Probing earthquake triggering and source processes through multiscale analyses of induced seismicity
报告人（单位）
Dr. Xiaowei Chen（University of Oklahoma）
报告时间
2022年3月9日(周三) 8:00
主办方
International Professionals for the Advancement of Chinese Earth Sciences 中国地球科学促进会
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报告人介绍
Dr. Chen obtained her bachelor’s degree in 2007 in Geosciences at the University of Science and Technology of China (USTC). Later, she went to University of California, San Diego (UCSD) to continue her graduate research in Geophysics and completed her Ph. D in 2013. Dr. Chen has been in Earthquake Research Institute (ERI) at the University of Tokyo and in Woods Hole Oceanographic Institution as Postdoctoral researcher. Now, being Wagner Associate Professor and Presidential Professor at the University of Oklahoma, Xiaowei and her group use a variety of seismological methods to analyze earthquakes source spectra and catalogs. They aim to address earthquakes interaction, earthquakes responses to anthropogenic and natural stress perturbations, the rupture process of earthquakes, and what controls the maximum size expected of the earthquake on individual faults? She is currently working on analyzing induced seismicity in the central US, geothermal induced seismicity in California, source parameter validations and dense arrays for sub-surface imaging.
报告摘要
In the past decade, the seismicity rate in Oklahoma experienced rise, peak, and decline as a result of varying industry operations. This large-scale “unintentional” earthquake experiment provided us with rich datasets to future probe earthquake triggering and source processes. In this presentation, I present multi-scale analyses of induced seismicity in Oklahoma by combining several studies, and their implications for better understanding of earthquake processes in different tectonic settings.
Spatiotemporal patterns of seismicity at regional scale shows systematic regional variations of hydraulic properties of the Arbuckle Group within different pressure units. Spatiotemporal patterns of seismicity within individual sequences exhibit similar behaviors with natural earthquake swarms in tectonically active regions.
Systematic large-scale analyses of stress state show that a majority of reactivated seismogenic faults are optimally oriented. However, detailed analyses of stress state evolutions within representative sequences reveal diverse fault planes distributions within swarm-type sequences, and that fault architecture influences sequence evolutions.
Focusing on the well-recorded sequence Guthrie sequence in central Oklahoma, diverse triggering mechanisms including aseismic slip, fluid and earthquake interactions are observed. The largest event in this sequence shows considerable rupture complexity using finite slip inversion methods. Comparison with slip inversions for earthquakes in different tectonic regions indicates that the level of complexity is similar to earthquakes in low deformation rate regions, suggesting fault characteristics control rupture patterns.