The Whangairorohea Geothermal Field

Abstract

Whangairorohea is an important geothermal prospect situated between Ohaaki-Broadlands to the east and Ngatamariki to the west. It is characterised by a broadly shaped moderate resistivity anomaly, the presence of several hot springs, widespread sporadic silicification, and probably a hydrothermal eruption crater. Exploitation induced gravity changes at Ohaaki-Broadlands during the period 1967-1974 have propagated to within at least 1 km of the Whangairorohea springs suggesting that there is, indeed, a body of hot wafer underlying the area and which has been drawn upon as a result of pressure reduction at Ohaaki. There is a very strong likelihood that there is a significant, but as yet undetected, thermal flux from this system that enters directly into the Waikato River which bisects the prospect. The Whangairorohea system is presently poorly recognised and is in need of further investigation.