摘要
The Heyuan Fault, is one of the main NE-trending faults in the southernmost South China Block and is close to the northernmost South China Sea to the south. The fault features multi-stage deformation and controlled the formation of late Cretaceous to Cenozoic basins. Based on detailed field investigations and comprehensive geochronological research, including zircon U-Pb, Rb-Sr isochron, zircon U-Th-He dating, two episodic tectono-thermal events are recognized. The first occurred during ~79 Ma to 66 Ma, which is characterized by large-scale quartz-fluid emplacement. The other occurred at ~34 Ma, which features the eruption of a set of basalts. The two events show a changing on material source from siliceous hydrotherm to basalt magma, supporting obvious lithospheric thinning of the southernmost South China Block, which shed light on the geological evolution and the interaction mechanisms between the SCB and the northern South China Sea since the Late Cretaceous.
基金
jointly supported by projects, including the Study on the Lithospheric Thermal Structure, the Formation Mechanism of Geothermal Systems, and the Assessment of Geothermal Resources of the Guangdong-Hong Kong-Macao Greater Bay Area (Grant No.U20A2096)
The Huizhou Multi-factors Urban Geological Survey Project (Grant No.DD20190287)
the Update and Sharing of China Geological Maps of Land and Sea areas (Grant No.DD20190370)。