HyMap Hyperspectral Surveys for Mineral Exploration

HyMap Hyperspectral Surveys for Mineral Exploration

HyVista Corporation

11/10 Gladstone Rd., Castle Hill, NSW, AUSTRALIA

www.hyvista.com

HyVista Background

HyVista Corporation is an airborne survey company flying HyMap hyperspectral scanners since 1998

Offices

Sydney, Australia – Engineering, survey logistics, pre-processing and environmental applications, software development

Melbourne, Australia – Data processing and geological applications

Systems

Two 128-channel HyMap Scanners

One 96-channel HyMap MK1

Staff

Sydney – 4 Engineers, Logistic Manager, Data Manager , BD Manager and Software developer

Melbourne – Principal Geologist

© 2012 HyVista Corporation Pty. Ltd.

Spectral Geology

Spectral geology is used to identify minerals

Indicators of primary rock type

Signatures of alteration in mineralised environments

Indicators of weathering regimes and processes

Indicators of mineral chemistry & formation temperature.

Spectral Geology is the fundamental background for interpretation of Remotely Sensed Images

Hyperspectral images map areas that are spectrally unique at the surface

Mineral maps can be produced from hyperspectral images


Spectral Geology Concept - Recording Spectra

VNIR SWIR1 SWIR2


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 1000 - 2500 nm (SWIR) OH-bearing minerals

Clay Minerals Micas Amphiboles Serpentine, Talc, Chlorites, Epidote

Phosphates Sulfates Carbonates Hydrocarbons

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


VNIR Fe-Oxide Spectral Signatures


Al - OH (2170 - 2210 nm) Pyrophyllite, Kaolinite, Montmorillonite, Muscovite + Illite (White Micas)

Fe – OH (2250 - 2300 nm) Nontronite, Fe Smectite

Mg – OH (2300 - 2400 nm) Chlorite, Talc, Epidote, Amphiboles, Serpentines, Phlogopite, Saponite, Vermiculite

Si – OH (2240 nm -broad) Opaline Silica, Hemimorphite (Zn silicate)

Carbonates (2310nm-2340nm) Calcite, Dolomite, Magnesite, Siderite, Sauconite (Ferroan species show broad absorption

< 1000 nm)

Sulphates (1700nm and 2160nm) Jarosite, Alunite, Gypsum, Anhydrite

SWIR Minerals


SWIR Mineral Spectral Signatures


Hyperspectral and Multispectral DifferencesHyperspectral imaging is part of a class of techniques commonly referred to as spectral

imaging or spectral analysis. Hyperspectral imaging is related to multispectral imaging. The

distinction between hyper- and multi-spectral is sometimes based on an arbitrary "number of bands"

or on the type of measurement, depending on what is appropriate to the purpose.

ASTER MINERAL MAP HyMap MINERAL MAP

Why Hyperspectral?


Hyperspectral Imaging – Spectrometry From The Air


HyMap Imaging System Aircraft Mounting & SpecificationsSPECIFICATIONS

IFOV: 2.5 Mr Along Track, 2.0 Mr Across Track

FOV: 61.3o (512 Pixels)

GIFOV: 3m-15m (Flying Heights 2,000m-7,000m)

Spectral Bands: 128

Band Width: ~14nm-17nm

•VNIR: ~400-1000nm

•SWIR: ~1000-1400nm

•Swir1:~1400-1995nm

•Swir2:~2014-2488nm

SNR: > 800:1 ( 50% Reflector At Noon)

Data Collection Rate: 4 Gigabyte/Hour

Daily Cover: 1200km2- 2500km2 (5m - 10m Pixels)

Data Collection +/- 2 Hours Solar Noon

Zeiss Stablised Platform to Minimise Distortions

Geometric Correction:

+/- 10m ( IMU/GPS)

The system is flown in a light aircraft at 1750m to

5,000m A.G.L. And can collect data up to 2200

km2 per survey day.


