气候变化领域集成服务门户(CCPortal): Seismotectonics and Fault Geometries of the 2019 Ridgecrest Sequence: Insight From Aftershock Moment Tensor Catalog Using 3-D Green's Functions

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DOI	10.1029/2020JB019577
	Seismotectonics and Fault Geometries of the 2019 Ridgecrest Sequence: Insight From Aftershock Moment Tensor Catalog Using 3-D Green's Functions
	Wang X.; Zhan Z.
发表日期	2020
ISSN	21699313
卷号	125 期号:5
英文摘要	The 2019 Mw 7.1 Ridgecrest earthquake occurred on 6 July, preceded by the Mw 6.4 foreshock on 4 July 2019. These two earthquakes occurred close in space and time with partially overlapping surface ruptures and aftershock patterns, raising the question of the relationship between the two events. Geological surveys and satellite observations provide important constraints on the surface traces of faulting. However, the subsurface fault geometries, which are important for understanding the regional stress field, earthquake initiation, propagation, and termination, are not well resolved. In this study, moment tensor solutions for 256 earthquakes in the 2019 Ridgecrest sequence were determined by waveform inversion using 3-D velocity model. The obtained moment tensor solutions show rotations of the stresses after mainshock, indicating the ratio of mainshock stress drop to the background stress to be 0.5–0.9. The obtained moment tensor catalog also facilitates a better understanding of the subsurface fault geometries, including (1) splay faults and antithetic faults in the northwest aftershock zone; (2) shallow flower structures near the Mw 7.1 epicenter; and (3) subparallel faults in the southeast aftershock zone. The aftershocks' studies suggest the very complex surface ruptures near the 2019 Ridgecrest Mw 7.1 epicenter are near-surface features that linked to a simple large throughgoing fault at >5 km depth. We also found that the southeastern-most aftershocks, which are located less than a kilometer from the Garlock fault trace, have significant different strike directions from that of the Garlock fault, indicating the central Garlock fault remains seismically quiet. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	3D velocity model; Dynamic overshoot; Fault geometries; Moment tensor inversion; Ridgecrest; Stress rotation
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/187857
作者单位	Seismological Laboratory, California Institute of Technology, Pasadena, CA, United States
推荐引用方式 GB/T 7714	Wang X.,Zhan Z.. Seismotectonics and Fault Geometries of the 2019 Ridgecrest Sequence: Insight From Aftershock Moment Tensor Catalog Using 3-D Green's Functions[J],2020,125(5).
APA	Wang X.,&Zhan Z..(2020).Seismotectonics and Fault Geometries of the 2019 Ridgecrest Sequence: Insight From Aftershock Moment Tensor Catalog Using 3-D Green's Functions.Journal of Geophysical Research: Solid Earth,125(5).
MLA	Wang X.,et al."Seismotectonics and Fault Geometries of the 2019 Ridgecrest Sequence: Insight From Aftershock Moment Tensor Catalog Using 3-D Green's Functions".Journal of Geophysical Research: Solid Earth 125.5(2020).