West Kimberley Metals

West Kimberley Metals is a mineral exploration company that was founded with the intention of discovering major intrusion related gold, and porphyry copper-gold deposits in prospective regions of Eastern Australia and iron oxide copper gold deposits elsewhere. The porphyry copper-gold deposits have been described and studied for decades, since they constituted many of the major sources of copper and gold in the Americas, including over 490 million tonnes of contained copper metal from known resources in the Andeas, with Chilean porphyry deposits alone accounting for up to 40% of the worlds copper production. In contrast, the intrusion related gold deposits and iron oxide copper gold deposits have only emerged as major exploration targets in the last 30 years.  Australia has produced the largest IOCG discovery, the giant Olympic Dam deposit (7.8bt at 0.9% Cu, 0.3g/t Au. 0.3%U3O8) in South Australia. Other examples are Ernest Henry north of Cloncurry (167mt @1.1%Cu, 0.54g/t Au) and Prominent Hill (102mt @1.5%Cu, 0.5g/t Au, 3.2g/t Ag) in South Australia.  The South Australian and Queensland IOCG discoveries spurred exploration for this class of ore deposit, but the search for porphyry copper gold and intrustion related gold deposits appears to have lagged in Australia, although several discoveries have been made.  Exploration focused specifically on finding porphyry copper gold deposits in the 1980's by the Peko Wallsend Company (Peko) resulted in the discovery of Northparkes and Lake Cowal deposits, and Newcrest discovered the Cadia, Ridgeway, and more recently, the giant Cadia East porphyry copper gold deposits. The remarkably successful search philosophy used by Peko is well known, but strangely few other companies applied this approach in the last three decades.  Barriers to discovery for these classes of deposits in Australia may be related to mindset or aversion to risk, and the fact that new discoveries are likely to be concealed beneath substantial cover, and therefore targets are likely to be expensive to test. 

 

Target Style	Example	Location	Resource
	Ernest Henry	Isa Eastern Succession, QLD	167Mt @ 1.1% Cu, 0.54g/t Au
IOCG	Prominent Hill	Gawler Craton, SA	102Mt@ 1.5% Cu, 0.5g/t Au
	Olympic Dam	Roxby Downs, SA	7.8Bt @ 0.9% Cu, 0.3g/t Au and 0.3% U3O8
	Kidston	North Queensland	> 3Moz Au historic production
IRGS	Mt. Leyshon	North Queensland	> 3Moz Au historic production
	Pogo	Tintina Gold Belt, Alaska	> 5.6Moz Au
	Red Dome /Mungana	North Queensland	> 3Moz Au eq. historic and current resources
PCG	Cadia/Ridgeway	Orange District, NSW	> 55Moz Au eq.
	Northparkes	Goonumbla District, NSW	> 100Mt @ ~1% Cu, ~0.5g/t Au

WKM's mineral deposit target styles with notable examples

Until Northparkes was discovered, there was general view that porphyry copper/gold deposits would not be found in Australia because most of the porphyry type deposits elsewhere in the world occur in rocks much younger than those found in Australia.  This ignored the fact that rock suites that typically host porphyry style deposits are preserved especially in the Palaeozoic and possibly Mesozoic rocks of Eastern Australia.  Peko proved this view to be wrong, but the exploration community took little notice.  With the exception of Kidston and Mt Leyshon, the above discoveries were made "under cover", that is, the deposits were not exposed at the surface, but were concealed beneath younger rocks or sediment.  Bold exploration, based on interpretation of geophysical data, geological surmise and a willingness to drill deep holes based on flimsy evidence, led to most of the discoveries.  In some instances the deposits are so large that the application of innovative technologies of scale enabled reduction of the mining and milling costs associated with exploitation of the deposits to very competitive low levels.  The scale of these types of deposit is such that their production typically spans one or more metal price cycles, and there will therefore be one or more periods when they will be producing in a high metal-price regime.

Apart from the promise of size and grade of these types of deposit, two other factors have combined to lead WKM to focus on exploration for them.  Firstly the geological understanding of their genesis and geophysical signatures has been greatly advanced largely by university research.  Secondly in the last 30 years State and Federal Governments have invested very large sums of money to acquire new, high quality geophysical data to encourage further exploration.  Much of this new data was acquired during a very trying period for mineral exploration globally, from 1996 to 2003, when low metal prices caused a substantial downturn in exploration especially amongst the so-called junior exploration companies.  As a consequence WKM considers that the new data has even now been under-utilised.  There has been a substantial upturn in exploration funding since 2003, however much of the focus has been on areas of known surface mineralisation, and this has become a highly competitive business.  In reviewing opportunities for new discovery, WKM came to the conclusion that the opportunities to discover again "under cover", more truly world class deposits of the types listed above had received much less attention in the current exploration boom.   It appeared that there was an opportunity to acquire highly attractive prospects using the modern geophysical data as a basis for target selection.     Furthermore, since the discoveries made a decade or more ago, there have been significant advances in geophysics and geochemistry that enable target selection under cover with greater confidence. 

