@article{epos1994,
          volume = {44},
          number = {14},
           month = {July},
          author = {Monika Staszek and Beata Orlecka-Sikora and Konstantinos Michail Leptokaropoulos and Grzegorz Kwiatek and Patricia Martinez-Garzon},
           title = {Temporal static stress drop variations due to injection activity at The Geysers geothermal field, California},
       publisher = {Geophysical Research Letters},
            year = {2017},
         journal = {Geophysical Research Letters},
           pages = {7168--7176},
             url = {https://episodesplatform.eu/eprints/1994/},
        abstract = {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.}
}