气候变化领域集成服务门户(CCPortal): Analysis of Fault Zone Resonance Modes Recorded by a Dense Seismic Array Across the San Jacinto Fault Zone at Blackburn Saddle

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DOI	10.1029/2020JB019756
	Analysis of Fault Zone Resonance Modes Recorded by a Dense Seismic Array Across the San Jacinto Fault Zone at Blackburn Saddle
	Qiu H.; Allam A.A.; Lin F.-C.; Ben-Zion Y.
发表日期	2020
ISSN	21699313
卷号	125 期号:10
英文摘要	We present observations and modeling of spatial eigen-functions of resonating waves within fault zone waveguide, using data recorded on a dense seismic array across the San Jacinto Fault Zone (SJFZ) in southern California. The array consists of 5-Hz geophones that cross the SJFZ with ~10–30 m spacing at the Blackburn Saddle near the Hemet Stepover. Wavefield snapshots after the S wave arrival are consistent for more than 50 near-fault events, suggesting that this pattern is controlled by the fault zone structure rather than source properties. Data from example event with high signal to noise ratio show three main frequency peaks at ~1.3, ~2.0, and ~2.8 Hz in the amplitude spectra of resonance waves averaged over stations near the fault. The data are modeled with analytical expressions for eigen-functions of resonance waves in a low-velocity layer (fault zone) between two quarter-spaces. Using a grid search-based method, we investigate the possible width of the waveguide, location within the array, and shear wave velocities of the media that fit well the resonance signal at ~1.3 Hz. The results indicate a ~300 m wide damaged fault zone layer with ~65% S wave velocity reduction compared to the host rock. The SW edge of the low-velocity zone is near the mapped fault surface trace, indicating that the damage zone is asymmetrically located at the regionally faster NE crustal block. The imaging resolution of the fault zone structure can be improved by modeling fault zone resonance modes and trapped waves together. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	crustal imaging; dynamics and mechanics of faulting; guided waves; transform faults; wave propagation
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187557
作者单位	Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX, United States; Department of Geology and Geophysics, The University of Utah, Salt Lake City, UT, United States; Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan; Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States; Southern California Earthquake Center, University of Southern California, Los Angeles, CA, United States
推荐引用方式 GB/T 7714	Qiu H.,Allam A.A.,Lin F.-C.,et al. Analysis of Fault Zone Resonance Modes Recorded by a Dense Seismic Array Across the San Jacinto Fault Zone at Blackburn Saddle[J],2020,125(10).
APA	Qiu H.,Allam A.A.,Lin F.-C.,&Ben-Zion Y..(2020).Analysis of Fault Zone Resonance Modes Recorded by a Dense Seismic Array Across the San Jacinto Fault Zone at Blackburn Saddle.Journal of Geophysical Research: Solid Earth,125(10).
MLA	Qiu H.,et al."Analysis of Fault Zone Resonance Modes Recorded by a Dense Seismic Array Across the San Jacinto Fault Zone at Blackburn Saddle".Journal of Geophysical Research: Solid Earth 125.10(2020).