TY  - JOUR
ID  - epos1994
UR  - https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2017GL073929
IS  - 14
A1  - Staszek, Monika
A1  - Orlecka-Sikora, Beata
A1  - Leptokaropoulos, Konstantinos Michail
A1  - Kwiatek, Grzegorz
A1  - Martinez-Garzon, Patricia
Y1  - 2017/07//
N2  - We use a high-quality data set from the NW part of The Geysers geothermal ?eld to determine
statistical signi?cance of temporal static stress drop variations and their relation to injection rate changes.
We use a group of 322 seismic events which occurred in the proximity of Prati-9 and Prati-29 injection wells to
examine the in?uence of parameters such as moment magnitude, focal mechanism, hypocentral depth, and
normalized hypocentral distances from open-hole sections of injection wells on static stress drop changes.
Our results indicate that (1) static stress drop variations in time are statistically signi?cant, (2) statistically
signi?cant static stress drop changes are inversely related to injection rate ?uctuations. Therefore, it is highly
expected that static stress drop of seismic events is in?uenced by pore pressure in underground ?uid
injection conditions and depends on the effective normal stress and strength of the medium.
PB  - Geophysical Research Letters
JF  - Geophysical Research Letters
VL  - 44
SN  - 00948276
TI  - Temporal static stress drop variations due to injection activity at The Geysers geothermal field, California
SP  - 7168
AV  - none
EP  - 7176
ER  -