The geophysical expression of the deposit is a large magnetic low, thought to be due to the hydrothermal breccia with a more discrete DIP resistivity high trending N-S over Area 3 that extends into 309 South. A negative chargeability response over the deposit is interpreted to be due to either severe EM coupling or current channelling which may occur at the contact between the siliceous breccia and more conductive carbonaceous material in unsilicified breccia and sediments.
Exploration during 2006 concentrated on extending resources at 309 and culminated in the drilling of approximately 20 holes for 7,500m, 70% of which was diamond core. The program tested for depth and strike extensions to Area 2.
The best results for the program were reported to the east of Areas 1 and 3. High grade intercepts including 35m @ 5.61g/t Au (with a higher grade section of 18m @ 9.9g/t Au) from 133 meters in drill hole THRCD894 and 18m @ 2.15g/t Au from 132 meters in drill hole THRCD895 were recorded immediately east and down plunge of Area 1. In addition, hole THRCD895 intersected 19m @ 5.30g/t from 215 meters depth (including 5m @ 14.3g/t Au in a lower zone which probably represents the down plunge extension of Area 3 mineralisation. The drilling indicates that the Area 2 structure does not extend east of 4900E.
Infill drilling at 40m centres around these holes reported results of lower tenor, suggesting more complex geology and a relatively small resource potential. Further infill drilling is needed at 20x 20m centres to define an inferred resource and most of this drilling was to be undertaken from underground as directional control from surface is problematic. The drilling also showed that the prospective silicified breccia did not extend beyond 5100E. Deeper drilling is recommended to the south of THRCD894 and 895 on lines 4960E and 5040E as the silicified breccia (potential brittle host) is still open to the south.
Three deep 80m spaced holes (THRCD 891, 892 and 893) were drilled to test the down dip extensions of Area 2 and reached a maximum depth of 591m. The drilling was designed to intersect the sub vertical projection of Area 2 at between 60m and 100m down dip from the deepest resource intercepts on respective sections. The holes intersected widely developed silica +/- pyrite altered sediments in the projected positions with minor breccia (10 to 20m) intersected in THRCD 892. Gold grades are all less than 0.1g/t. Broad low grade intercepts in THRCD 892 and 893 (to 13m @ 2.4g/t Au) are situated 40 to 60m south of Area 2, in the hanging wall and may be related to southerly plunges of the Area 1 structure. A high grade intercept near the base of THRCD 891 (4m @ 10.4g/t Au from 552m) is believed to represent a narrow sub-parallel splay some 50m to the north of the Area 2 structure. The intercept includes 1m @36g/t Au with coarse gold in a kaolinite bearing fracture. None of these intersections have been followed up.
The figure below shows the drilling completed in 2006.
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