| Title | Investigation of the Seismic Wave Velocities at The Geysers Geothermal Field, California |
|---|---|
| Authors | Gupta, Harsh K.; Tzeu-Lie Lin; Ward, Ronald W. |
| Year | 1980 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Exploration; USA; California; The Geysers; Geophysical Surveys; P Wave; S Wave; Poissons Ratio |
| Abstract | Preliminary results are presented of a detailed analysis of P- and S-waves recorded at a number of USGS operated seismic station in the vicinity of the Geysers Geothermal Field, California from nearby shallow focus earthquakes. P and S-phases are recognized on seismograms and convincingly traced with distance on record sections. Average regional velocities in the upper crust are estimated to be 5.39 km/sec and 2.93 km/sec respectively for the P- and S-waves. Poisson's ratio is estimated for a number of locations using Wadati diagrams and are found to vary from 0.13 to 0.32. In general, they are found to be lower at the locations close to the steam production zones at the Geysers. |