Abstract:
The Lianhuashan fault zone is an important NE-trending tectonic belt on the southeastern continental margin of China. It is not only an important boundary of secondary tectonic units but also controls the most important tin-copper polymetallic metallogenic belt in Guangdong Province. Previous studies show that the ductile deformation in Lianhuashan fault zone is closely related to the tin-copper polymetallic mineralization. However, there are still some disputes about the distribution of ductile deformation and its contribution to mineralization in Lianhuashan fault zone. In this study, by means of large-scale structural mapping and typical geological profiles of the Lianhuashan fault zone, in combination with the measurement of tensile lineation attitude and the observation of microstructure, the authors have reached the conclusion that the ductile deformation in the fault zone was formed by a series of in-situ shear zones striking nearly 60° in N-S direction, which are roughly parallel to each other. After ductile deformation, these shear zones were cut by brittle faults striking 30°. Ductile deformation controls the shape and scale of orebodies in Lianhuashan fault zone. In the late magmatic and hydrothermal activities, the space of preexisting ductile shear zone was utilized to precipitate and enrich metallogenic elements in the cracks of ductile deformation. The ore-prospecting work in Lianhuashan fault zone should be arranged around the ductile deformation area and should pay attention to the ore-hosting fractures near the ductile deformation.