| Title | Hydrothermal Mineralization of a Clear Lake Geothermal Well, Lake County, California |
|---|---|
| Authors | Sternfeld, Jeffrey; Keskinen, Mary; Blethen, Richard |
| Year | 1983 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Exploration; USA; California; Lake |
| Abstract | Occidental Geothermal drilled an exploratory well in the Clear Lake volcanic field which penetrated a metasedimentary and metavolanic sequence of Great Valley sequence/Franciscan complex rocks. Fluid entries were encountered at depth. The distribution of hydrothermal mineralization indicates that a shallow recharge zone overlies a deep seated discharge zone. The discharge zone is characterized by the deposition of actinolite, biotite and tourmaline and measured fluid including temperatures of 330-400°C (626-762°F). Superimposed on this mineralization and associated with the fluid entries is vein material characterized by fluid inclusion temperatures of 300-135°C (572-600°F) which probably represents the present geothermal system. |