TY  - JOUR
ID  - epos1835
UR  - http://doi.org/10.1002/grl.50438
IS  - 11
A1  - Martinez-Garzon, Patricia
A1  - Bohnhoff, Marco
A1  - Kwiatek, Grzegorz
A1  - Dresen, Georg
Y1  - 2013///
N2  - Studyingvariationsofthestress?eldinreservoirscaused by massive ?uid 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 ?eld, 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
PB  - American Geophysical Union
JF  - Geophysical Research Letters
VL  - 40
SN  - 0094-8276
TI  - Stress tensor changes related to fluid injection at The Geysers geothermal field, California
SP  - 2596
AV  - none
EP  - 2601
ER  -