资源环境科技发展态势分析平台

We use a recent compilation of geodetic data of surface displacements in a fully Bayesian approach to derive a probabilistic estimate of interseismic coupling along the Main Himalayan Thrust (MHT). Our probabilistic estimate of interseismic coupling highlights four large, highly coupled patches separated by three potential barriers of low coupling. Locked patches overlap with estimated rupture areas of historical large earthquakes over the past centuries. The coincident spatial variability in coupling, seismicity, and prominent active topography suggests a structural segmentation of the MHT imposed by inherited tectonic structures from the India-Eurasia collision. This correlation implies that inherited tectonic structures may affect how stress builds up along the MHT, thereby influencing the location and size of large Himalayan earthquakes and the growth of the mountain range.

Plain Language Summary Large Himalayan earthquakes occur along the plate interface between the Indian and Eurasian plates: the Main Himalayan Thrust. Structural complexities of the downgoing Indian plate are thought to play a role in the segmentation of this large fault and hence its seismic potential. However, it is not clear how these tectonic structures affect the interseismic stress buildup between earthquakes. With geodetic data and a fully Bayesian approach, we estimate the pattern of interseismic coupling along the Main Himalayan Thrust, defined as a measure of kinematic locking along fault interfaces. We observe a heterogeneous distribution of interseismic coupling that coincides with the pattern of large earthquakes, topography, and subsurface ridges inherited from the India-Eurasia collision.