Abstract In this paper, we study the spatial distribution and temporal evolution of the postseismic deformation of the 2010–2011 Rigan earthquake sequence which occurred at the southern termination of the East Lut fault system, southeast Iran. One-year GPS measurements after the Rigan earthquake sequence reveals right-lateral postseismic displacement along the East Chahqanbar fault and left-lateral postseismic displacement along the South Chahqanbar fault. To investigate the deformation variations in time and space, InSAR time-series of COSMO-SkyMed images is applied using the Small Baseline Subset algorithm. The results confirm a clear cumulative postseismic signal increasing to 8 mm during the first five months following the first mainshock in the direction of the coseismic displacement. The cumulative postseismic displacements are well correlated with the cumulative number of the aftershocks and their associated moment release. Considering this correlation and the observation of a sharp discontinuity along the coseismic fault in the displacement map, it is concluded that the after-slip mechanism is responsible for the observed postseismic deformation in the study region. This study is the first observation of a short-term postseismic motion in eastern Iran through geodetic data in contrast with long-lasting postseismic displacements following the earthquakes that occurred around Lut block. Modeling of the postseismic displacement results in a distributed slip pattern with a maximum slip of 0.8 m on the fault plane responsible for the 2010 Rigan coseismic deformation. This indicates that the postseismic deformation on barriers remained unbroken during the mainshock.

中文翻译：

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使用大地测量数据研究伊朗西南部 2010-2011 年里根地震序列的震后变形

摘要 在本文中，我们研究了发生在伊朗东南部东卢特断层系统南端的 2010-2011 年里根地震序列的震后变形的空间分布和时间演化。里甘地震序列后一年的 GPS 测量显示沿东察坎巴尔断层的右侧震后位移和沿南察坎巴尔断层的左侧震后位移。为了研究时间和空间的变形变化，使用小基线子集算法应用 COSMO-SkyMed 图像的 InSAR 时间序列。结果证实了在同震位移方向上的第一次主震后的前五个月内，明显的累积震后信号增加到 8 毫米。累积震后位移与余震的累积次数及其相关的力矩释放密切相关。考虑到这种相关性以及在位移图中沿同震断层观察到的明显不连续性，可以得出结论，后滑动机制是研究区观察到的震后变形的原因。这项研究是首次通过大地测量数据观察到伊朗东部的短期震后运动，与 Lut 地块周围发生地震后的长期震后位移形成对比。对震后位移的建模导致在造成 2010 年 Rigan 同震变形的断层面上出现最大滑移为 0.8 m 的分布式滑移模式。