Rupture Process of the 2020 Caribbean Earthquake Along the Oriente Transform Fault, Involving Supershear Rupture and Geometric Complexity of Fault
Rupture Process of the 2020 Caribbean Earthquake Along the Oriente Transform Fault, Involving Supershear Rupture and Geometric Complexity of Fault
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2020 年加勒比地震沿 Oriente 转换断层的破裂过程，涉及超剪切破裂和断层的几何复杂性
DOI：
10.1029/2020gl090899
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发表时间：
2021
影响因子：
5.2
通讯作者：
Yamashita Shinji
中科院分区：
文献类型：
--
作者：
Tadapansawut Tira;Okuwaki Ryo;Yagi Yuji;Yamashita Shinji
2020年1月28日，加勒比海发生了一次大的走滑地震。我们利用一种新的反演方法，反演了地震的远震波形，构建了一个有限断层模型，同时解析了断层几何形状和滑动的时空演变。该模型显示，从震中向西沿300公里的Oriente转换断层段几乎是单边的破裂传播，其中两次破裂的速度超过了当地的横波速度。我们的模型表明，2020年加勒比海地震破裂遇到了与震源区域附近的测深特征相关的断层系统弯曲。断层系统的几何复杂性引发了多次破裂事件和复杂的破裂演化。我们对地震的分析揭示了破裂过程的复杂性和断层几何形状，这是以前未被认识到的海洋转换断层，被认为是一个简单的线性转换断层系统的一部分。
A large strike‐slip earthquake occurred in the Caribbean Sea on January 28, 2020. We inverted teleseismicPwaveforms from the earthquake to construct a finite‐fault model by a new method of inversion that simultaneously resolves the spatiotemporal evolution of fault geometry and slip. The model showed almost‐unilateral rupture propagation westward from the epicenter along a 300 km section of the Oriente transform fault with two episodes of rupture at speeds exceeding the local shear‐wave velocity. Our modeling indicated that the 2020 Caribbean earthquake rupture encountered a bend in the fault system associated with a bathymetric feature near the source region. The geometric complexity of the fault system triggered multiple rupture episodes and a complex rupture evolution. Our analysis of the earthquake revealed complexity of rupture process and fault geometry previously unrecognized for an oceanic transform fault that was thought to be part of a simple linear transform fault system.