Granite A Hot Prospect
Newcastle Herald
Friday September 5, 2008
A STUDY of the Earth's gravity field across 23,000 square kilometres is understood to have detected granite several kilometres underground in the Upper Hunter that could be used to generate pollution-free electricity known as hot rock or geothermal energy.
The just-completed $480,000 eight-week study by the NSW Primary Industries Department covered an area from Camberwell, up the North Coast to Bundarra, west to Wee Waa, south to Gulgong and back east to Camberwell.Details of the investigation, scheduled to be made public within four months, are yet to be analysed and compiled into a three-dimensional computer-based map.Departmental spokeswoman Jenny Ward said the presence of large granite bodies in the surveyed area, if confirmed, might provoke interest as sources for geothermal energy. However, this would require further investigation.Gas, petroleum and geothermal exploration companies, rather than the department, would have to investigate.The State Government has been interested in the Hunter's geothermal potential for more than a decade.The technology involves pumping water down to the hot subterranean rocks and using the steam produced by the process to drive electricity-generating turbines.The latest gravity study aimed to collect precise measurements of the Earth's gravity field by updating information gathered about 40 years ago from tests undertaken 11 kilometres apart.The latest project involved about 6000 measurements being taken two kilometres apart.The tests detected the shape, depth and density of rocks down to about five kilometres and also provided information on geological faults.Similar tests have recently been done west of Bourke, west of Hay and on the South Coast, near Braidwood.
© 2008 Newcastle Herald