| Title | RESULTS OF GEOTHERMAL SURFACE EXPLORATION ON THE ISLAND OF GRANDE COMORE, UNION OF COMOROS |
|---|---|
| Authors | J. Brotheridge, O. Benavente, J. Charroy, I. Bogie, C. Mohamed, N. Houmadi |
| Year | 2015 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | Grande Comore, Comoros, Karthala, Rift. |
| Abstract | Geothermal surface exploration has been conducted on the island of Grande Comore, Union of Comoros. This included geochemical gas and liquid sampling and analysis. A CO2 flux survey was also undertaken. Geophysical surveys include gravity and magnetotellurics, although only preliminary results of the latter are available at the time of paper submission. Thermal features are found in the caldera at the summit of the active Karlatha volcano and in a rift to the north of the caldera. There is little geochemical or geophysical evidence for an exploitable resource within the caldera. However, the northward rift contains a solfatara which has fumaroles with gas chemistry indicative of a high temperature (300°C) potential resource. The resistivity pattern at depth beneath the solfatara is consistent with the possibility of a resource a depth. As Grande Comore is a hot spot volcanic island the potential resource there may be analogous to the Puna development in Hawaii. Early power estimates of 48 MWe are adequate for the planned initial development of 10 MWe. |