气候变化领域集成服务门户(CCPortal): Resolvability of the Centroid-Moment-Tensors for Shallow Seismic Sources and Improvements From Modeling High-Frequency Waveforms

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DOI	10.1029/2020JB019643
	Resolvability of the Centroid-Moment-Tensors for Shallow Seismic Sources and Improvements From Modeling High-Frequency Waveforms
	Hejrani B.; Tkalčić H.
发表日期	2020
ISSN	21699313
卷号	125 期号:7
英文摘要	Shallow earthquakes in the depth range 0–30 km make up more than 60% of all world's earthquakes. However, resolving their seismic source parameters such as the depth and moment tensor components presents a challenge. Here, we investigate the effect of frequencies higher than 0.025 Hz on centroid-moment-tensor inversion for the earthquakes occurring in the top 10 km of the Earth's crust. For a synthetic source located at the depth of 1 km, the maximum amplitude of ground motion due to a vertical dip-slip mechanism from the waveforms filtered at 0.01–0.15 Hz is about 1,400 times larger than that filtered at 0.01–0.025 Hz. We quantify the effect of this dramatic difference and other waveform differences by introducing the “balance of amplitudes” and “waveform similarity” functions for different depths and frequencies. They present a simple and fast way to estimate the resolvability of seismic sources at a given depth and frequency band. For the 20 May 2016, Mw = 5.9 Petermann Ranges earthquake in Central Australia analyzed at 0.01–0.025 Hz, a high uncertainty accompanies the estimated source parameters. When the frequency band is 0.01–0.15 Hz, the centroid depth is well constrained at 1 km and the mechanism is a thrust fault striking ~314°N and dipping ~30°NE. These simulations require accurate Earth models. Our result, obtained at higher frequencies, is in a great agreement with various other studies that have been carried out for this earthquake and confirms a 20-km long, shallow rupture. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Centroid-moment-tensor; Petermann Ranges earthquake; Resolution matrix; Seismic source uncertainties; Shallow earthquakes; Waveform modeling
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/187752
作者单位	Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory, Australia
推荐引用方式 GB/T 7714	Hejrani B.,Tkalčić H.. Resolvability of the Centroid-Moment-Tensors for Shallow Seismic Sources and Improvements From Modeling High-Frequency Waveforms[J],2020,125(7).
APA	Hejrani B.,&Tkalčić H..(2020).Resolvability of the Centroid-Moment-Tensors for Shallow Seismic Sources and Improvements From Modeling High-Frequency Waveforms.Journal of Geophysical Research: Solid Earth,125(7).
MLA	Hejrani B.,et al."Resolvability of the Centroid-Moment-Tensors for Shallow Seismic Sources and Improvements From Modeling High-Frequency Waveforms".Journal of Geophysical Research: Solid Earth 125.7(2020).