HyMap Hyperspectral Scanner – Optimal Survey Conditions

Sun angle >40o

Less than 25% cloud cover

Dry surface

>30% Bare ground

No No No

Yes

YesYes

Yes


HyMap scanners have completed mineral mapping projects in over 30 countries from Afghanistan to Zimbabwe for geological survey organisations and for mining / exploration companies

Mongolia Afghanistan

Afghanistan

whole country @ 30m pixels

Total Survey Areas (1996-2009) >1,000,000km²


Spectral Processing and Mineral Mapping -Converting Reflectance Images Into Mineral Maps

Unsupervised Endmember Unmixing

Identifies specific spectra from within the data and maps

Supervised Spectral Matching (LO, MF,MTMF,SAM)

Maps the distribution of a specified spectrum

Reflectance Images

32 Bands 15 EM

Mineral MapImages

Identified Spectra


Processing Flow Chart

DCS CC Carbonate (Red)FeOH (Green)MgOH (Blue)

MNF CCBand 2 (Red)Band 3 (Green)Band 4 (Blue)

Mineral Map CCKaolinite (Red)Paragonite - White Mica (Green)Muscovite - White Mica (Blue)

Overview CCBand 28 (Red)Band 15 (Green)Band 3 (Blue)

Level 1A Mosaic

Level 1B Data Cube

►Pre-processing on a strip by strip basis produces radiance and apparent reflectance Level 1A Mosaic.►Reflectance images are cross track, level corrected and geo-corrected.►Corrected strips are mosaiced into a seamless, homogeneous Level 1B data cube.►The data-cube is processed to produce various band colour composite (CC), minimum noise fraction (MNF), band ratio index images and image maps that highlight mineralogical and geological / chemical variations.


Level 2: Photo Interpretation Products (images that do not map minerals uniquely)

Overview Colour composites: Landsat TM 432 equivalent, true and false colour images

MNF Images from which 2-4 colour composites (CC) are produced

Decorrelation Stretch that can map the distribution of:

MgOH/CO3, FeOH, SiOH, ALOH, Argillic, Sulphate, Iron Oxides minerals but not specific minerals

Output images are written to ENVI, ER Mapper, ECW, Jpeg and GeoTiff formats

Conversion to .shp and .kmz also possible

HyVista Hymap Processing: LEVEL 2


Overview Colour Composite

RGB 108, 28,03

MNF Colour Composite

RGB 2,3,4

Mount Whale Back Iron Ore Mine, Hamersley Region, Western Australia (3.5m Pixel Resolution)



Decorrelation Composite

RGB 0.9um, 0.87um 2.32um


Mount Whale Back Iron Ore Mine, Hamersley Region, Western Australia, (3.5m Pixel Resolution)


Decorrelation Composite

RGB 0.9um, 0.87um 2.32um



Relative Band Depth Image

RGB Al-OH, Carbonate, Iron Oxide

Al-OH Minerals

Iron Oxide Carbonate Minerals


LEVEL 3: Mineral Abundance and Mineral Chemistry Image Maps

SWIR and VNIR Mineral Abundance Mapping:

Mineral abundance images are determined from end-member un-mixed images, Match Filtered, Logical Operator processed and presented as:

Thresholded Greyscale

Thresholded Pseudo Coloured

Mineral Map RGB Colour Composite

Rule Classified Multi Mineral Maps

Pseudo Coloured, Absorption Minima - Wavelength Shift for:

Illite Al content

FeOx type

Carbonate and Chlorite composition

The mineral mapping and mineral chemistry images can be presented as overlays onto a grayscale background (or other suitable imagery, eg. topo) and individual areas of mineral occurrence can be output as shape files (or kmz)

LEVEL 4: In collaboration with customer, more detailed processing can be carried out to locate minerals of specific interest in their area , e.g. rare earth and opaque minerals.




