DEEP TECTONIC INFORMATION OF MAGMATIC ROCKS ALONG THE YANGTZE RIVER IN ANHUI

Mesozoic magmatic rocks are widespread along the Yangtze River in Anhui. According to the composition of the magmatic rocks, rock associations, deep crustal structure, mineralization and Nd, Sr and Pb isotopic compositions and ratios, three magmatic belts may be distinguished. In the inner belt, there are mantle derived basic to intermediate acid intrusive rocks resulting from the evolution of alkaline basaltic magmas, in which there occur skarn Cu, Fe, S and Au deposits. In the north outer belt, intermediate acid intrusive rocks predominate, belonging to the product of the anatexis of the lower crust. The south outer belt is dominated by S type granite, showing the features of the anatexis of the upper crust. The south and north belts are both marked by calc alkaline series, in which porphyry Cu deposits occur.