Segmentation of the Main Himalayan Thrust illuminated by Bayesian inference of interseismic coupling

Luca Dal Zilio (1, 2) , Romain Jolivet (3, 4) , Ylona van Dinther (5, 2)

1 CALTECH - California Institute of Technology
2 ETH Zürich - Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich]
3 LGENS - Laboratoire de géologie de l'ENS
4 IUF - Institut Universitaire de France
5 Utrecht University [Utrecht]

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.

Domaines: Planète et Univers [physics]; Sciences de la Terre; Géophysique [physics.geo-ph]

Luca Dal Zilio, Romain Jolivet, Ylona van Dinther. Segmentation of the Main Himalayan Thrust illuminated by Bayesian inference of interseismic coupling. Geophysical Research Letters, 2020, 47 (4), pp.e2019GL086424. ⟨10.1029/2019GL086424⟩. ⟨hal-02485458⟩