eprintid: 1835 rev_number: 15 eprint_status: archive userid: 6 dir: disk0/00/00/18/35 datestamp: 2017-03-02 10:28:04 lastmod: 2017-05-16 12:35:34 status_changed: 2017-03-02 10:28:04 type: article metadata_visibility: show creators_name: Martinez-Garzon, Patricia creators_name: Bohnhoff, Marco creators_name: Kwiatek, Grzegorz creators_name: Dresen, Georg corp_creators: Geomechanics and Rheology, GFZ German Research for Geosciences,Germany. corp_creators: Geomechanics and Rheology, GFZ German Research for Geosciences,Germany; Free University Berlin, Institute of Geological Sciences, Berlin, Germany.. corp_creators: Geomechanics and Rheology, GFZ German Research for Geosciences,Germany. corp_creators: Geomechanics and Rheology, GFZ German Research for Geosciences,Germany. title: Stress tensor changes related to fluid injection at The Geysers geothermal field, California subjects: MP6_2 subjects: MP6_3 subjects: RU1_1 subjects: SG divisions: IP13 full_text_status: none abstract: Studyingvariationsofthestressfieldinreservoirscaused by massive fluid injection is important toward an improved understanding of geomechanical processes involved. We report on spatio-temporal variations of the local stress tensor orientation at The Geysers geothermal field, California. We apply two stress inversion methods with detailed uncertainty assessments using a selection of events recorded between 2007 and 2012. Our results clearly indicate variations in the orientation of the principal stress axes for the reservoir as a whole showing a normal faulting regime at the reservoir depth between 2 and 3.7km bounded by a strike-slip regime above and below. Analyzing the temporal evolution of the stress tensor orientation for a prominent seismicity cluster we observe a clear correlation of changes in orientation for s1–3 with the highest injection rates. These results suggest that temporal changes in the stress tensor orientation could contribute to characterize reservoirs during stimulation date: 2013 date_type: published publication: Geophysical Research Letters volume: 40 number: 11 publisher: American Geophysical Union pagerange: 2596-2601 id_number: doi:10.1002/grl.50438 issn: 0094-8276 official_url: http://doi.org/10.1002/grl.50438 access_IS-EPOS: limited owner: Publisher citation: Martinez-Garzon, Patricia and Bohnhoff, Marco and Kwiatek, Grzegorz and Dresen, Georg (2013) Stress tensor changes related to fluid injection at The Geysers geothermal field, California. Geophysical Research Letters, 40 (11). pp. 2596-2601. DOI: https://doi.org/10.1002/grl.50438