Abstract:
Hengyang Basin is located at the junction between Jiangxi- Hunan-Guangxi-Guangdong fold belt of South China fold system and Jiangnan platform uplift, with the development of multi-stages and multi-types metallic and non-metallic deposits. The systematic summarization of regional metallogenic regularities is deficient in current research, which hinders the establishment of metallogenic theory and ore prospecting. The authors in this paper summarized and analyzed the characteristics of magmatism and metallogenesis, temporal and spatial distribution of Hengyang Basin. The results show that multi-stage magmatism and mineralization were developed since Paleozoic, mainly in Indosinian and Yanshanian Period. Most of the main metal deposits in the basin are closely related to magmatism, and the mineralization types developed from high temperature to low temperature exist. The spatial distribution of rock mass and deposits in the basin is closely related with the deep-seated fractures, and various types of vertical zoning are developed in each deposit. Three different types of mineralized assemblage zones are developed in the basin from northwest to southeast, with mineralization temperature rising gradually. The
Hengyang type basin and range structural belt are mainly controlled by the effect of lower mantle plume activities under the tectonic setting of multi-stage lithospheric extension in South China. The diagenesis and metallogenic activities are triggered by the superposition of multiple process, including partial melting and fractional crystallization in different locations of the lithosphere, upwelling of deep fertile ore fluid and the extraction of metals from surrounding rocks. The research results could provide some references for the study of metallogenic regularity and further prospecting in Meso-Cenozoic basins in South China.