As Geothermal Resources Limited announced, the company has conducted temperature gradient drilling at its Frome project in Australia and is providing details on the outcome in a recent release.

According to the announcement, “this drilling has confirmed several important points :

• The geological concept of a buried granitic heat source in the Frome project area is provenby the intersection of granite at 1471 metres depth in Frome 12, some 50 km from thenearest basement granite outcrop. Interpreted comagmatic volcanic rocks of similargeochemical character to the granitic rocks were intersected in Frome 13 at 1703 metres depth.
• In drill core the granite in Frome 12 shows clear evidence of frequent and regular subhorizontal fracturing. Such natural fracturing can potentially be stimulated byhydrofracturing to enhance permeability in the granite.
• Temperatures measured in all drillholes above the granite body clearly indicate above average temperature gradients capable of generating temperatures ofaround 185 to 190°C at 4 km depth.
• The drilling conditions are comparatively straightforward and would appear to present no particular difficulties drilling to greater depths.

Using parameters an Inferred Resource estimate for the thermal energy in place for the defined resource area is 84,000 PJ. The Inferred Resource status reflects the uncertainty concerning how much of this in place thermal energy will ultimately prove to be recoverable. If a conservative heat recovery factor of 20% is applied [based on Tester et al. (2006) then the potentially recoverable thermal energy based on the above Inferred Resource estimate is 16,800 PJ.

Source: Company announcement via The Sydney Morning Herald