Greyscale Mineral Abundance Map

Goethite Threshold 90%

Pseudo Colour Mineral Abundance Map

Goethite Threshold 90%

HyVista Hymap Processing: LEVEL 3 Products


Mineral Map Colour Composite

RGB Goethite, Hematite, Chlorite

Rule Classified Mineral Map




Wavelength Shift Mineral Composition Image

Hematite to Goethite


Mount Whale Back Iron Ore Mine, Hamersley Region, Western Australia, 3.5m Pixel Resolution


HyVista HyMap Test Site Surveys: Porphyry and other Alteration System Deposits

USA

OATMAN (ARIZONA)

YERINGTON (NEVADA)

MEXICO

NW MEXICO SILVER-GOLD BELT

NAMIBIA

HAIB PROTEROZOIC Cu/Au PORPHYRY

AUSTRALIA

HALLS CREEK MOBILE BELT ARGILLIC ALTERATION

NULLAGINE


HYVISTA HYMAP SURVEY TEST SITE SURVEYS: Au OATMAN

Oatman Survey, Arizona, USA. HyMap Imagery, 5m pixels, Acquired 2003

Geology: Lies at the centre of a trachyte, latite, rhyolite fault-bounded, typical Basin and Range Tertiary volcanic complex.

Mineralisation: Epithermal vein deposit centred upon advanced argillic / argillic style hydrothermal alteration and radiating auriferous qtz-calcite±adularia veins. Ore deposited in dilatational zones as vein filling and complex stockworks.

Mineral Mapping: Identifying and mapping the minerals that characterise the alteration associated with the mineral occurrences at Oatman using HyMap imagery and comparison with results from ASTER Imagery.


EPITHERMAL GOLD Oatman Arizona

Colour Composite Ternary RGB Mineral Map Rule Class Mineral Map


Epithermal Gold Oatman Arizona: ASTER vs. HyMap

*Processed by M Brown

mappa mundi / Infoterra Ltd,

United Kingdom

GSRG Conference 2008

Mineral Mapping at Oatman, using

ASTER and HyMap

ASTER Mineral Map HyMap Mineral Map


HyVista HyMap Test Survey Sites: Porphyry System –Yerington, NV, USA

Yerington Survey, Nevada, USA. HyMap Imagery, 3.5m pixels, Acquired August 2009


Porphyry Systems: Yerington, NV, USA

Buckskin Range

Epithermal Alteration

Singatse Range Porphyry

Mineralisation

Ludwig / Douglas Hill

Skarn Mineralisation

Ann Mason

Minnesota Fe Mine

Buckskin Mine

Ludwig

Mason Valley Mine

Yerington Mine

The Yerington district, Nevada is

located in the western edge of the

Basin and Range Province in the

former site of a subduction-

related magmatic arc.

The district hosts several

porphyry copper deposits

(Yerington, Ann mason and Bear-

Lagomarsino) and Fe oxide-

copper gold lodes within a

Jurassic (Yerington) batholith and

volcanic cover. A number of

copper bearing skarn and

significant Fe oxide-copper-gold

deposits occur at the batholith’s

contact aureole.

A series of alteration systems

exist in the area:

Early potassic (phlogopite-

K feldspar)

Early sodic-calcic

(actinolite-oligoclase)

Late sodic (chlorite-albite)

alteration

Late sericitic alteration and

tourmaline breccias

Advanced Argillic

Alteration

Ludwig Skarn

These alteration systems are

exposed to different degress

within the region producing a

complex pattern of mineralogy.

Combining various the maps of

the various minerals obtained

from the HyMap data reveals

patterns of mineral association

that should be able to assist in

the understanding of the

complexity of this area.


Minimum Noise Fraction (MNF) transform hasbeen applied to the HyMap reflectance data(vegetation and shadow masked). From thesetransform images, colour composites havebeen produced.

The bands selected (1, 2 and 3) highlight thebleached epithermal altered terrain (light blue)along the Buckskin Range. Dumps associatedwith the Yerington mine are depicted in lightgreen hues. Similar hues are observed in theSingatse Range. Darker green hues appear tohighlight skarn terrain.

MNF COLOUR COMPOSITE



Amphibole is probably Actinolite and highlights sediments / volcanics hosting skarn style mineralisation in the Ludwig / Douglas hill / Mason Valley area.

Highlights sediments / volcanics hosting skarn style mineralisation in the Ludwig / Douglas hill / Mason Valley area, southern margin of the Yerington batholith.

