Anisotropic properties in the sedimentary and granite rocks at the Utah FORGE geothermal site revealed by shear-wave splitting of 3-component borehole microseismic data

PreviousNext No AccessSecond International Meeting for Applied Geoscience & EnergyAnisotropic properties in the sedimentary and granite rocks at the Utah FORGE geothermal site revealed by shear-wave splitting of 3-component borehole microseismic dataAuthors: Yingping LiDavid LiLianjie HuangYingcai ZhengPhilip WannamakerJoseph MooreYingping LiBlueSkyDas LLC and University of HoustonSearch for more papers by this author, David LiLos Alamos National LaboratorySearch for more papers by this author, Lianjie HuangLos Alamos National LaboratorySearch for more papers by this author, Yingcai ZhengUniversity of HoustonSearch for more papers by this author, Philip WannamakerUniversity of UtahSearch for more papers by this author, and Joseph MooreUniversity of UtahSearch for more papers by this authorhttps://doi.org/10.1190/image2022-3750065.1 SectionsSupplemental MaterialAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail AbstractCharacterizing geologic formations near a borehole is critically important for the energy and environmental industry. Better understanding anisotropic properties of subsurface formations in a geothermal field is essential for effective fracture stimulation to extract geothermal energy from enhanced geothermal systems. We apply a shear-wave splitting analysis method, based on eigenvector rotation, to six induced micro-earthquakes recorded using a 3-component geophone array deployed in a borehole at the Utah FORGE (Frontier Observatory for Research in Geothermal Energy) site. We determine that the faster S1-wave is along the radial direction at about an azimuth of E12.7oS, while the slower S2-wave is in the tangential direction perpendicular to that of S1-wave. This radial direction is consistent with major-semi axis orientation of induced micro-earthquake distribution. The averaged S-wave splitting rate (SSR) is 0.83%, indicating the average S1-wave velocity is faster than that of S2-wave by 0.83%. Average SSR values for receivers in the sedimentary and granite rocks are 0.91% and 0.72%, respectively, implying that the natural fracture density in the sedimentary rock is higher than that in the granite rocks. We can apply the shear-wave splitting analysis method to induced micro-earthquake data during fracture stimulation for time-lapse monitoring of EGS reservoirs.Keywords: anisotropic, VSP, microseismic, shear wave splitting, borehole seismicPermalink: https://doi.org/10.1190/image2022-3750065.1FiguresReferencesRelatedDetails Second International Meeting for Applied Geoscience & EnergyISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2022 Pages: 3694 publication data© 2022 Published in electronic format with permission by the Society of Exploration Geophysicists and the American Association of Petroleum GeologistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 15 Aug 2022 CITATION INFORMATION Yingping Li, David Li, Lianjie Huang, Yingcai Zheng, Philip Wannamaker, and Joseph Moore, (2022), "Anisotropic properties in the sedimentary and granite rocks at the Utah FORGE geothermal site revealed by shear-wave splitting of 3-component borehole microseismic data," SEG Technical Program Expanded Abstracts : 3619-3623. https://doi.org/10.1190/image2022-3750065.1 Plain-Language Summary KeywordsanisotropicVSPmicroseismicshear wave splittingborehole seismicPDF DownloadLoading ...