Moment tensors of induced microearthquakes in The Geysers geothermal reservoir from broadband seismic recordings: Implications for faulting regime, stress tensor, and fluid pressure.

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F18%3A00494895" target="_blank" >RIV/67985530:_____/18:00494895 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1029/2018JB016251" target="_blank" >http://dx.doi.org/10.1029/2018JB016251</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2018JB016251" target="_blank" >10.1029/2018JB016251</a>

Result language

angličtina

Original language name

Moment tensors of induced microearthquakes in The Geysers geothermal reservoir from broadband seismic recordings: Implications for faulting regime, stress tensor, and fluid pressure.

Original language description

Full moment tensors of 1,421 microearthquakes in The Geysers geothermal field were calculated using waveform data from a field-wide broadband network and the approach based on the principal component analysis. Spatial characteristics of faulting regime, stress tensor and the isotropic component (ISO) of moment tensors were investigated. The studied events form different clusters dominated by normal faults (NF) and strike-slip (SS) faults, respectively. The SS-dominated clusters are related to the SS stress state observed in the southwestern side of the field where two NW-SE trending fault zones exist. Increasing proportions of SS faults were observed near the shallow and deep parts of the NF-dominated clusters. Temperature differences between the upper and lower parts of the reservoir do not change the overall stress states of clusters. The stress ratios in the NW part are much smaller than in the SE part of the field. The retrieved ISOs range between -5% and 25% for 96% of events. The average percentages of positive ISOs are correlated with the average injection rates in different clusters, and keep an increasing trend with depth below the main injection interval. Only 10% of events show negative ISO and are mainly constrained within the depth range of steam extraction. The proportion of events with negative ISO suggests much weaker seismic responses of the steam extraction than the water injection. The spatial variations of the ISO percentage do not follow the seismicity variations as the ISO is more sensitive to the pressure changes related to the fluid injection and migration.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10507 - Volcanology

Project

<a href="/en/project/GC16-19751J" target="_blank" >GC16-19751J: Seismic anisotropy and attenuation retrieved from acoustic emissions and observations of natural and induced seismicity</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Geophysical Research: Solid Earth

ISSN

2169-9313

e-ISSN

—

Volume of the periodical

123

Issue of the periodical within the volume

10

Country of publishing house

US - UNITED STATES

Number of pages

19

Pages from-to

8748-8766

UT code for WoS article

000451086200025

EID of the result in the Scopus database

2-s2.0-85054487624