PROTEROZOIC INTRACONTINENTAL RIFTING OF THE QINLING OROGENIC BELT: EVIDENCE FROM THE GEOCHEMISTRY OF SEDIMENTARY ROCKS

Ⅰ. INTRODUCTIONThe Proterozoic tectonic nature of the Qinling Orogenic Belt has fundamental importance in understanding the evolutionary history of the Qinling Belt and the North China and Yangtze (South China) cratons, where the Qinling Group plays a crucial role. Although there is a consensus that this group was mostly of the early Proterozoic age, much controversy still remains on its tectonic environment of formation.