WKM has used its expertise to identify several attractive new gold and copper/gold targets in terrains that have had little or no previous exploration.  West Kimberley Metals invites investors to subscribe funds that will be used in a highly focused exploration of the targets using sophisticated techniques to explore under cover. WKM has technical strengths and backgrounds in interpretation of aeromagnetic data, pole-dipole induced polarization (3DIP), structural geology, economic/exploration geochemistry and conceptualisation, coupled with extensive experience in exploration management.  Importantly its people have a record of mineral discovery. The WKM exploration group brings these strengths together to form a well balanced management framework from which efficient and effective methods are employed to make significant mineral discoveries. Together with a direct focus on particular gold deposit styles, WKM plans a conscious and direct endeavor to concentrate on the discovery of  "world class deposits", defined here as those containing greater than 3 million ounces of economic gold or gold equivalent. WKM believes that with a firm understanding of the genetic processes leading to the deposition of mineral deposits, generally, larger deposits have much larger 'footprints' that may be identified by explorationists employing the correct concepts and criteria.

WKM has constructed a number of geological and exploration models for the mineral deposit styles of interest.  Within Queensland, the key exploration models are as follows:

Iron-Oxide Copper Gold Deposits (IOCG)

IOCG deposits are characterised by an association of significant Iron Oxide material (Magnetite or Hematite, or most commonly both), with Copper and Gold. These deposits formed as a consequence of a protracted magmatic-hydrothermal history of metal deposition, scavenging    and remobilization. Mineralisation is generally structurally controlled, and the presence of substantial mafic magmatic material, either locally or at depth, is considered by WKM to be a crucial aspect to the genesis of these deposits.
IOCG deposits occur in the Mesoproterzoic Mount Isa Eastern Succession, host to the Ernest Henry, Osborne and Selwyn-Starra IOCGs.  Recent geological work by WKM   has indicated the potential for IOCG's in a number of other provinces of North Queensland. Specifically, the research pinpointed the covered areas beneath a part of the Carpentaria Basin (unexposed Yambo Subprovince, Etheridge Province) to be highly prospective for these deposits. WKM's Walsh project covers this prospective area.

Key exploration criteria for the discovery of IOCG's in the Walsh project area include: the presence of magnetic highs sitting coincident to the edges of gravity highs, generally on NW to N trending structures. Unlike the Mount Isa Eastern Succession, the Walsh project area has undergone significant subsequent geological modification since potential IOCGs were emplaced. This means that the original geophysical features associated with the deposits may have been partially modified, especially if they were emplaced on major structures that were reactivated during later geological epochs (Siluro-Devonian and Permo-Carboniferous). An example of the disturbance of the original geophysical features may include the modification of magnetic and gravity high signatures if abundant later granitic materials (and associated hydrothermal fluids) was intruded locally.

 

Magnetic Profile (Reduced to Pole [RTP]) over the Ernest Henry IOCG deposit, characterized by an intense magnetic high in profile. Profile is 10km long in an east-west direction. MGA94 Zone 54.

Intrusion Related Gold Systems (IRGS)

Intrusion Related Gold Systems are among the most gold endowed mineral systems within Eastern Australia, and include multi-million ounces gold deposits such as Kidston and Mount Leyshon in North Queensland. Globally, they account for a significant portion of economic gold mineralization, and include the Pogo (Alaska, >5Moz Au) and Fort Knox (Alaska, >5Moz) deposits of the Tintina Gold Belt of Northern America. IRGS are characterized by a diverse range of mineralization styles, including, but not limited to, disseminated gold in granite (Timbarra, NSW), Breccia-hosted (Mount Leyshon and Kidston, North QLD) and narrow- and network- vein hosted (Lake Cowal).  In Queensland, these deposits were emplaced during the Permo-Carboniferous period, and quite often have an association with tin-tungsten provinces.

WKM have recently identified a NW-NNW trending corridor of Permo-Carbonifeous gold mineralization that extends from Cracow in the south, and up through WKM's Walsh project, over 1000km to the north. Within this corridor are a number of significant Permo-Carboniferous intrusion related and epithermal gold deposits, including, among others, Pajingo (Epithermal, >3.5Moz Au, the Wirralie-Yandan-Mt.Coolan gold district (Epithemal, >2Moz Au), Mount Leyshon, andthe Poison Lake Breccia Pipe systems (north of Greenvale, Moggie Mining Ltd.)

