No mafic layer in 80 km thick Tibetan crust

Abstract

Crustal doubling in Tibet and the Himalayas by underthrusting of the Indian plate is thought to require the presence of a mafic layer above the Moho. Here, the authors present seismic data which shows that the middle Lhasa Terrane has very low velocity (V p < 6.7 km/s) throughout the 80 km thick crust, which they suggest is predominantly felsic in composition.