Abstract:
Due to the fact that apatite is a common accessory mineral in magmatic rocks, its geochemical composition is often used to indicate the petrogenesis of granites and provide constraints on their magmatic properties. Mesozoic A-type granites are widely distributed in the eastern Jiangnan Orogen. At present, the origin of these A-type granites is still controversial, and their mineralization potential is not clear. Therefore, this study investigates the geochemical composition of apatite in the Yaocun granite, constrains the magmatic properties, and evaluates its metallogenic potential. The results show that the apatite in Yaocun granite generally exhibits oscillatory zoning or homogeneous texture, and has high F, REE, Y, and Th, and low Cl contents, indicating its magmatic origins. In addition, the REE, Y, and Th contents of a single apatite grain show continuous changes from the core to the rim, and the REE pattern displays obvious negative Eu anomalies, which can be attributed to fractional crystallization. Quantitative calculations show that Yaocun granitic magma is characterized by high F, low H
2O-Cl, and low oxygen fugacity. Considering the relation between magmatic properties and the behavior of ore-forming elements, our study suggests that Yaocun granite has rare metal mineralization potential.