CHARACTERISTICS OF PROTEROZOIC BASEMENTS ON THE GEOCHEMICAL STEEP ZONES IN THE CONTINENT OF CHINA AND THEIR IMPLICATIONS FOR SETTING OF SUPERLARGE DEPOSITS

Based on the Pb isotopic mapping of the continent of China and the geo chemical data of Proterozoic basements, the steep zones of geochemical blocks of Cathaysia, Yangtze, North China, Central Mongolia, China-Ko rea and Jiamusi are established. There are tight relationships between geochemical steep zones and setting of the superlarge deposits along with main mineralization zones. There are Proterozoic basements belong ing to different blocks on both sides of geochemical steep zones in wh ich volcanism and SEDEX were comprehensively developed and associated with reconstruction ore emplacement of dynamic metamorphism and magmat ism from Jinning period to Mesozic-Cenozoic.