Devonian reef development and strata-bound ore deposits in South China

This study focuses on the close association between Devonian reefs and the strata-bound ore deposits in South China. For the first time, the development of Devonian reefs was subdivided into three stages, respectively as the initial, succeeding and peak stages, and its evolution model is proposed. In Dachang, Nandan county, Guangxi Zhuang Autonomous Region(Guangxi for short), a large-scale strata-bound ore deposit formed in a Devonian reef, which was affected by marine volcanic activities and Mesozoic magmatic intrusions. The reef-building reached its peak stage at the Givetian, indicating a large-scale build-up of reef and inter-reef depression. In central-eastern Hunan Province, the strata-bound ore deposits belong to low-temperature ore-types without later magmatic intrusions or volcanic activities. In Hunan Province as well as many other localities in South China, the Givetian reefs played important roles in mobilizing ore-forming materials from the surrounding pre-Devonian rocks, providing spaces and passages for transporting hydrothermal fluid, and progressing mineralization and accumulation of ore-forming materials.