eprintid: 1970
rev_number: 21
eprint_status: archive
userid: 10
dir: disk0/00/00/19/70
datestamp: 2017-06-27 09:33:54
lastmod: 2017-09-19 09:55:33
status_changed: 2017-09-19 09:55:33
type: conference_item
metadata_visibility: show
creators_name: Leptokaropoulos, Konstantinos Michail
creators_name: Staszek, Monika
creators_name: Lasocki, Stanislaw
creators_name: Kwiatek, Grzegorz
creators_name: Martinez-Garzon, Patricia
creators_id: kleptoka@igf.edu.pl
creators_id: mstaszek@igf.edu.pl
creators_id: lasocki@igf.edu.pl
creators_id: kwiatek@gfz-potsdam.de
creators_id: 
corp_creators: Institute of Geophysics, Polish Academy of Sciences, Seismology, Warsaw, Poland
corp_creators: Institute of Geophysics, Polish Academy of Sciences, Seismology, Warsaw, Poland
corp_creators: Institute of Geophysics, Polish Academy of Sciences, Seismology, Warsaw, Poland
corp_creators: Helmholtz-Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam, Germany
corp_creators: Helmholtz-Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam, Germany
title: Space-Time Evolution of Seismicity in North-Western Geysers
Geothermal Field and its Connection to Stimulation Processes
subjects: MP2
subjects: RU1_1
subjects: SG
divisions: SHEER-5
full_text_status: public
pres_type: poster
abstract: The rising needs for energy along with the recent requirements for more efficient usage and exploitation of the
deep underground have resulted to a growing scientific 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 fields 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 field in the world and has been sufficiently
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 fluctuations of the injected fluid 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 specified statistical tools (cross correlation, binomial test to investigate significant
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 significant 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 fluid 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.
date: 2017-04
date_type: published
event_title: EGU General Assembly 2017
event_location: Vienna, Austria
event_dates: 23–28 April 2017
event_type: conference
official_url: http://meetingorganizer.copernicus.org/EGU2017/EGU2017-2804.pdf
access_IS-EPOS: limited
owner: Publisher
citation:   Leptokaropoulos, Konstantinos Michail and Staszek, Monika and Lasocki, Stanislaw and Kwiatek, Grzegorz and Martinez-Garzon, Patricia  (2017) Space-Time Evolution of Seismicity in North-Western Geysers Geothermal Field and its Connection to Stimulation Processes.  In: EGU General Assembly 2017, 23–28 April 2017, Vienna, Austria.     
document_url: https://episodesplatform.eu/eprints/1970/7/Leptokaropoulos_et_al_2017_Space-Time_Evolution_of_Seismicity_in_NW_Geysers_Geothermal_Field_and_its_Connection_to_Stimulation_Processes_Poster.pdf