THE WEST MUSGRAVE: A POTENTIAL THE WEST MUSGRAVE: A POTENTIAL WORLD-CLASS NI-CU-PGE SULPHIDE AND WORLD-CLASS NI-CU-PGE SULPHIDE AND

IRON OXIDE CU-AU PROVINCE?IRON OXIDE CU-AU PROVINCE?

I.M. Grovesfor

D.I Groves, I.M. Groves, S. Gardoll, W. Maier & F.P BierleinRedstone Resources and Centre for Exploration Targeting, UWA

AIG 2007, Perth, June 2007

THE WEST MUSGRAVE: A FRONTIER TERRANETHE WEST MUSGRAVE: A FRONTIER TERRANE

• One of the last frontiers for mineral exploration in AustraliaOne of the last frontiers for mineral exploration in Australia

• Remote location in central AustraliaRemote location in central Australia

• Most prospective ground is under cover despite mineral Most prospective ground is under cover despite mineral occurrences known since 1950soccurrences known since 1950s

• Access for exploration companies difficult in past due to Access for exploration companies difficult in past due to restrictions imposed by traditional ownersrestrictions imposed by traditional owners

BUTBUT

• Recent access approved through structured agreements Recent access approved through structured agreements with well organized land councilswith well organized land councils

• Rapid exploration success initially by Western Mining Rapid exploration success initially by Western Mining CorporationCorporation

LOCATION - LITHOSPHERIC TRIPLE POINT JUNCTIONLOCATION - LITHOSPHERIC TRIPLE POINT JUNCTION

Redstone Resources

7300km2

GEOLOGICAL HISTORY OF WEST MUSGRAVEGEOLOGICAL HISTORY OF WEST MUSGRAVE

• Probable Archaean or Palaeoproterozoic lithosphereProbable Archaean or Palaeoproterozoic lithosphere

• caca 1600 – 1300 Ma amphibolite to granulite facies para- 1600 – 1300 Ma amphibolite to granulite facies para- and ortho-gneissesand ortho-gneisses

• Protoliths metamorphosed during Musgrave Orogeny Protoliths metamorphosed during Musgrave Orogeny caca 1200 – 1120 Ma1200 – 1120 Ma

• Emplacement of Bushveld-scale layered Giles Complex at Emplacement of Bushveld-scale layered Giles Complex at caca 1080 Ma at 33 – 16 km depth: most abundant rock types 1080 Ma at 33 – 16 km depth: most abundant rock types are olivine gabbronorite to gabbronorite and troctoliteare olivine gabbronorite to gabbronorite and troctolite

• Subsequent emplacement of smaller more-fractionated, Subsequent emplacement of smaller more-fractionated, shallow-level mafic intrusions: no published agesshallow-level mafic intrusions: no published ages

• Later emplacement of A-type granites: roughly same age Later emplacement of A-type granites: roughly same age as Giles Complex probably as Giles Complex probably caca 1078 1078 MaMa

OUTCROP MAP OF WEST MUSGRAVE - GSWAOUTCROP MAP OF WEST MUSGRAVE - GSWA

MUSGRAVE – MINERAL OCCURRENCESMUSGRAVE – MINERAL OCCURRENCES

MULTIPLE MINERALISATION STYLES WITH WORLD-CLASS ANALOGUESMULTIPLE MINERALISATION STYLES WITH WORLD-CLASS ANALOGUES

MUSGRAVE – CONCEPTUAL MODELMUSGRAVE – CONCEPTUAL MODEL

Babel NeboBabel Nebo

WingellinaWingellina

50 km50 km

90% of Region Covered by Shallow Sand, Calcrete and Colluvium,

Limiting Exploration in the 50s and 60s

OPPORTUNITY – GEOCHEMISTRYOPPORTUNITY – GEOCHEMISTRY

GEOLOGY OF NEBO & BABEL DEPOSITSGEOLOGY OF NEBO & BABEL DEPOSITS

From Seat et al (2007)

3D MODEL OF NEBO & BABEL DEPOSITS3D MODEL OF NEBO & BABEL DEPOSITS

From Seat et al (2007)

CROSS SECTION THROUGH NEBO SHOWING CROSS SECTION THROUGH NEBO SHOWING MASSIVE SULPHIDEMASSIVE SULPHIDE

From Seat et al (2007)

From Seat et al (2007)

GEOCHEMISTRY OF NEBO & BABEL DEPOSITS GEOCHEMISTRY OF NEBO & BABEL DEPOSITS SHOWING HIGH Zr (HIGHLY FRACTIONATED)SHOWING HIGH Zr (HIGHLY FRACTIONATED)

MUSGRAVE – BLACKSTONE “SATURN”MUSGRAVE – BLACKSTONE “SATURN”

Babel NeboBabel Nebo

WingellinaWingellina

50 km50 km

GEOCHEMICAL TARGETS BLACKSTONE/TOLLUGEOCHEMICAL TARGETS BLACKSTONE/TOLLU

10km

Titan North Cu

5km

INSTANT GEOCHEMISTRY - XRFINSTANT GEOCHEMISTRY - XRF

HALLEYS Cu GEOCHEMISTRY AND HALLEYS Cu GEOCHEMISTRY AND AEROMAGNETICS (RMC FARM- IN)AEROMAGNETICS (RMC FARM- IN)

1 km

> 500ppm Cu

> 300ppm Cu

> 200ppm Cu

> 120ppm Cu

PGE GEOCHEMISTRY OF HALLEYS GOSSANPGE GEOCHEMISTRY OF HALLEYS GOSSAN

DRILLING RESULTS - HALLEYSDRILLING RESULTS - HALLEYS

Large thickness (>74m) of disseminated Cu-PGE rich Large thickness (>74m) of disseminated Cu-PGE rich sulphides in fractionated Zr rich intrusionsulphides in fractionated Zr rich intrusion

