Tamar Geothermal
NE Tasmania has some of the highest heat flow values in Australia. This is due to it being under laid by granite rocks which retain a significant amount of retained geothermal heat.
This heat has the potential to be tapped to generate base load electricity.
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Devonport Natural Hydrogen and Helium Project
A large sedimentary basin exists through the central part of Tasmania and this strikes NNW-SSE. Sediments within this basin appear to have trapped migrating hydrogen and helium.
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Presence of H2 is likely related to a thick section of thrusted E. Cambrian ultrabasic ophiolite complexes which underlay the central and western parts of the island which are undergoing a seperentization reaction occurring and expelling gas.
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Helium is most likely generated by Devonian aged granodiorite plutons in the sub-surface undergoing radioactive decay.
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The presence of both Helium and Hydrogen gas in both Jericho-1 and Shittam-1 wells suggests these gases are migrating up soling thrust faults which break back down into the ultramafics and granodiorites.
Rawlinson et al., 2010. Structure of the Tasmanian lithosphere from 3D seismic tomography Australian Journal of Earth Sciences - AUST J EARTH SCI
3D model shows the extent of outcropping and concealed allochtonous E. Cambrian ultramafic-mafic complexes underlaying central and southern part of Tasmania.
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Central area with Tasmania Basin of most interest, but thick coverage of Jurassic Dolerites obscures surface expression.
Early Cambrian (Toyonian) thrusted Ultramafic units appear to be the H2 source rock and gas migrating up thrust faults
Several stratigraphic wells drilled in the Tasmania Basin in the south of the country intersected Permian sedimentary sequences which contained H2 & He gases. These units were capped by thick Jurassic aged Dolerite seals.
Source: 2006, MRT. Geological Survey Bull 72. The geology and Mineral Deposits of Tasmania; a summary