Mineral Map Colour Composite Mineral Map Colour Composite





Longer wave Illite relatively widely distributed in the area and possibly related to sericite and / or sodic overprints. Shorter wave Illite appears to favour lower pH environments along the Buckskin Range; flanks advanced argillic alteration. Kaolinite highlights alteration in the Buckskin Range.


Illite 2190nm

Illite

Kaolinite 2

Advanced argillic alteration minerals highlight alteration in the Buckskin Range


Rule classified image 11 individual minerals

This image maps the hypogene minerals:

Sericite (Illite Al Poor and Rich))

Chlorite

Amphibole

Epidote

Topaz

Pyrophyllite

Goethite is mapping the pyritic zones



Epithermal Gold and Silver Exploration, Mexico

RADADERO

TONICHI

Surveys flown May 2007; pixel size of ~5m


Rodadero, NW Mexico


Rodadero, NW Mexico – Overview Colour Composite


DCS RGB Band 108 (Al-OH), Band 114 (Mg-OH and Carbonate), Band 30 (Fe Oxide)

Maps general distribution of main mineral classes in area

Rodadero Processing – Decorrelation Stretch Image


Argillic Alteration

Advanced Argillic Alteration

Rodadero Mineral Mapping – Selected Minerals


Rodadero Processing – Mineral Map


Rodadero Processing – Ternary Mineral Map


Tonichi, NW Mexico – Overview Colour Composite


Advanced Argillic

Alteration

Tonichi Mineral Mapping – Selected Minerals


Haib Survey, Namibia. HyMap Imagery, 5m pixels, Acquired October 2006

The early Proterozoic Haib porphyry copper deposit in Namibia clearly shows alteration zonation typical of this type of deposit.

Porphyry System Exploration, Haib, Nambia


Haib, Namibia – Overview Colour Composite

Core Area of Haib Porphyry System


The core area of the Haib Porphyry is the Phyllic Alteration Zone. It is surrounded by a Propylitic Zone. Advanced Argillic alteration occurs in localised in veins and discrete bodies. There is a central Potassiczone but it is characterised by feldspars that cannot be mapped directly with HyMap data.

Haib Processing – MNF Colour Composite


Haib Processing – Mineral Map – Propalytic Alteration


Haib Processing – Ternary Map – Phyllic Alteration

Phyllic characterised by Illites (White Mica) identified as Paragonite-Muscovite-Phengite from shift in main absorption feature


Haib Processing – Ternary Map – Argillic Alteration

Pyrophyllite identifies the argillic alteration within the phylliczone; tourmaline occurs in veins and some country-rock units


Haib Processing – Mineral Map – Propylitic/Phyllic Alt.


Halls Creek Mobile Belt, Kimberley Region, Western Australia. HyMap MKI Imagery, 5m pixels, Acquired Sept 2004

Regional Alteration Mapping, Halls Creek, WA, Australia


Area of Geology Map

X Cu/Pb/Zn

The images indicate that geology of

the area is more complex than existing

mapping indicates. However, these

images do not indicate the presence of

any alteration. There is one recorded

Cu/Pb/Zn prospect and the Grants

Creek Goldfield lies immediately to the

north of the area. The Halls Creek Gold

Field, Nicholson’s Find Gold Mine and

Angelo Gold Prospect area all located

less than 45Km SW of this area.

Halls Creek Processing

Overview Colour Composite Geology Map MNF Colour Composite


There are Four main areas of argillic alteration

in this area:

SE (SE) – occurs in an Al rich white mica unit

that corresponds to an granite unit and is

expressed as a marker unit showing zoning

within the granite.

Little Mount Isa (LMI) - area that is associated

with a ridge, within this unit, which is mainly

pyrophyllite, are zones of iron oxide., these

could be gossan; yellow on mineral map

colour composite

Halls Creek Fault Zone (HCF) - area of

alteration that lies along Halls creek fault north

of LMI..

Western Zone (WZ) – that is truncated by a

north south trending fault.

The LMI, HCF and WZ alteration lie to the east

and west of a unit that is dominated by Al poor

white mica but immediately bounded by

muscovite white mica.

