Located at the northwest continental slope of the South China Sea, the Qiongdongnan Basin bears valley-shaped bathymetry deepening toward east. It is separated from the Yinggehai Basin through NW-trending Indo-China-R...Located at the northwest continental slope of the South China Sea, the Qiongdongnan Basin bears valley-shaped bathymetry deepening toward east. It is separated from the Yinggehai Basin through NW-trending Indo-China-Red River shear zone, and connected with NW subsea basin through the Xisha Trough. Along with the rapid progress of the deepwater exploration, large amounts of high resolution geophysical and geological data were accumulated. Scientific researches about deepwater basins kept revealing brand new tectonic and sedimentary discoveries. In order to summarize the structural features and main controlling factors of the deepwater Qiongdongnan Basin, a series of researches on basin architecture, fault activities, tectonic deformation and evolution were carried out. In reference to analogue modeling experiments, a tectonic situation and a basin formation mechanism were discussed. The researches indicate that:the northern boundary of the Qiongdongnan Basin is strongly controlled by No. 2 fault. The overlapping control of two stress fields from the east and the west made the central depression zone extremely thinned. Combined with the changed stress field, the segmentation of a preexisting weakness zone made the sags in the east experiencing different rifting histories from the west ones. The NE-trending west segment of the Qiongdongnan Basin experienced strong rifting during Eocene, while the roughly EW-trending sags in the east segment show strong rifting during late Eocene and early Oligocene. Local structures such as NW-trending basal fault and inherited uplifts controlled the lateral segmentation. So first order factors such as regional stress field and preexisting weakness zone controlled the basin zonation, while the second order factors determined the segmentation from east to west.展开更多
From a point of magmatic view,the rupturing Gondwana Supercontinent is registered on the South American shelf in continental flood basalts,mafic dyke swarms,basins rift and,to a lesser extent,by intrusions alkaline.Am...From a point of magmatic view,the rupturing Gondwana Supercontinent is registered on the South American shelf in continental flood basalts,mafic dyke swarms,basins rift and,to a lesser extent,by intrusions alkaline.Among those展开更多
The Yinggehai basin lies in the northwestern shelf of the South China Sea. The maximum depth of the Cenozoic sediments is 17 km. Present gas exploration was mainly in the Neogene strata. But it is estimated that the P...The Yinggehai basin lies in the northwestern shelf of the South China Sea. The maximum depth of the Cenozoic sediments is 17 km. Present gas exploration was mainly in the Neogene strata. But it is estimated that the Paleocene sediments (~8 km in thickness) has productive potential. So research on the Paleogene rifting structure will greatly enlarge the exploration area. 3D scaled sandbox is the analogue model for the Yinggehai basin. Comparing modeling with the basin by the positions and movement of depocenters, the geometric similarity, we aim to summarize the dynamic situation of Yinggehai basin during the rifting stage and to cast an objective prediction on the structures in the areas without data.展开更多
基金The Major National Science and Technology Programs of China under contract No.2011ZX05025-003-005the Joint Program of the National Science Foundation and Guangdong Province under contract No.U1301233
文摘Located at the northwest continental slope of the South China Sea, the Qiongdongnan Basin bears valley-shaped bathymetry deepening toward east. It is separated from the Yinggehai Basin through NW-trending Indo-China-Red River shear zone, and connected with NW subsea basin through the Xisha Trough. Along with the rapid progress of the deepwater exploration, large amounts of high resolution geophysical and geological data were accumulated. Scientific researches about deepwater basins kept revealing brand new tectonic and sedimentary discoveries. In order to summarize the structural features and main controlling factors of the deepwater Qiongdongnan Basin, a series of researches on basin architecture, fault activities, tectonic deformation and evolution were carried out. In reference to analogue modeling experiments, a tectonic situation and a basin formation mechanism were discussed. The researches indicate that:the northern boundary of the Qiongdongnan Basin is strongly controlled by No. 2 fault. The overlapping control of two stress fields from the east and the west made the central depression zone extremely thinned. Combined with the changed stress field, the segmentation of a preexisting weakness zone made the sags in the east experiencing different rifting histories from the west ones. The NE-trending west segment of the Qiongdongnan Basin experienced strong rifting during Eocene, while the roughly EW-trending sags in the east segment show strong rifting during late Eocene and early Oligocene. Local structures such as NW-trending basal fault and inherited uplifts controlled the lateral segmentation. So first order factors such as regional stress field and preexisting weakness zone controlled the basin zonation, while the second order factors determined the segmentation from east to west.
文摘From a point of magmatic view,the rupturing Gondwana Supercontinent is registered on the South American shelf in continental flood basalts,mafic dyke swarms,basins rift and,to a lesser extent,by intrusions alkaline.Among those
基金the MarginalSeaOpenL aboratory!(No.KZ951-B1-406-02)Mineral Resources Quantitive Prediction Explorative Evaluation Open L
文摘The Yinggehai basin lies in the northwestern shelf of the South China Sea. The maximum depth of the Cenozoic sediments is 17 km. Present gas exploration was mainly in the Neogene strata. But it is estimated that the Paleocene sediments (~8 km in thickness) has productive potential. So research on the Paleogene rifting structure will greatly enlarge the exploration area. 3D scaled sandbox is the analogue model for the Yinggehai basin. Comparing modeling with the basin by the positions and movement of depocenters, the geometric similarity, we aim to summarize the dynamic situation of Yinggehai basin during the rifting stage and to cast an objective prediction on the structures in the areas without data.