Our purpose is to infer the mechanical state of the lithosphere beneath the Himalayas and to evaluate the role of the lithospheric mantle in the support of the loads. Earthquake locations, focal mechanisms, and seismic imaging results from the HIMNT experiment, combined with previous constraints on the geometry and deformation of the Himalayan collision, are used to set up the finite element models of lithospheric loading.
Using a finite element model, we establish a link between the recorded upper mantle seismicity beneath the Himalayan collision zone and flexural bending of the Indian lithosphere. Earthquake locations from several experiments place seismic events in the upper mantle. The question of whether the near-Moho earthquakes are in the crust or in the upper mantle has been controversial, and has raised another question about the role of the mantle in the support of mountain loads and its ability to deform by brittle processes. Recorded seismicity at the Himalayan collision zone suggests that earthquakes occur mainly at upper crustal depths and near the crust–mantle boundary. The Indian Plate underthrusts the Himalayan mountains and the southern Tibetan Plateau. The Himalayas and the Tibetan Plateau are the result of the continental collision between India and Eurasia.