Geothermal Potential of East Timor

Abstract

Geologically, Timor is situated in the collision zone between the Banda volcanic arc and the Australian continental margin. The volcanism associated with this collision zone forms the Inner Banda Arc, 100 km to the north of East Timor. On mainland East Timor, there has not been any recent active volcanism and there is no evidence for any intrusive magmatism. Geologically therefore, there is little expectation that magmatically-heated, high temperature geothermal systems will be found here.

The hot springs on mainland East Timor are dilute, alkaline, sodium-bicarbonate waters with variable chloride up to 540 mg/kg and a maximum temperature is 62?C. The composition suggests they are deeply circulating meteoric waters that have encountered temperatures up to 100?C.

Hot springs on Atauro island (25 km from the mainland) have temperatures up to 70?C and a thermally altered seawater source. Unlike the mainland, there is evidence here for recent volcanism and possibly a higher-temperature, magmatic-related geothermal system.