Triggered crustal earthquake swarm across subduction segment boundary after the 2016 Pedernales, Ecuador megathrust earthquake
Triggered crustal earthquake swarm across subduction segment boundary after the 2016 Pedernales, Ecuador megathrust earthquake
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2016 年厄瓜多尔佩德纳莱斯巨型逆冲地震后引发的跨越俯冲段边界的地壳地震群
DOI：
10.1016/j.epsl.2020.116620
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发表时间：
2021
影响因子：
5.3
通讯作者：
Beck, Susan
中科院分区：
文献类型：
--
作者：
Hoskins, Mariah C.;Meltzer, Anne;Font, Yvonne;Agurto-Detzel, Hans;Vaca, Sandro;Rolandone, Frederique;Nocquet, Jean-Mathieu;Soto-Cordero, Lillian;Stachnik, Joshua C.;Beck, Susan
大型逆冲断层破裂和随后的震后变形引起应力变化，可能会在远离同震破裂区的上板块地壳断层上诱发地震活动。在这项研究中，我们分析了发生在厄瓜多尔北部埃斯梅拉达斯地区的地震群，从2016年厄瓜多尔Mw7.8足目地震后两个月开始。埃斯梅拉达斯地区距离足目破裂区70公里，是俯冲带的一个单独部分。我们表征的埃斯梅拉达斯序列，重新定位的事件使用手动到达时间选择和本地先验的三维速度模型。埃斯梅拉达斯序列的地震位置勾勒出一个上板块断层或剪切带。该序列包含一个大群和几个较小的群。几个事件的矩张量解包括正常和走滑运动和非双力偶分量。在主震群期间，随着时间的推移，地震震源与第一个事件的距离增加，每天几百米的速度，与流体扩散一致。序列内发生波形相似的地震，附近GPS台站的时间序列中出现了与地震活动同时发生的瞬变。波形相似的地震和GPS时间序列中的瞬变现象表明，在该序列中，地壳正断层沿着发生了缓慢的滑动。库仑应力计算显示，在埃斯梅拉达斯地区的正库仑应力变化，与地震活动被触发的足目主震和大余震。地震活动特征表明，在埃斯梅拉达斯地区，地震后的变形包括流体流动和缓慢滑动激活了上板块断层。这些研究结果表明，需要进一步调查浅上板块断层的地震危险潜力和潜在的大逆冲断层地震触发慢滑和浅地震活动的俯冲带的单独部分。
Megathrust ruptures and the ensuing postseismic deformation cause stress changes that may induce seismicity on upper plate crustal faults far from the coseismic rupture area. In this study, we analyze seismic swarms that occurred in the north Ecuador area of Esmeraldas, beginning two months after the 2016 Mw7.8 Pedernales, Ecuador megathrust earthquake. The Esmeraldas region is 70 km from the Pedernales rupture area in a separate segment of the subduction zone. We characterize the Esmeraldas sequence, relocating the events using manual arrival time picks and a local a-priori 3D velocity model. The earthquake locations from the Esmeraldas sequence outline an upper plate fault or shear zone. The sequence contains one major swarm and several smaller swarms. Moment tensor solutions of several events include normal and strike-slip motion and non-double-couple components. During the main swarm, earthquake hypocenters increase in distance from the first event over time, at a rate of a few hundred meters per day, consistent with fluid diffusion. Events with similar waveforms occur within the sequence, and a transient is seen in time series of nearby GPS stations concurrent with the seismicity. The events with similar waveforms and the transient in GPS time series suggest that slow aseismic slip took place along a crustal normal fault during the sequence. Coulomb stress calculations show a positive Coulomb stress change in the Esmeraldas region, consistent with seismicity being triggered by the Pedernales mainshock and large aftershocks. The characteristics of the seismicity indicate that postseismic deformation involving fluid flow and slow slip activated upper plate faults in the Esmeraldas area. These findings suggest the need for further investigation into the seismic hazard potential of shallow upper plate faults and the potential for megathrust earthquakes to trigger slow-slip and shallow seismicity across separate segments of subduction zones.
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影响因子：
3.3
作者：
E. Sokos;J. Zahradník
通讯作者：
E. Sokos;J. Zahradník
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DOI：
--
发表时间：
2013
期刊：
影响因子：
--
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M. Vallée;J. Nocquet;J. Battaglia;Y. Font;M. Segovia;M. Régnier;P. Mothes;P. Jarrín;D. Cisneros;Sandro Vaca;H. Yepes;X. Martin;N. Béthoux;M. Chlieh
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M. Chlieh
影响因子：
2.8
作者：
Font, Yvonne;Segovia, Monica;Theunissen, Thomas
通讯作者：
Theunissen, Thomas
附录：安第斯山脉北部大陆碎片的运动和蠕动俯冲
DOI：
--
发表时间：
2014
期刊：
影响因子：
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J. Nocquet;J. C. Villegas;M. Chlieh;P. Mothes;F. Rolandone;P. Jarrín;D. Cisneros;A. Alvarado;L. Audin;F. Bondoux;X. Martin;Y. Font;M. Régnier;M. Vallée;T. Tran;C. Beauval;J. Mendoza;W. Martinez;H. Tavera;H. Yepes
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3D绝对地震位置最大交会法的改进
DOI：
--
发表时间：
2012
期刊：
影响因子：
--
作者：
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通讯作者：
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