TY  - CONF
ID  - epos1970
UR  - http://meetingorganizer.copernicus.org/EGU2017/EGU2017-2804.pdf
A1  - Leptokaropoulos, Konstantinos Michail
A1  - Staszek, Monika
A1  - Lasocki, Stanislaw
A1  - Kwiatek, Grzegorz
A1  - Martinez-Garzon, Patricia
Y1  - 2017/04//
N2  - The rising needs for energy along with the recent requirements for more ef?cient usage and exploitation of the
deep underground have resulted to a growing scienti?c and public concern on related environmental impacts.
Hydraulic fracturing that has been carried out during the last decades is occasionally connected with triggered
and induced seismicity worldwide. Data from geothermal ?elds can be used as a proxy for shale gas exploitation
associated seismicity since they are both tightly connected to hydraulic fracturing. For that reason we utilize
?The Geysers? data from the compiled SHEER (Shale Gas Exploration and Exploitation Induced Risks) database.
The Geysers (California, USA) is the largest producing geothermal ?eld in the world and has been suf?ciently
monitored and studied since the last decades. Seismic and technological data gathered during the past ?40 years
indicate a connection of seismic activity with the ?uctuations of the injected ?uid volume. In this study we verify
and quantify this correlation by analyzing the data associated with 2 injection wells (Prati-9 and Prati-29) which
covers a time period of approximately 7 years (from November 2007 to August 2014). The correlation between
spatio-temporal seismicity evolution and variation of the injection data is performed by elaboration of original and
smoothed time-series through speci?ed statistical tools (cross correlation, binomial test to investigate signi?cant
rate changes, b-value variation). Our analysis indicate a short time delay of seismicity occurrence at distances
larger than 200m from the injection well, whereas no evidence of signi?cant correlation between injection rates
and b-values was discovered. The obtained results are expected to contribute to a better comprehension of the role
of hydraulic fracturing and the physical processes controlling seismogenesis in ?uid injection sites.

Acknowledgements:
This work was supported within SHEER: "Shale Gas Exploration and Exploitation Induced Risks" project funded
from Horizon 2020 ? R&I Framework Programme, call H2020-LCE-2014-1 and within statutory activities
No3841/E-41/S/2016 of Ministry of Science and Higher Education of Poland.
TI  - Space-Time Evolution of Seismicity in North-Western Geysers
Geothermal Field and its Connection to Stimulation Processes
M2  - Vienna, Austria
AV  - public
T2  - EGU General Assembly 2017
ER  -