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EL40/2008 East Lisle is located about 30km northeast of Launceston in north-east Tasmania. It covers part of the historical Lisle Goldfield, and lies 25km from the Warrentinna project area, and only 45 kilometres from the Beaconsfield gold mine.
The Lisle Goldfield is reputed to have produced 250,000 ounces of gold from alluvial workings. There was a thriving community here and production was mostly prior to 1900. Lisle is the second largest goldfield in eastern Tasmania, behind Beaconsfield.
The regional geology of north east Tasmania is dominated by Pre-Carboniferous rocks of the Mathinna Group comprising Silurian-Devonian sequences of micaceous quartzwackes and interbedded mudstones, intruded by late Devonian granitoids. These granitoids are responsible for the extensive tin and gold mineralisation of the district.
The East Lisle tenement is situated on the western edge of the Scottsdale granite batholith which intruded the Mathinna Group rocks. The Scottsdale Batholith is part of a granitic intrusive complex covering 550 square kilometres. The granitoids at Lisle are highly weathered and so generally do not crop out, and are covered by scree and alluvium derived from prominent topographic high outcrops of contact-metamorphosed Mathinna group sedimentary rocks.
The bulk of the gold in the Lisle region was won from alluvial deposits. There seems to be a strong association between gold and the granitoid-sedimentary rock contact, however no bedrock source for the gold has ever been found. The extensive scree and alluvium in the area presumably covers this source.
The Lisle area has been only patchily explored by various companies since the early 1970s with limited success. Almost no bedrock drill testing has been done. The bedrock source of the 250,000 ounces of gold remains open to speculation, however Greatland has preliminary compilations and models which suggest that a major source of lode and disseminated style mineralisation - merely covered in thin scree, and readily open pittable and thus potentially very profitable - can be found with systematic modern exploration techniques.
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