Core Holes At Long Valley Caldera Geothermal Area (Benoit, 1984)
Exploration Activity: Core Holes At Long Valley Caldera Geothermal Area (Benoit, 1984)
|Exploration Activity Details|
|Location||Long Valley Caldera Geothermal Area|
|Exploration Technique||Core Holes|
|Activity Date||1982 - 1982|
Several core holes were also drilled in the caldera's west moat by Phillips Petroleum Company in 1982, including:
- PLV-1, drilled to approximately 711 m depth
- PLV-2, drilled to approximately 640 m depth.
The PLV-1 and PLV-2 wells represent some of the first intermediate-depth holes drilled into the caldera's west moat and provide temperature, lithologic, and geochemical data for this area that were previously unavailable. The maximum temperature encountered in PLV-1 was about 125°C and about 50°C in PLV-2. Temperature gradients in both wells were favorable; however, the shallow depths of these wells prohibit accurate prediction of reservoir temperatures with increased depth below the west moat. Assuming no temperature reversal were to occur beneath the west moat and gradients remain consistent with depth, reservoir temperatures of 218-288°C in the Bishop Tuff or early rhyolite were predicted for PLV-1, consistent with chemical geothermometer temperature estimates for the hole.
- Walter R. Benoit (1984) Initial Results from Drillholes PLV-1 and PLV-2 in the Western Moat of the Long Valley Caldera
- Michael L. Sorey (1985) Present State of the Hydrothermal System in Long Valley Caldera, California