This alteration probably results from a large

hydrothermal event possibly structurally

associated with the Halls Creek Fault, though

large hydrothermal events do occur elsewhere

in the Kimberley region.

SE

LMI

HCF

WZ

LMI

Halls Creek Processing: Mineral Maps

Mineral Map Colour Composite Rule Classified Mineral Map


Nullagine Survey, Hamersley Region, Western Australia. HyMap Imagery, 5m pixels, Acquired August 2009

Gold Exploration, Nullagine, WA, Australia


Part of SF5105 Geology Map (HyMap data extends beyond map to west and south).

To the south of the Middle Creek Line (southern set of mineral occurrences) upper greenschist facies metamorphic rock dominates the Mosquito Creek Formation (AM). These higher grade rocks include mylonite, phyllite, mica schist, and chlorite magnetite schist, as well as mafic and felsic intrusive rocks.

To the north of the Middle Creek Line, the Mosquito Creek Formation (AM) is dominated by poorly sorted wacke-siltstone and wacke-sandstone interbedded with more pelitic rock types ieCoarser grained rock types. The Blue Spec Line (northern set of mineral occurrences) is located about 6 km north of, and parallel to, the Middle Creek Line. The Kurrana Shear Zone defines the southern margin of the belt with granite (Agg).

Blue Spec Mine

Nullagine Mine

Golden Eagle Mine

Blue Spec Line

Mosquito CK Line

Gold Exploration, Nullagine, WA, Australia

MNF Colour Composite Geological Map

Colour Composite Site with Gold Occurences


Northwest Resources PIMA analysis study indicates that the Illite is an Al-rich muscovite (possibly paragonite) and develops proximal to the mineralisation (relatively acid epithermal environments). Chlorite is observed more distal to the mineralisation. These minerals are well represented in the HyMap derived mineralogy.

Also near Nullagine, pyrophyllite is observed in the HyMap mineralogy suggesting the presence of a relatively acid, highertemperature fluid flow zone.

The distribution of the Al-rich white mica is relatively widespread which is presumably related to the porosity / permeability of the Mosquito Creek Belt metasediments to the mineralising fluid (s). The Al-rich white mica is not restricted to the trace of the Blue Spec Line suggesting the potential for mineralisation elsewhere provided suitable structural sites or other focusing mechanism exists.

PIMA studies at Golden Eagle confirm that a muscovite-phengite-chlorite assemblage host the mineralisation

Au mineralisation along the Middle Creek and Blue Spec Lines is localised to structural sites

arising from contrasting competencies between psammite - pelite units during deformation.

Along the Blue Spec Line, hydrothermal alteration mineralogy associated with these structural

sites includes quartz, pyrite, white mica, chlorite and carbonate.

Nullagine Processing: Mineral Maps

Mineral Map Colour Composite Rule Classified Mineral Map


Image depicts the wavelength of the white mica absorption band scaled from 2.185um in blue through to 2.215um absorptions in red ; cool colours represent paragonite, intermediate colours muscovite and warm colours phengite. Mineral occurrences of the Middle Creek and Blue Spec lines are shown.

Changes in Illite (White mica) Al chemistry can vary from paragonite(Al-rich) to muscovite to phengite (Al-poor) are mappable directly with HyMap by tracking the wavelength position of the principal absorption band. The Blue Spec Line is characterised by strongly developed Al-rich white mica. The HyMap derived mineralogy suggests that the Line is continuous from near the Nullagine town ship eastwards.

2.185um 2.215um

Nullagine Processing: White Mica Wavelength Shift


Calcrete Hosted

Yeleerrie, Western Australia, Australia

Langer Heinrich, Namibia

Unconformity Associated

Ranger, Northern Territory, Australia

HyVista HyMap Test Site Surveys: Uranium Deposits


Lake Mason Survey, Yilgarn Region , Western Australia. HyMap Imagery, 4m pixels, Acquired November 2010

Uranium Exploration (Calcrete), Lake Mason, WA, Australia


The Lake Mason U deposit lies 40km to the south west of the Yeelirrie.

