The early Precambrian crustal evolution of China

Abstract

The Archaean continental crust in China originated from dispersed nuclei under the influence of whirl tectonics 2.5 Ga ago. From the beginning of the early Proterozoic, the crustal evolution process was controlled by the plate tectonics. A tectonic regime of coexisting mobile belts of different characteristics and rigid blocks emerged. The diversity of tectonic setting and structures marked the beginning of a new epoch of crustal evolution. The north China protoplatform, the Tarim protoplatform and the Yangtze protoplatform are considered to have separated from each other by least at the end of Archaean, based on the early Proterozoic accretion zones developed between them. Cathaysia gradually moved closer to the Yangtze protoplatform in the early Proterozoic. The nearly north-south primary structural trend of the early Proterozoic formations in the northern margin of the modern north China platform indicates that the north China protoplatform had been connected with the Siberian craton during and before early Proterozoic times.