Double Difference Earthquake Locations at the Salton Sea Geothermal Reservoir

Boyle, K L ; Hutchings, L J ; Bonner, B P ; Foxall, W ; Kasameyer, P W

关键词: ALGORITHMS;    EARTHQUAKES;    FLUID FLOW;    HYPOCENTERS;    NETWORK ANALYSIS;    PROCESSING;    SALTON SEA;    SALTON SEA GEOTHERMAL FIELD;    SEISMICITY;    WAVE FORMS;   

DOI  :  10.2172/923617
RP-ID  :  UCRL-TR-233538
PID  :  OSTI ID: 923617
Others  :  TRN: US200806%%424

学科分类：地球科学(综合)

美国|英语

来源: SciTech Connect

【 摘 要 】

The purpose of this paper is to report on processing of raw waveform data from 4547 events recorded at 12 stations between 2001 and 2005 by the Salton Sea Geothermal Field (SSGF) seismic network. We identified a central region of the network where vertically elongated distributions of hypocenters have previously been located from regional network analysis. We process the data from the local network by first autopicking first P and S arrivals; second, improving these with hand picks when necessary; then, using cross-correlation to provide very precise P and S relative arrival times. We used the HypoDD earthquake location algorithm to locate the events. We found that the originally elongated distributions of hypocenters became more tightly clustered and extend down the extent of the study volume at 10 Km. However, we found the shapes to depend on choices of location parameters. We speculate that these narrow elongated zones of seismicity may be due to stress release caused by fluid flow.