Annual Report EL 25338 Burt Plain for the period 8 January 2007 to 7 January 2008 Year 1

Abstract

The Exploration Licence was held by A W Mackie until it was acquired by Western Desert Resources Ltd in May 2007. The tenement covers the prospective combined magnetic/gravity anomalies at the Capricorn Prospect.The tenement is located within the Arunta Block of Palaeoproterozoic to Mesoproterozoic age. The block consists of meta-igneous and metasedimentary rocks which have been strongly deformed and metamorphosed up to granulite facies.The project area is underlain by highgrade metamorphic rocks of the Strangways Metamorphic Complex, which forms part of the Central Province of the Arunta Block. These rocks are exposed in the north eastern part of the area and crop out intermittently in the western portion of the licence. Much of the tenement is covered by up to 120m of Recent to Tertiary sediments.The tenement is characterised by a major coincident magnetic and gravity anomaly which has been called the Capricorn prospect. The gravity data show a bouguer anomaly with an amplitude of 11 milligals which is associated with an aeromagnetic anomaly of greater than 5,000nT.Western Desert Resources (WDR) undertook a gravity traverse with a station spacing of 200m over the Capricorn Prospect in 2006. The survey followed the Stuart Highway and delineated a bouguer anomaly with an amplitude of 11 mgal coincident with the aeromgnetic anomaly. In 2007 WDR completed a gravity survey over the Capricorn Prospect during August and September; Daishsat Pty Ltd undertook the work. The gravity survey limits were from 327800E to 381000E and 7414200N to 7419000N. The nominal grid spacing was 200x200 metres. Three lines of detailed infill were completed with 25m station spacing. A total of 1,082 stations were surveyed. The gravity stations were located using a realtime kinematic Leica GPS unit with an accuracy of better than 1 cm for easting, northing and elevation. The basestation from the 2006 gravity survey was used for control.Gravity readings were acquired using a Scintrex CG5 automated gravity meter. The readings were processed and reduced using Geosoft GRAVRED software to Bouguer anomaly. WDR completed an IP survey over parts of the Capricorn Prospect during July and August 2007; Search Exploration Pty Ltd undertook the work. Six Dipole- Dipole (DD) Induced Polarisation traverses totalling 29.4 line kilometres were completed. All of the traverses were undertaken in a north-south orientation. Five of the lines were collected using a 200m transmitter dipole with 200m receiver dipoles and 200m station spacing. For one of the traverses a trial using a 400m transmitter dipole with 200m receiver dipoles was undertaken. The data was collected using Search Exploration proprietary developed full time series Induced Polarisation Acquisition unit (SSIP16). Some advantages of collecting full time series data are that long wavelength telluric noise and SP drift are easily identifiedand removed. Additionally the receiver unit has low internal noise levels (relevant to industry standards) enabling the collection with confidence of low amplitude signal (i.e. 1msec levels). The unit has multiple input channels (42) allowing the simultaneous collection of data to greater dipoles (depth). Five holes were drilled on various gravity, magnetic and IP anomalies within the Capricorn Prospect on EL 25338. A total of 1832.5 metres of diamond drilling was completed. The work commenced on 25th October and was completed on 17th November. All of the holes were vertical. Magnetic susceptibility and specific gravity measurements were taken at regular intervals. The radioactivity of the core was checked with a scintillometer - no anomalous values were found. The drill core was cut in half and sections of the cut-core were submitted to ALS Chemex for analysis for 51 elements by ICPMS (ME-MS41 method) following an aqua regia digest. The bouguer gravity results show that the bodies causing the magnetic anomalies are denser than the surrounding rocks. The data and resultant models for the six Induced Polarisation traverses show a strongly chargeable body on traverse 374800E at 7413250N. This chargeable feature is highly correlated with some strong high resistivity legs. The observed chargeability anomaly extends to n =1 indicating that the source is most likely in contact with the overburden and the resistivity data and subsequent modelling indicates that the overburden is very shallow in this area and some of the basement may be faulted up. The stacked model display enables the continuity of the sources to be observed. It shows how there is an expression of the highly chargeable body on line 374800E at 7413250N on line 375600E. The stacked model display also shows how this chargeable body correlates with the highly resistive body that appears to be faulted and shallowing in the location of the chargeable body.The five diamond drill holes completed in 2007 were designed to test magnetic, gravity and induced polarisation targets. All of the holes intersected a similar suite of basic gneissic rocks probably originally derived from gabbros. The rocks were characterised by a high magnetite content ranging from about 5-15%. Pyrite was encountered in most of the holes. The presence of magnetite and pyrite explains the geophysical anomalies. Drill core samples from the holes were analysed for a suite of elements. The results show enrichment in vanadium with weak associated cobalt, nickel and barium values. It is postulated that the vanadium is associated with the magnetite present in the holes. Vanidiferous magnetite occurs in many gabbroic bodies worldwide and is mined in South Africa and Russia. Similar mineralisation occurs in the Windimurra deposit in Western Australia.