Sedimentary reservoir characteristics and exploration significance of submarine fan under the dual control of provenance and geomorphology:Taking the Meishan Formation in Qiongdongnan Basin as an example
The submarine fan of the Miocene Meishan Formation in the Qiongdongnan Basin is an important target for natural gas exploration in the northern South China Sea.Its sedimentary mechanism and main reservoir controlling factors directly influence the natural gas exploration and production in this area.According to sea level change,seabed topography and geomorphology,syngenetic fault combination etc.,the submarine fan of Qiongdongnan Basin has been divided into three categories:shelf fan,slope fan and basin floor fan.Based on a large amount of measured data such as core and sidewall coring,this paper systematically analyzes the submarine fan reservoir revealed by drilling in this area.The study shows that the physical properties of the Meishan Formation submarine fan reservoir in Qiongdongnan Basin are not only affected by the buried depth,but also affected by the provenance and geomorphic units.Specifically,the basin floor fan reservoir from the western East Vietnam provenance and the northwestern Ningyuan River provenance are significantly better than the shelf fan and slope fan reservoir from the northern Lingshui River and Wanquan River provenance.The single submarine fan reservoir is controlled by such factors as provenance,sea level change,the type of fan body and internal composition as well as underflow modification.Among them,the type of submarine fan and its internal composition as well as underflow modification are main factors that affect and control the quality of turbidite reservoir.The gentle slope fault-terrace basin floor fan at the lowstand stage,basin floor fan in the open depression and canyon-cut basin floor fan are important exploration targets for their good-to-high quality reservoir.By contrast,the basin floor fan of steep slope root and gentle slope last-stage fault-terrace basin floor fan possess high exploration risks due to poor reservoir physical properties or undeveloped reservoir.Consequently,the research results of submarine fan reservoir based on provenance system and geomorphic units can be widely applied to the prediction of deep-water submarine fan reservoir.
Northern South China SeaMeishan FormationSubmarine fanProvenance systemHigh quality reservoir
万方数据
维普
