Deep crustal contact between the Pamir and Tarim Basin deduced from
receiver functions
Abstract
The deep crustal deformation in the east Pamir in response to Cenozoic
collision with the Tien Shan and Tarim Basin is so far poorly
constrained. We present new insights into the crustal structure of the
east Pamir and the surrounding regions using P receiver functions from
40 temporary and permanent seismic stations. The crustal thickness
reaches a maximum of 88 km beneath the central and southern east Pamir
and decreases sharply to 50-60 km along the southern Tien Shan and to
41-50 km below Tarim Basin. The most prominent crustal structures
involve a double Moho and two Moho offsets, which suggest that the
crustal deformation in the east Pamir is controlled by multiple
mechanisms, including delamination of Asian lower crust below the
central east Pamir, pure shear shortening along the northeastern margin
between the Pamir and Tarim/Tien Shan and eastward underthrusting of
Pamir lower crust beneath the southern east Pamir.