近日，武汉大学许才军团队报道了2025年缅甸实皆7.8级走滑地震未造成地表变形。2026年9月10日出版的《中国科学：地球科学》杂志发表了这项成果。

2025年实皆MW_7.8地震为研究成熟走滑断层上的浅层应变分配提供了契机。利用Sentinel-1、ALOS-2和Sentinel-2观测，研究组获得了同震形变场，绘制了缺失地表形变（ASD）的沿走向分布，并联合反演了断层几何与滑动。优选模型显示，倾角从北部约73°东倾转变为南部约84°西倾，且沿大部分破裂几乎没有明显浅层滑动亏损（SSD）。

ASD平均宽度约1.8 km，并在滑动过渡带、破裂端部及受蠕滑影响段附近变宽，表明存在局域化离断层形变，而非显著SSD。此外，破裂成核和主滑动凹凸体与残余应变高值区重合，表明构造继承促成了现今的破裂分段。这些结果界定了一种成熟断层浅层应变分配模式：高效到达地表的滑动与有限宽度的离断层损伤带共存。

附：英文原文

Title: Absent surface deformation from the 2025 MW 7.8 strike-slip Sagaing (Myanmar) earthquake

Author: anonymous

Issue&Volume: 2026-09-10

Abstract: The 2025 MW 7.8 Sagaing earthquake provides an opportunity to investigate shallow strain partitioning on a mature strike-slip fault. Using Sentinel-1, ALOS-2, and Sentinel-2 observations, we derive the coseismic deformation field, map the along-strike distribution of absent surface deformation (ASD), and jointly invert for fault geometry and slip. The preferred model shows a dip transition from ~73° east-dipping in the north to ~84° west-dipping in the south and little to no pronounced shallow slip deficit (SSD) along most of the rupture. ASD has an average width of ~1.8km and broadens near slip-transition zones, rupture ends, and creep-affected sections, indicating localized off-fault deformation rather than substantial SSD. In addition, rupture nucleation and the principal slip asperity coincide with a residual-strain high, suggesting that structural inheritance contributed to the present rupture segmentation. These results define a mature-fault mode of shallow strain partitioning in which efficient surface-reaching slip coexists with a finite-width off-fault damage zone.

DOI: 10.1007/s11430-025-2019-1

Source: https://www.sciengine.com/SCES/doi/10.1007/s11430-025-2019-1