Magnetic Study of the Mokai Geothermal Field

Abstract

A low level airborne magnetic survey taltitucis 7 6 5 , a.s.1.. mean nominal neignt above terrain: 3 G O m) over the Mokai aeothsrmai field and the surrounding arsa has deline3ted an area oi relatively low total force maunetic anomaly associated with the geothermal field. This low magnetic anomaly appsars to be ths sifect of a hydrothermally demaunetized body Gf volcanic rocks within the Mokai reservoir at depths of about 0 to - 500 m a.s.1. The Pukemoremore rhyolite dome lyinu directly to the east of the Mokai geothermal field is also demagnetized. It is possible that part of the Mokai reservoir extends further to the east beneath the Pukemoremore dome.