TY - JOUR ID - epos1929 UR - http://doi.org/10.1002/2016GL070145 IS - 16 A1 - Martinez-Garzon, Patricia A1 - Vavrycuk, Vaclav A1 - Kwiatek, Grzegorz A1 - Bohnhoff, Marco Y1 - 2016/08// N2 - We investigate the sensitivity of stress inversion from focal mechanisms to pore pressure changes. Synthetic tests reveal that pore pressure variations can cause apparent changes in the retrieved stress ratio R relating the magnitude of the intermediate principal stress with respect to the maximum and minimum principal stresses. Pore pressure and retrieved R are negatively correlated when R is low (R??0.6. This observation is independent of faulting style, and it may be related to different performance of the fault plane selection criterion and variability in orientation of activated faults under different pore pressures. Our findings from synthetic data are supported by results obtained from induced seismicity at The Geysers geothermal field. Therefore, the retrieved stress ratio variations can be utilized for monitoring pore pressure changes at seismogenic depth in stress domains with overall low R. PB - American Geophysical Union JF - Geophysical Research Letters VL - 43 SN - 0094-8276 TI - Sensitivity of stress inversion of focal mechanisms to pore pressure changes SP - 8441 AV - none EP - 8450 ER -