| Title | The Tongariro Geothermal System (New Zealand): Review of Geophysical Data |
|---|---|
| Authors | F.D. Walsh, M.P. Hochstein and C.J. Bromley: |
| Year | 1998 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | |
| Abstract | A review of geophysical data collected over the Tongariro geothermal prospect since 1974 is presented. Interpretation shows that the resistivity structure and hydrological setting of the Tongariro geothermal system have close to those of a vapourdominated system. Its vapourdominated reservoir is capped by a coherent, c. 200 to 300 m thick condensate layer containing altered rocks with low resistivity. All active are to a c. large area underlain the part this layer. The heat discharged by all manifestations amounts to c. 58 of which most (c. 44 is released by the Ketetahi fumarole field. Four earthquake swarms since 1985 had epicentres close to the Te Mari Craters, where volcanic activity occurred last The isotopic characteristics of discharged steam and the recent history of volcanic eruptions can be used to the Tongariro prospect as a volcanic geothermal system. |