Kawerau geothermal field: Geochemical structure of the reservoir and its response to exploitation

Conference · Wed Dec 31 04:00:00 EST 1997

OSTI ID:602620

Christenson, B W

The Kawerau geothermal field is similar to other gas-rich, high temperature systems found in the Taupo Volcanic Zone of New Zealand. The field is situated over a long-lived volcanic centre, where > km of eruptives, some as young as 2.4 ka, rest unconformably on a Mesozoic greywacke complex. Near-neutral chloride fluids discharge through steeply dipping normal faults in the greywacke into the overlying volcanic units, where they spread laterally through a number of production aquifers. Boiling and dilution are prevalent in both the basement and volcanic units, and these processes significantly affect the chemical characteristics of fluids across the system. Production from the volcanic units has met with pressure draw-down and draw-in of cold recharge fluids, whereas production from the basement structures has been largely stable through time. Production induced boiling has resulted in the development of calcite scale in wellbores and, in some extreme cases, in formation rocks.

• OSTI ID: 602620
• Report Number(s): CONF-971048--
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
58 GEOSCIENCES
GEOCHEMISTRY
GEOTHERMAL ENERGY
GEOTHERMAL RESOURCES
KAWERAU GEOTHERMAL FIELD
NEW ZEALAND
RESERVOIR FLUIDS
RESOURCE DEVELOPMENT