Subsurface Stratigraphy and Structure of the Orakei Korako and Te Kopia Geothermal Systems, New Zealand

Abstract

The Orakeikorako Geothermal System located about 23km NNE of Taupo, New Zealand, on the eastern margin of the Volcanic Centre. The Te Kopia Geothermal System is located a further to the NE,along of the Paeroa Fault Scarp, a major structuralfeature, inferred to be controllingmigration of deep hydrothermal fluids the Orakeikorako- Te Kopia area. Four wells, a distance of 1to apart,have been drilled at and two at Te Kopia, toa maximum depth of They penetrate Pliocene to Quaternary tuffs, rhyolite lava and several ignimbrite sheets. The Mesozoic greywacke basement was not reached. petrographic description of coresand use of point counting techniques has enabled the and differentiation of the Paeroa Ignimbrite,Te Ignimbrite and Akatarewa Ignimbritein the drillholes. Well logs and a panel diagram are presented and were used to describe subsurface stratigraphy and structure in the Kopia area.