The A-type granites, which are located in middle-lower reaches area of the Yangtze River, have a close relationship with uranium（gold）deposit. Some issues, particularly origin of the A-type granites, are still under debated. The related research to these A-type granites can enhance the genetic relationship with IOCG deposit, and provide the beneficial information regarding to the prospect direction. In this contribution of study, we systematically document the detailed investigation of three typical A-type granites, consisting of Chengshan, Hejiaao and Meilin intrusions. Combing with the previous results, comprehensive regional geological survey and geochemical analysis have been carried out to reveal the deeper insight with respect to the origin and forming processes of the A-type granites. We argue that the formation age of Chengshan, Hejiaao and Meilin intrusions is 127 Ma, which represents the latest magmatic event in the Lu-Zong Basin and forming in the lithosphere extension-thinning tectonic setting. These granites belong to A-type granites, which is caused by the comagmatic evolution. The original source is dominantly composed of epimetamorphic rock from likely Dongling Group, mixed with some mantle material, and fractional crystallization dominates the forming process, predominating by plagioclase and potassic feldspar.
Du Xin Wu Ming'an Zhou Taofa Zhang Shu Zhang Zanzan Wang Jing. Discussion on the genesis of A-type granites in southern Lu-Zong Basin, Anhui Province, China[J]. Chinese Journal of Geology, 2018, 53(2): 678-696.