The Lake Mason and Yeelirrie lake systems developed during similar climatic conditions over a similar granitoid basement. The Lake Mason palaeodrainage system has uranium channel radiometric data anomalies drilling of which has indentified mineralisation of approximately 1 million tonnes at an average grade of 170ppm uranium.(Source: Prime Minerals Ltd. Website: Www.primeminerals.com.au – 2007)

COLOUR COMPOSITE DCS COLOUR COMPOSITE

Hyperspectral images map regolith and highlight the calcretised paleodrainage.

The mineral maps show that the paleochannels contain calcite, dolomite, Mg-smectite and gypsum.

Dolomite can weather into Mg-smectite, thus the presence of this clay may indicate un-exposed dolomitic calcrete

Lake Mason Processing


Lake Mason Processing: Mineral Ternary Maps


Lake Mason Processing: Mineral Maps


Yeelirrie Survey, Yilgarn Region , Western Australia. HyMap Imagery, 4m pixels, Acquired September 2010

The Yeelirrie Uranium deposit is a carnotite ore body hosted by calcrete located in Cretaceous - Tertiary palaeodrainage channels. The deposit is located towards the northern margin of the Archaean Yilgarn Craton It is the world’s largest surficial uranium deposit with reserves of approximately 50,000tons of U3O8.

The basement to the Yeelirrie palaeochannel is deeply weathered Archaean granitic rock, mainly biotiteadamellite, and presumably the source of the uranium, vanadium, potassium and iron required to form carnotite. The deposit is a horizontal sheet approximately 9 km long and up to 1.5 km wide. The ore body is in 4 meters thick and straddlles the transition between the base of the calcrete profile and the underlying carbonated kaolinite–quartz alluvium.

The carbonate horizon developed by an early replaciveprocess (replacing kaolinite and quartz) to produce friable 'earthy' calcrete which was then altered to a hard, porcellanous calcrete,

The only ore mineral is carnotite, is deposited independently of host lithology, occurring disseminated through seams of 'earthy' calcrete, spheres. The clay rich carbonated rocks of the transition zone at the base of the calcrete profile are an important host.

Uranium Exploration (Calcrete), Yeelirrie, WA, Australia


Uranium Exploration (Calcrete), Yeelirrie, WA, Australia


Rule Classified image summarizing thirteen individual SWIR mineral maps as three (3) “regolith components” coloured as RGB.

Near Mineralisation: Mg Smectite I-II, Saponite, Calcite, Gypsum, Illite-Montmorillonite (2206-2224 nm)

Drainage Channel: Carbonate (Calcite), Saponite, Kaolinite, Illite-Montmorillonite (2206 nm)

Sand Plane: Kaolinite, Carbonate, Illite-Montmorillonite

Yeelirrie Mineral Mapping


Rule Classified image of 8 individual mineral maps highlights mineralogical differences in the palaeodrainage channel and surrounding sand plane. North of the Yeelirrie mineralisation, the channel is depicted by a distinctive ridge / mound pattern typical of valley calcrete and has strong carbonate-saponite (red hues) mineralogy. Presumably the carbonated loam component of the overburden described by Cameron, E., (1990).

South of the mineralisation the channel is less distinctive; the texture is more like the surrounding sand plane. Carbonates (green hues) are abundant in areas but the clay minerals are aluminum rich (Illite, montmorillonite and kaolinite). Presumably the sandy soil / hardpan component of the overburden is dominant here.

The sand plane is dominated by a kaolinite, illite-montmorillonite and / or carbonate assemblage.




The local surficial expression of the palaeodrainage channel hosting the Yeelirrie uranium deposit is mineralogically distinctive. It is unclear whether the observed contrast is due to better exposure (surface disturbance during the evaluation programme; note the drilling pattern visible in the overview colour composite image) and / or some variation in the chemical-physical properties of the environment hosting the ore body.


Uranium Exploration (Calcrete), Langer Heinrich, Namibia

Langer Heinrich Survey, Namibia. HyMap Imagery, 4.6m pixels, Acquired August 2006


COLOUR COMPOSITE

Uranium Exploration (Calcrete), Langer Heinrich, Namibia

MNF COLOUR COMPOSITE


RULE CLASS MINERAL MAP

The boundaries of the mineralized calcrete at Langer Heinrich are shown as white polygons.

