| Title | The Effects of Pressure, Temperature and Lithology on Seismic Wave Velocities for Rocks from the Larderello Geothermal Field |
|---|---|
| Authors | Bruno Tarquini, Mauro Cameli, Claudio Donati and Randolph J. Martin III |
| Year | 1995 |
| Conference | World Geothermal Congress |
| Keywords | seismic velocity, seismic attenuation, rock properties, laboratory study |
| Abstract | A suite of laboratory measurements were performed on oriented low porosity metamorphic rock cores recovered from several geothermal wells near Larderello. Compressional and shear wave velocities were measured as a function of orientation with respect to the foliation, effective confining pressure, and temperature. Seismic wave attenuation was computed for several data sets. Permeability was measured on the rocks from one well. All the rocks were slightly anisotropic, less than 15% in general. Seismic wave velocities exhibited a small pressure dependence. Even at the water-steam transition the change in velocity was less than 1.5%. All the data suggests that the rocks contain few microcracks and the anisotropy is, for the most part, due to mineral orientation. |