WKM considers this zone highly prospective for IRGS, and have drawn geological and metallogenic analogies with the heavily gold enriched Tintina Belt of North America. This zone is broadly encompassed within the Permo-Carboniferous Kennedy Igneous Province of Queensland, but is slightly more defined in terms of the prospectivity for gold mineralization. WKM's QGP1, QGP2 and QGP3 project areas, in addition to the Walsh Project area, cover high mineral potential areas within this mineralized corridor, specifically focused on the discovery of Intrusion Related Gold Systems.

Key exploration criteria for the discovery of these systems in the Walsh, QGP1, QGP2 and QGP3 project areas include: the presence of discrete intense magnetic lows, sitting on the peripheries of buried plutons.  Quite often this is represented in magnetic images as not only discrete lows, but intense magnetic lows within a broader area of magnetic low response.  Proximity to either major NW-NNW trending structures, NE trending structures, or more explicitly, the intersection of these structures, is considered important. Magnetic lows represent the presence of magnetite/pyrrhotite, which although are strongly magnetic minerals, were emplaced during the magnetic reversal period of the Permo-Carboniferous, so that they are expressed as low magnetic signatures.  K/Th ratio radiometric analysis is also used to discriminate areas that have undergone hydrothermal alteration associated with mineral deposition, in areas not under cover.

 

Magnetic Profile (Reduced to Pole [RTP]) over the Poison Lake M Breccia Pipe (Moggie Mining Ltd.), interpreted to be an IRGS deposit, characterized by an intense magnetic low in profile. Profile is 2km long in an east-west direction. MGA94 Zone 55.

Porphyry Copper-Gold Systems (PCG)

Porphyry Copper-Gold systems, although related to the Intrusion Related Gold  family of mineral deposits, differ slightly in their genesis, but quite often share the same geological and geophysical attributes.  Porphyry systems are found all over the world, and Eastern Australia hosts several world class examples, including Cadia-Ridgeway and Northparkes (NSW, combined >7Moz Au, 1Mt contained Cu), and Red Dome/Mungana (QLD, >2Mt Au). Numerous large Porphyry deposits occur in Chile, Argentina and Brazil, some of which are the largest copper deposits on earth, containing in excess of 6Bt of mineralized material. Porphyry deposits are characterized by economic mineralization hosted within veins, structures and shear zones in and around a large hydrothermal alteration system proximal to the tops of buried subvolcanic intrusions. Within Queensland, a number of geological provinces host mineralized porphyry systems, and of the most interest to WKM are those of the Townsville-Mornington Island Igneous belt, extending from Townsville through to Cape York.  Red Dome and Mungana, in the Chillagoe mining district, with a combined historic and current gold resource in excess of 2Moz, are typical examples of the type of porphyry systems of interest to WKM. These deposits are also of Permo-Carboniferous age.

Recent analysis and interpretation of government geophysical datasets (aeromagnetics and gravity) has led WKM to conclude that the intrusive systems related to porphyry mineralization in the Chillagoe district continue under cover out to the WNW, forming another focus of interest for WKM in the Walsh Project area. Key targeting criteria for Porphyry systems within the Walsh Project area are similar for those of Intrusion Related Gold Systems, except that NW structures become more significant, and the recognition of spatially broader hydrothermal alteration and surface geochemical systems that accompany porphyry deposits.

 

Magnetic Profile (Reduced to Pole [RTP]) over the Mungana Porphyry-Au deposit, characterized by an intense magnetic low in profile. Profile is 2km long in an east-west direction. MGA94 Zone 55.

WKM's Target Key Selection Criteria
	Geological	Late stage Permo-Carboniferous felsic intrusions or breccia pipes, generally intruding slightly older felsic intrusions, on NW, NNW or NE trending structures.
IRGS	Geophysical	Discrete aeromagnetic lows, occasionally sitting within or at the periphery of broader magnetic lows. K/Th Radiometric highs.
	Geochemical	Au-Bi-W-Sn-Sb-Ag-Mo (or combination thereof) surface geochemical signature, generally detached from base metal signatures (Cu, Pb, Zn)
	Geological	Major NNE to NW trending structures/lineaments. Presence of abundant mafic material. Lower to upper amphibolite facies metamorphic rocks.
IOCG	Geophysical	Aeromagnetic highs, occasionally near the edges of large gravity highs. N to NW trending magnetic lineaments.
	Geochemical	Cu-Ni-Co-Au-Zn-Pb surface geochemical signatures.
	Geological	Recognition of porphyry type alteration zones. NW to NE trending structures. Buried or exposed porphyritic rhyolitic and dacitic units.
PCG	Geophysical	Deep aeromagnetic lows, either broad or discrete, sitting within or at the edges of large scale gravity lows. K/Th Radiometric highs.
	Geochemical	Similar to IRGS, but more specifically, Au-Cu-Mo-Zn-Pb-Ag surface geochemical signature.