Continental dynamics in a multi-convergent regime: a receiver function study from the North-South-Trending Tectonic Zone of China

Abstract

The North–South-Trending Tectonic Zone (NSTZ) marking the transition between West China and the North China Craton is an earthquake-prone region. The NSTZ is located along the junction between the Indian Plate–Tibetan Plateau collision and E–W extrusion, as well as the westward subduction of the Pacific Plate, thus constituting an important region for studies related to continental dynamics. Here, we investigate the structure of the crust and upper mantle along this zone by employing the H-k stacking of receiver function and the depth domain receiver function. Our results identify notable variation in crustal thickness, an elevation of the upper mantle discontinuities, and convective removal of the mafic lower crust through either delamination or Pacific Plate subduction beneath the region, generating a cold domain in the mantle transition zone. The converging tectonic stresses contribute to making the NSTZ an earthquake-prone zone.