Late Mesozoic Sedimentary Records Of Maoming Basin And Its Relationship With The Evolution Of Proto-south China Sea

The South China Sea is one of the biggest marginal sea of the western Pacific, t which located on the intersection of Eurasian, Pacific and Indian- Australian plates. Since the late Mesozoic, the subduction and extinction of Proto-South China Sea and the charactor of its northern continental margin are the hotspots and the leading edge of academia. As on the northwest of the South China Sea, Maoming basin preserved the keep from the volcanic-sedimentary records from early Cretaceous to Pliocene almost continuously, which means a ideal place for testing the charactor of continental margin.Based on the sedimentary analysis of the Maoming basin given priority to, the writer use the source rocks analysis and geochemical approaches, combined with stratigraphy and magma petrology data, to deduce the space-time distribution and the evolution of basin. Compared with the other basins on the northern continental of the South China Sea comprehensively, applied the theory of Tectonic Sedimentology to explore the tectonic environment of Maoming basin in late Paleozoic and its relationship with the evolution of Proto-South China.The volcanic rocks in Maoming basin recorded large-scale volcanic eruption three times during the late Cretaceous, whereas the later sedimentary records with typical epicontinental arc characteristics together indicate that at this time the Andean continental arc is in a peak period of activity. At the end of the late Cretaceous the basin occurred relatively strong tectonic uplift caused the lack of Palaeocene, it obviously marked the last stage of the marginal arc and ended the active charactor of the basin, and the Oligocene have tuned to passive continental margin environment. Sedimentary association system in the study area shows that the subduction of Proto-South China is likely to be deep into the northwestern margin of the modern South China Sea in late Mesozoic movement, and provide a preliminary basis to the extended study of the "Tethys-South China Sea".