Ausim Uranium Conference 2012 Presentation

Mapping Calcrete Mineralogy using HyMap Imagery in Western Australia and Namibia M. Hussey and B. A. Martini HyVista Corporation 11/10 Gladstone Rd., Castle Hill, NSW, AUSTRALIA www.hyvista.com

Uranium Mapping Projects Four types of Uranium deposits successfully mapped thus far:  Unconformity associated – eg. Ranger (Alligator River) & Pine Creek, NT; Angelo River (Kurradong), WA  Surficial deposits, calcrete-hosted – eg. Mason Lake (Yeelirrie), WA; Langer Heinrich and Trekkopje, Namibia  Carbonatite associated – eg. Mud Tank, NT; Lofdal & Rossing, Namibia  Metasomatic – Valhalla, Bikini & Skal, Mt. Isa, QLD

Hyperspectral Imaging – Spectrometry From The Air

Spectral Regions Relevant to Geology  Visible and near infrared

400 - 1000 nm (VNIR)

 Iron oxides and iron bearing minerals (Hematite, Goethite, Jarosite)  Rare Earth Minerals  Vegetation

 Shortwave Infrared  OH-bearing minerals    

   

1000 - 2500 nm (SWIR)

Clay Minerals Micas Amphiboles Serpentine, Talc, Chlorites, Epidote

Phosphates Sulfates Carbonates Hydrocarbons    

Cellulose (Vegetation) Oils and Waxes (Petroleum and Vegetation) Plastics Methane

Spectral Signatures: Uranium Alteration Assemblages

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>1,000,000km2 worldwide

HyMap Instrument

Spectral Configuration – 128 channels

    

Module

Spectral range

Bandwidth across module

Average spectral sampling interval

VIS

0.45 – 0.89 um

15 – 16 nm

15 nm

NIR

0.89 – 1.35 um

15 – 16 nm

15 nm

SWIR1

1.40 – 1.80 um

15 – 16 nm

13 nm

SWIR2

1.95 – 2.48 um

18 – 20 nm

17 nm

SNR average of 1000:1 ~3-50m pixels (hardened for high-altitude, extreme cold and heat) 60° FOV (strip width ~2.5km at 5 m pixel, ~1.4km at 3.5 m) 1000km2/day (optimal conditions @ 5m) Seamless mineral mapping and geophysical/geochemical integration (~1-6 weeks)

Western Australia Uranium Deposits

Calcrete-hosted Uranium within the Murchison of the Yilgarn Craton www.dmp.wa.gov.au

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Yeelirrie, Yilgarn Craton, Western Australia World’s largest surficial, calcrete-hosted deposit  Located on the northern margin of the Yilgarn Craton in the Northeastern Goldfields; found in 1972 by WMC Resources (taken over by BHP in ‘05)  Mineralised calcretes formed above Archean granites and greenstones; ore zones are within the valley paleodrainage systems; all carnotite  Calcrete outcrop is poor with 1-2 m of sand loam and clay overburden

The Yeelirrie Pit, BHP Billiton

Yeelirrie HyMap Survey – Two flight lines at 4m resolution

Yeelirrie Alteration Mineral Map

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Yeelirrie Alteration Mineral Map – Mine Close-up

Yeelirrie Alteration Mineral Map: Deposit Alteration Model

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Lake Mason, Yilgarn Craton, Western Australia Surficial, calcrete-hosted deposit  Located approximately 80km southwest of the Yeelirrie deposit in the eastern Murchinson region of WA; found in the 1970’s by BP Minerals via shallow carnotite shows  Mineralised zones associated with the valley calcretes of the Lake Mason drainage system  Defined Mineral Resource of 9.1Mt U3O8 at 185 ppm U3O8 (100ppm cutoff)*

*figures downloaded from Energy Metals Limited, 5June2012

The sandstones of the central Yilgarn

A standard decorrelation stretch brings out gross lithology and mineral assemblages -Comparable to nearby Yeelirrie, the calcretes have formed over a similar granitoid basement

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Leveraging the 100 + bands of HyMap, we map specific mineralogy -Three types of clay (Halloysite, Kaolinite and Nontrite) are readily discriminated and mapped

Mineral mapping indicates paleochannels contain Gypsum, Mg-rich Smectiteâ&#x20AC;Ś

â&#x20AC;ŚDolomite and Calcite. The magnesium-rich smectite (mapped in red) may represent weathered dolomites at depth

HyMap-derived alteration maps provide a new way of mapping sub-surface and/or weathered calcrete bodies

Nambian Uranium Deposits Current mines produce approximately 10% of world Uranium demand - Langer Heinrich is the second largest mine in Namibia behind Rossing

Namibian Geologic Survey

Langer Heinrich, Damara Uranium Province, Namibia Surficial, calcrete-hosted deposit  Located approximately 80km east of Walvis Bay in central Namibia; found in 1973 by a large-area government sponsored airborne radiometric survey  Consists of seven mineralised zones within a 15km long paleodrainage system  Mineral resource of 74,415t U3O8 at a grade of 0.06% U3O8 (250ppm cutoff)*  Primary ore mineral is carnotite

From Paladin Energy Ltd.

*figures downloaded from Paladin, 5June2012

Langer Heinrich, Damara Uranium Province, Namibia

Langer Heinrich – Broad Lithologic Differentiation

Langer Heinrich – HyMap derived mineral map

Known mineralised calcrete bodies Calcite predominately defines the calcretes in this area

Residual muscovite rich sand partially covers some of the calcrete

Calcrete Exploration Targets

Conclusions  We have successfully mapped surficial calcrete-hosted uranium deposits in Western Australia and Namibia  Despite poor exposure, calcrete bodies are mappable using airborne imaging spectroscopy (eg. HyMap) via detailed detection of not only host carbonates, but also their weathering products  The large area coverage (coupled with high spatial resolution) afforded by airborne scanners provides new ways to:  Expand currently known deposits  Step out the boundaries of larger districts  Undertake pure, large-area, green-field exploration

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