气候变化领域集成服务门户(CCPortal): Regional Moment Tensor Inversion Using Rotational Observations

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DOI	10.1029/2020JB020827
	Regional Moment Tensor Inversion Using Rotational Observations
	Ichinose G.A.; Ford S.R.; Mellors R.J.
发表日期	2021
ISSN	21699313
卷号	126 期号:2
英文摘要	Abstract: There are benefits from the addition of rotational motions to translational displacements for moment tensor (MT) inversions. The rotational radiation pattern is orthogonal to the shear radiation pattern, thus incorporating rotations is equivalent to gaining another observation point on the focal sphere. We demonstrated this by simulating curl and displacement wavefields for a regional distance station. Thus, one 6-C station (3-Component translational + 3-Component rotational) gathers the same information on radiation pattern as two 3-C stations at 90° azimuth from one another along the focal plane axis, which is sometimes difficult to obtain when restricted to surface sensors. We added rotational Green's functions to a regional MT inversion scheme (long-period, time-domain, and linear inversion) by computing spatial gradients from f-κ reflectivity synthetics. For rotational data, we used Array Derived Rotations (ADR) from Piñon Flats Observatory Array and Golay array deployed during IRIS Community Wavefield Demonstration Experiment. The hope is to ultimately use compact and field deployable broadband rotational seismometers instead of ADRs. Rotational motions were predicted from well-constrained deviatoric MT solutions of nine earthquakes recorded by the arrays and other seismic networks. We formed three station sparse datasets with (3-C and 6-C) and without rotational ground motions (3-C only) for eight earthquakes testing the benefits of including rotational waveforms in MT inversions when they are equally weighted with translational waveforms. Adding rotational motions improved the double-couple components and reduced compensated-linear-vector-dipole and isotropic components in full-MT solutions using sparse datasets with poor coverage. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.
英文关键词	Array Derived Rotations; moment-tensor; rotational seismology; seismic arrays
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/187332
作者单位	Lawrence Livermore National Laboratory, Livermore, CA, United States
推荐引用方式 GB/T 7714	Ichinose G.A.,Ford S.R.,Mellors R.J.. Regional Moment Tensor Inversion Using Rotational Observations[J],2021,126(2).
APA	Ichinose G.A.,Ford S.R.,&Mellors R.J..(2021).Regional Moment Tensor Inversion Using Rotational Observations.Journal of Geophysical Research: Solid Earth,126(2).
MLA	Ichinose G.A.,et al."Regional Moment Tensor Inversion Using Rotational Observations".Journal of Geophysical Research: Solid Earth 126.2(2021).