Geothermal systems in the Taupo volcanic zone

Most of the Waikato region’s geothermal resource is actually underground. The geothermal activity we can see on the Earth’s surface is much more restricted in size and distribution. One way of determining the extent of geothermal systems is by measuring the ground’s electrical resistivity.

This map shows the geothermal systems in the Taupo Volcanic Zone as they are defined by electrical resistivity. Find out more about resistivity.

Resistivity is a measure of the ground’s ability to conduct electricity. Generally, geothermal water has lower resistance (conducts electricity better) than normal ground water.

• Low resistivity (red) indicates the presence of geothermal water.
• High resistivity (purple) indicates normal ground water, soil and rock.