A relic thickened crustal root beneath the Cenozoic rift zone of the NW Ordos margin, North China, revealed by receiver functions

We investigate the crustal structure and Moho topography beneath the northwest Ordos rift zone by employing receiver functions analysis at dense broadband seismic stations. The results delineate a depressed Moho zone (by ∼5 km) beneath the Cenozoic rifts, which is unconventional for classical continental rift zones. We interpret this depressed Moho zone as a relict of the thickened crustal root formed during the intracontinental orogeny in late Mesozoic. The Cenozoic rift has not yet reequilibrated the crustal-mantle boundary possibly due to the lack of decompressional melting during the lithospheric extension.