50m50m

ANALOGY WITH PLATREEF OF BUSHVELD COMPLEXANALOGY WITH PLATREEF OF BUSHVELD COMPLEX

Adapted from Kinaird (2005)

LAYERED INTRUSION DEPOSIT STYLES LAYERED INTRUSION DEPOSIT STYLES

INTERPRETATION OF HALLEYS RESULTSINTERPRETATION OF HALLEYS RESULTS

• Nebo-Babel system high Ni:Cu ratio (1:1 for Nebo-Babel system high Ni:Cu ratio (1:1 for disseminated and blebby type ores, higher for massive disseminated and blebby type ores, higher for massive sulphide - Seat et al. 2007) relative to Halleys Ni:Cu ratio sulphide - Seat et al. 2007) relative to Halleys Ni:Cu ratio of 0.2:1of 0.2:1

• Halleys may represent fractionated high tenor sulphide Halleys may represent fractionated high tenor sulphide system in high flow-through zone along discordant system in high flow-through zone along discordant margin of Saturn intrusionmargin of Saturn intrusion

• More Ni-rich sulphides potentially to the northwest along More Ni-rich sulphides potentially to the northwest along the marginthe margin

CONCEPTUAL MODEL – PLAN VIEW OF SATURNCONCEPTUAL MODEL – PLAN VIEW OF SATURN

Younger Fractionated Intrusion S - Saturated

Older layered Intrusion S – Unsaturated

CONCEPTUAL MODELCONCEPTUAL MODEL

B Section AB Section A• Concentration of sulphide Concentration of sulphide

droplets on intrusion margin – droplets on intrusion margin – turbulent flow zoneturbulent flow zone

• Partial crystallization of Fe-Ni Partial crystallization of Fe-Ni rich MSSrich MSS

• Continued flow of residual Cu-Continued flow of residual Cu-PGE rich sulphide liquid along PGE rich sulphide liquid along intrusion marginintrusion margin

• Progressive deposition along flow through zone (Halleys, Titan etc)Progressive deposition along flow through zone (Halleys, Titan etc)

• Main Ni-Cu-PGE sulphide deposit lower in the intrusionMain Ni-Cu-PGE sulphide deposit lower in the intrusion

Cu PGE

Cu Ni PGE

Ni Cu PGE

MODEL – IOCG (Fe-OXIDE Cu-Au)MODEL – IOCG (Fe-OXIDE Cu-Au)

WORLD-CLASS POTENTIALWORLD-CLASS POTENTIAL

STRUCTURAL / INTRUSIVE CORRIDORSTRUCTURAL / INTRUSIVE CORRIDOR

COMPARISON OF WEST MUSGRAVE COMPARISON OF WEST MUSGRAVE & CARAJAS& CARAJAS

GEOLOGICAL SETTING ANALOGOUS TO WORLD-CLASS GEOLOGICAL SETTING ANALOGOUS TO WORLD-CLASS

CARAJCARAJÁÁS IOCG PROVINCES IOCG PROVINCE

WEST MUSGRAVECARAJÁS PROVINCE - BRAZIL

Coincident bull’s-eye

gravity and magnetic

high

Geophysical response

similar to Olympic

Dam and Prominent

Hill

COINCIDENT GRAVITY / MAGNETIC ANOMALY COINCIDENT GRAVITY / MAGNETIC ANOMALY

OLYMPIC DAM ANALOGUEOLYMPIC DAM ANALOGUE

GRAVITY IMAGE OLYMPIC DAM

BAGGALEY HILLS – Cu-Au (IOCG) or Ni-CuBAGGALEY HILLS – Cu-Au (IOCG) or Ni-Cu

GRAVITY IMAGE BAGGALEY HILLS

DETAILED AEROMAGNETIC SURVEY BAGGALEYDETAILED AEROMAGNETIC SURVEY BAGGALEY

10km

BAGGALEY HILL IRON OXIDE COPPER GOLD TARGETS BAGGALEY HILL IRON OXIDE COPPER GOLD TARGETS (IOCG) OVER DETAILED TMI AEROMAGNETICS (IOCG) OVER DETAILED TMI AEROMAGNETICS

5km

SUMMARYSUMMARY

• West Musgrave is one of the last frontiers for exploration in West Musgrave is one of the last frontiers for exploration in AustraliaAustralia

• It is a unique tectonic environment at the triple-point junction of It is a unique tectonic environment at the triple-point junction of three cratonsthree cratons

• Despite limited exploration, potentially world-class Ni-Cu-PGE Despite limited exploration, potentially world-class Ni-Cu-PGE sulphide deposits and Ni laterite deposits are already knownsulphide deposits and Ni laterite deposits are already known

• Recent high-resolution aeromagnetic data define a structural Recent high-resolution aeromagnetic data define a structural corridor in which discrete subcircular intrusions of fractionated corridor in which discrete subcircular intrusions of fractionated basic magma and A-type granite magmas were emplacedbasic magma and A-type granite magmas were emplaced

• This coincides with a lack of exposure with thin regolith coverThis coincides with a lack of exposure with thin regolith cover

• First Pass exploration by Redstone identifies numerous First Pass exploration by Redstone identifies numerous geochemical anomalies above thick zones of disseminated geochemical anomalies above thick zones of disseminated magmatic sulphides (on ground since August 2006)magmatic sulphides (on ground since August 2006)

• Further exploration is expected to confirm the potential of the Further exploration is expected to confirm the potential of the West Musgrave for magmatic Ni-Cu-PGE and IOCG depositsWest Musgrave for magmatic Ni-Cu-PGE and IOCG deposits

SUMMARYSUMMARY