eprintid: 1817 rev_number: 11 eprint_status: archive userid: 6 dir: disk0/00/00/18/17 datestamp: 2017-02-09 11:03:12 lastmod: 2017-05-16 12:12:57 status_changed: 2017-02-09 11:03:12 type: article metadata_visibility: show creators_name: Boyd, O. Sierra creators_name: Dreger, Douglas S. creators_name: Lai, Voon Hui creators_name: Gritto, Roland corp_creators: California Institute of Technology, Seismological Laboratory, California title: A Systematic Analysis of Seismic Moment Tensor at The Geysers Geothermal Field, California subjects: MP1 subjects: RU1_1 subjects: SG divisions: SHEER-5 full_text_status: none abstract: The Geysers geothermal field is one of the most seismically active regionsinnorthernCalifornia.Mostoftheeventsoccuratshallowdepthsandarerelated tostressandhydrologicalperturbationsduetoenergyproductionoperations.Tobetter understand the relationships between seismicity and operations, better source mechanism information is needed. Seismic moment tensors offer insight into the nature of equivalent forces causing the seismicity. Fifty-three M>3 events located at The Geysers geothermal field were selected from the University of California Berkeley Moment Tensor Catalog for analysis of seismic moment tensor solutions and associated uncertainties. Deviatoric and full moment tensor solutions were computed, and statistical tests were employed to assess solution stability, resolution, and significance.Inthisstudy,weexamineseveralsourcemodelsincludingdouble-couple(DC), pure isotropic (ISO; volumetric change), and volume-compensated linear vector dipole (CLVD) sources, as well as compound sources such as DC�CLVD, DC�ISO, and shear–tensile sources. In general, wefind from a systematic approach toward characterizing uncertainties in moment tensor solutions that The Geysers earthquakes, as a population, deviate significantly from northern California seismicity in terms of apparent volumetric source terms and complexity. date: 2015 date_type: published publication: Bulletin of the Seismological Society of America volume: 105 number: 6 publisher: Seismological Society of America pagerange: 2969-2986 id_number: doi:10.1785/0120140285 issn: 0037-1106 official_url: http://doi.org/10.1785/0120140285 access_IS-EPOS: limited owner: Publisher citation: Boyd, O. Sierra and Dreger, Douglas S. and Lai, Voon Hui and Gritto, Roland (2015) A Systematic Analysis of Seismic Moment Tensor at The Geysers Geothermal Field, California. Bulletin of the Seismological Society of America, 105 (6). pp. 2969-2986. DOI: https://doi.org/10.1785/0120140285