Magnetotelluric Evidences of an On-going Destruction Process of North China Craton

摘要

North China Craton (NCC), which is one of the oldest Archean cratonic blocks in the world, isrnconsidered to be formed from the Archeozoic to Proterozoic. The major tectonic blocks of NCC comprise thernEast Block, the West Block and the Trans North China Orogen between them [1]. The study of deep structurernin the region is of great significance to reveal the evolution and destruction of ancient cratonic blocks. Manyrna seismic studies, utilizing seismic reflective, refraction, tomography and receiver function methods, arernconducted to reveal the velocity structure of NCC in the past decade [2-4]. According to seismologyrninvestigations, the present lithosphere of the east NCC is only ~80–100km thick, while the west part isrnbelieved to have preserved a seismically fast and thick lithospheric root of ~200 km [5]. It is widely acceptedrnthat the contrast between the two parts is related with the late Mesozoic destruction/delamination process ofrnthe North China Craton [6].