Integration of geology, geophysics and geochemistry: A key to understanding the North China Craton

Archaean-Proterozoic crust, atop a thick (180 km), cold (40 mW/m(2)), melt-depleted mantle keel, characterised the North China Craton (NCC) at the end of the Precambrian. Differing ages for Pre-Cambrian crust and underlying mantle reveal decoupling brought about by repeated orogenic events over the history of the NCC. The most recent thermo-tectonic episode in the Mesozoic-Cenozoic virtually replaced/transformed all of the Precambrian lithosphere. Whether this was caused by "top-down" rapid delamination (<5 Ma) or "bottom-up" more protracted thermal/chemical erosion (ca. 100 Ma) depends on the interpretation of Jurassic to Cretaceous geological events. The eastern part of the craton east of the North-South Gravity Lineament [lithospheric boundary] has experienced the most re-activation. In the Palaeozoic-Mesozoic this region was intruded by kimberlitic magmas and cross-cut by the Tan-Lu fault zone and in the Mesozoic-Cenozoic, the eastern craton was the site of major mafic igneous activity. By the end of the Cenozoic the eastern craton was characterised by thermal highs [>64 mW/m(2)], thin continental lithosphere (<50 km) and thin crust (<32 km) adjacent to the infra-cratonic Bohai Sea. (C) 2006 Elsevier B.V All rights reserved.