for Former colleagues at WMC/BHPB for Former colleagues at WMC/BHPB for Former colleagues at WMC/BHPB for ‘the culture’‘the culture’Host of industry collaborators, Host of industry collaborators, y ,y ,colleagues, and studentscolleagues, and students