The predominant mineral that defines these calcretes is calcite mapped in red. Residual illite

partially covers some of the calcrete and in the eastern most polygon the presence of

dolomite may show a change in calcrete facies. There are areas of calcite that are not

mapped as calcrete, those to the south of the eastern most polygons may be of interest.

Langer Heinrich Processing: Mineral Map


Ranger Survey, Arnhemland, Northern Territory. HyMap Imagery, 5m pixels, Acquired 2005

Uranium Exploration (Unconformity), Ranger, NT, Australia


NATURAL COLOUR COMPOSITE MNF COLOUR COMPOSITE

RANGER MINERALOGY

Footwall sequence comprising a variable mixture metamorphic rocks, which have been chloritised and sericitised.

Lower Mine sequence - interceded carbonates (magenesite to dolomite), schists and cherts. The schist consists of quartz, chlorite and sericite. Below the mineralised zone the carbonate has been silicified to produce a jasperoid chert. Uranium mineralisation in the Lower Mine Sequence is restricted to the zones of chlorite alteration and the schist.

Upper Mine sequence - comprises a thick sequence of quartz-feldspar-biotite schists, micro-gneisses (altered to quartz-chloriteschist) and irregular carbonates. Graphiticschists in the central disturbed zone contain high grade uranium mineralisation.

Hanging wall sequence - a group of micaceous quartz-feldspar schists with intercalated amphibolitic units and garnetiferous horizons.

Intrusives - in the mine area are largely pegmatite and dolerite dykes. The alteration that can be mapped from HyMap data (italics/underlined) are:

Amphibole, Chert, Chlorite, Dolomite, Graphic schist, Magnesite, Sericite (white mica / illite).

Tourmaline occurs within the pegmatitesthat are intruded into the U deposits. Tourmaline (Dravite) is known to be associated with unconformity style U deposits.

Extensive areas of alluvial deposits, green and dry

vegetation occur within the valley around the Ranger

Mine. The black pixels are where vegetation and water

have been masked out the data.

Ranger Processing


Ranger Mineral Mapping

Halloysite (disordered kaolinite) is the dominant mineral in the wider area away from the mine which indicates surficial cover with illite and illite mixed with calcite also occurring in the in these regions.

The dense vegetation and cover in the area limits the extent to which the alteration minerals, chlorite, sericite and tourmaline can be detected from hyperspectral imagery. However, it is possible to distinguish the illite associated with the mineralisation from the back ground, WM2212 (illite) shown in cyan. The presence of this mineral to the south west of the mine area and in the north of the area, as well as localised chlorite occurrences, may be of interest

Ranger Processing: Mineral Maps


In the mine pit there is a clear boundary between chlorite and tourmaline in the SW corner and illites(WM units) in the remainder of the pit.

The illites also show zoning and there are zones of illite mixed with carbonate within the pit. It appears that this illite mixed with carbonate

has been widely distributed around the mine site on haul roads and dumps, though it also occurs in the background of the area. In the SW

corner of the pit the tourmaline bearing pegmatite is highlighted and it is dumps containing this unit that accounts for the tourmaline signature

elsewhere in the mine site.

4 of the 7 minerals reported as associated with the Ranger U deposit have been indentified from the HyMap imagery:

chlorite (Mg), sericite (4 varieties of white mica)tourmaline (dravite and elbaite)dolomite (white mica mixed with carbonate)

Ranger Processing: Mineral Maps


Beltana, South Australia

HyVista HyMap Test Site Surveys: MVT Zinc Deposits


Beltana Mine, South Australia, MVT Zn , 5m pixels, Acquired March 2002

MVT Zinc Exploration: Beltana Mine, South Australia


The geology of the Beltana region

consists of Neoproterozoic Rawnsley

Quartzite and early Cambrian

Parachilna Formation, Woodendinna

Dolomite, Wilkawillina Limestone and

various other shales and limestones.

