National Research Center for Integrated Natural Disaster Management, Santiago, Chile.
Departamento de Ciencias Geológicas, Universidad Católica del Norte, Antofagasta, Chile.
Sci Rep. 2019 Mar 13;9(1):4403. doi: 10.1038/s41598-019-40282-6.
We performed an integrated analysis of the coseismic slip, afterslip and aftershock activity of the 2014 M 8.1 Pisagua earthquake. This earthquake seems to be spatially located between two major historical earthquakes, the 1868 M 8.8 earthquake in southern Peru and the 1877 M 8.5 earthquake in northern Chile. Continuous GPS data were used to model the coseismic slip of the mainshock and the largest aftershock (M 7.6). The afterslip was modeled for 273 days (end of year 2014) after the largest aftershock, revealing two patches of afterslip: a southern patch between the mainshock and the largest aftershock and a patch to the north of the mainshock. Observations from the seismic network indicate that aftershocks were concentrated near the southern patch. Conversely, the northern patch contained hardly any aftershocks, indicating a dominant aseismic slip. The Pisagua earthquake occurred within a prominent, curved section of the Andean subduction zone. This section may have acted as a barrier for the largest historical earthquakes and as an isolated segment during the Pisagua earthquake.
我们对 2014 年皮萨瓜 8.1 级地震的同震滑动、余滑和余震活动进行了综合分析。这次地震似乎位于秘鲁南部 1868 年 8.8 级地震和智利北部 1877 年 8.5 级地震这两次主要历史地震之间。我们利用连续 GPS 数据对主震和最大余震（M7.6）的同震滑动进行了建模。在最大余震发生 273 天后（2014 年末）对余滑进行了建模，揭示了两个余滑区：主震和最大余震之间的南部余滑区和主震以北的余滑区。地震网络的观测结果表明，余震集中在南部余滑区附近。相反，北部余滑区几乎没有余震，表明以非弹性滑动为主。皮萨瓜地震发生在安第斯俯冲带一个显著的、弯曲的地段。该地段可能是最大历史地震的屏障，也是皮萨瓜地震中的一个孤立段。
