Late Paleoproterozoic breakup events of North China: Evidence from LA-ICP-MS zircon U-Pb ages of basaltic andesite from the Daqingshan area in Inner Mongolia

During the 1∶50000 regional geological survey in Daqingshan area of Inner Mongolia, the authors used LA-ICP-MS zircon U-Th-Pb isotopic dating method and obtained weighted average zircon U-Pb age of 1863±10Ma from the Jurassic volcanic rock. The contact relation is considered to be unconformably covered by Upper Permian Naobaogou Formation, as shown by field survey. According to the major, trace and rare earth elements analytical results of the rock, the basaltic andesite was formed in an intracontinental rift. This was a breakup event between multi -stage rifting in the Late Paleoproterozoic to Neoproterozoic in North China. It is of great significance for studying multi-stage rifting and provides an important basis for the North China Craton (NCC) evolution as a stable platform or para-platform.