| Based on gravity anomalies, magnetic signatures, seismic dara, drilled wells, and geotectonic property and Cenozoic major tectonic deformation, three basement areas of the Cenozoic basin, i.e. the northern, the western and the southern ones, can be divided in South China Sea. The northern basement is characterized by Paleozoic metamorphic rock and Mesozoic residual faulted depression and it is be further divided into 3 subareas, which include the Beibu Gulf basement subarea, the Pearl River Mouth Paleozoic basement subarea and the Xisha Islands Paleozoic basement subarea. The western one is characterized by strike-slips and it includes 3 sub-zones, i.e. the Yinggehai Paleozoic basement subarea, the Zhongjiannan and the Wanan Mesozoic basement subareas. The southern one is more complex and it is divided to 2 sub-areas,i.e. the Zengmu early Cenozoic folded basement subarea and the Nansha Paleozoic-Mesozoic complex basement subarea. These 8 sub-areas are separated each other from the subduction-collision suture belt, the ophiolite suite belt, the deep-sea radiolarite belt, the mid-ocean ridge basalt belt and the deep great strike-slip fracturing belt. These belts show different evolution histories and dominate several types of geological characteristics of Cenozoic sub-basins in South China Sea. |
