气候变化领域集成服务门户(CCPortal): Earthquake Swarm Detection Along the Hikurangi Trench, New Zealand: Insights Into the Relationship Between Seismicity and Slow Slip Events

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DOI	10.1029/2020JB020618
	Earthquake Swarm Detection Along the Hikurangi Trench, New Zealand: Insights Into the Relationship Between Seismicity and Slow Slip Events
	Nishikawa T.; Nishimura T.; Okada Y.
发表日期	2021
ISSN	21699313
卷号	126 期号:4
英文摘要	Earthquake swarms, which are anomalous increases in the seismicity rate without a distinguishable mainshock, often accompany transient aseismic processes, such as fluid migration and episodic aseismic slip along faults. Investigations of earthquake swarm activity can provide insights into the causal relationship between aseismic processes and seismicity. Slow slip events (SSEs) along the plate interface in the Hikurangi Trench, New Zealand, are often accompanied by intensive earthquake swarms. However, the detailed spatiotemporal distribution of these earthquake swarms is still unclear. Here, we use the epidemic-type aftershock-sequence (ETAS) model to detect earthquake swarms (M ≥ 3) and create a new earthquake swarm catalog (1997–2015) along the Hikurangi Trench. We compare the earthquake swarm catalog with Global Navigation Satellite System (GNSS) time series data, and existing SSE and tectonic tremor catalogs. Most of the detected (119) earthquake swarm sequences were intraplate events, and their epicenters were mainly concentrated along the east coast of the North Island, whereas many tectonic tremors were located inland. Twenty-five of the detected earthquake swarms occurred within 25 days before and after transient eastward GNSS displacements due to known or newly detected SSEs. We find that the earthquake swarms sometimes preceded the GNSS displacements by more than several days. SSE-induced stress loading is therefore not a plausible triggering mechanism for these pre-SSE earthquake swarms. We propose that high fluid pressure within the slab, which accumulated before the SSEs, may have caused intraplate fluid migration, which in turn triggered the pre-SSE earthquake swarms. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	crustal fluid; earthquake swarm; seismicity; slow slip event; subduction zone; tectonic tremor
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/187192
作者单位	Disaster Prevention Research Institute, Kyoto University, Kyoto, Japan; Graduate School of Science, Kyoto University, Kyoto, Japan
推荐引用方式 GB/T 7714	Nishikawa T.,Nishimura T.,Okada Y.. Earthquake Swarm Detection Along the Hikurangi Trench, New Zealand: Insights Into the Relationship Between Seismicity and Slow Slip Events[J],2021,126(4).
APA	Nishikawa T.,Nishimura T.,&Okada Y..(2021).Earthquake Swarm Detection Along the Hikurangi Trench, New Zealand: Insights Into the Relationship Between Seismicity and Slow Slip Events.Journal of Geophysical Research: Solid Earth,126(4).
MLA	Nishikawa T.,et al."Earthquake Swarm Detection Along the Hikurangi Trench, New Zealand: Insights Into the Relationship Between Seismicity and Slow Slip Events".Journal of Geophysical Research: Solid Earth 126.4(2021).