Zinc mineralisation in the area is

hosted within hematitic dolomite

alteration and breccia of the

surrounding Wilkawillina Limestone.

The main ore mineral is willemite, with

less abundant smithsonite. The zinc

mineralisation is structurally controlled

by the nearby NW Fault.

Alexandria Pengelly & Patrick James, A

In: Roach I.C. ed. 2003. Advances in Regolith, pp. 319-320.

CRC LEMEdvances in Regolith

< Beltana Mine




< Beltana MineThe Beltana mine is located within the Dolomitic unit (PFlr06m), that can be clearly differentiated from the other carbonate units within the area and which contains Hematitic zones (see next slide Pflr08).


Gove, Northern Territory, Australia

HyVista HyMap Test Site Surveys: Bauxite Deposits


Bauxite Exploration: Gove, Northern Territory, Australia


The lateritic bauxites are found mostly in the countries of the tropics and are formed by lateritization of various silicate rocks. In comparison with the iron-rich laterites, the formation of bauxites demands intense weathering conditions in a location with very good drainage. This enables the dissolution of the kaolinite and the precipitation of gibbsite, aluminum hydroxide, the main ore mineral. Zones with highest aluminum content are frequently located below a ferruginous surface layer.

Gibbsite, Kaolinite and Hematite can all be mapped using hyperspectral imagery as is shown in the example from a HyMap survey conducted over the Gove area in the Northern Territory.

SWIR Spectra Well Ordered Kaolinite (Red), Gibbsite (Blue) and the integration of 50% of each one to generate the spectrum Kaol+Gibb (Green).

Mineral Mapping for Bauxite


Natural Colour Composite Image. Red-orange areas show

Hematite soils.

Natural Colour Composite Image vegetation masked out.

Gove Processing


Kaolinite (disordered) Spectrum USGS Lab. Gibbsite Spectrum USGS Lab.

Kaolinite (disordered) Spectrum HyMap Image Gibbsite Spectrum HyMap Image

Gibbsite and Kaolinite: HyMap vs. Lab Spectra


HYMAP SWIR MNF RGB 2-3-4

Areas of kaolinite and gibbsite mapped in red-yellow. Warmer colours indicate higher abundance of hematite

HYMAP HEMATITE ABUNDANCE

Gove Processing: Mineral Maps


HYMAP GIBBSITE ABUNDANCE HYMAP RULE CLASSIFIED MINERAL MAP GIBBSITE AND KAOLINITE

Mineral map derived from spectral classification showing

most abundant occurrences of kaolinite and gibbsite.Warmer colours indicate higher abundance of Gibbsite

Gove Processing: Mineral Maps


Warmer colours indicate higher abundance of Gibbsite.

Note scattering of purple pixels away from mine site-disturbed ground indicating presence of gibbsite at low surface abundance.

Gove Processing: Gibbsite Abundance


Gove Processing: Gibbsite and Kaolinite Abundance


HyVista HyMap Test Site Surveys: Iron Deposits

West Angelas, Western Australia


Iron Exploration: West Angelas, Western Australia


West Angelas: Overview Colour Composite


West Angelas Processing: VNIR MNF RGB 3-4-5


West Angelas Processing: DCS RGB 30-108-115


^ 70> %

West Angelas Processing: MM FeOx 1


^ > 75%

West Angelas Processing: MM Hematite


^ > 24%

West Angelas Processing: MM Goethite


^ 60> %

West Angelas Processing: MM Kaolinite & Muscovite


^ > 85%

West Angelas Processing: MM Dickite


^ 84> %

West Angelas Processing: MM Chlorite


West Angelas Processing: MM RGB Goe-Hem-Epi


West Angelas Processing: MM RC RGB


^0.850UM He 1UM^ Go

West Angelas Processing: MM FeOx WVL


HyMap Hyperspectral Surveys for Mineral Exploration

END

HyVista Corporation

11/10 Gladstone Rd., Castle Hill, NSW, AUSTRALIA

www.hyvista.com

HyMap Hyperspectral Surveys for Mineral Exploration

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