Shear‐wave splitting and fracture alignments at the Northwest Geysers, California
作者： M. Lou , E. Shalev , P. E. Malin
DOI: 10.1029/97GL01845
关键词:
摘要: Shear-wave splitting is commonly observed on three-component microearthquake seismograms recorded at the Northwest Geysers geothermal field, California. The polarization of leading shear waves around each recording station predominantly N10°–40°E, suggesting that shear-wave caused mainly by pervasive, north-northeast orientated anisotropy. Time delays between and second can be as large 10ms/km to 30ms/km. We propose direction magnitude this wave due presence stress-aligned secondary fractures related several northwest-trending, right-lateral faults in area.
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