A review of the Kawerau Geothermal Field, New Zealand

Deep hot water (>300 °C), sourced in the south, moves across and flows north into the field, through faults and fractures in otherwise impermeable basement greywacke into the overlying volcano-sedimentary sequence. The hot fluids spread laterally into permeable zones along sub-horizontal volcanic and sedimentary layers, with lacustrine sediments, and welded intervals within some ignimbrite units, acting as localised aquitards.