Quaternary:the time for Qaidam Basin fell into its final configuration
Yang Jin Huang Zhongfan Dai Fugui Yang Kesheng (Research Institute, BGP, CNPC, Zhuozhou 072751,China)
Qaidam Basin was developed on the double basements of both crystal and fold. Fault depression and unsymmetrical fault-depression were formed during Jurassic extension evolution. Fault depression and unsymmetrical fault-depression were also formed during Paleogene extension evolution. Syndeposition type of sedimentary basin was formed during Neogene-Quaternary compressive evolution. The Quaternary strong squeeze caused the formation of unified overthrust and thrust nappes in Qaidam Basin. Finally Quaternary anticlines and gas reservoirs were formed to their final configuration in the continental basin with multiple structural layers, which are called Tainan, Sebei 1 and Sebei 2 and characterized with negative anticline configuration on seismic section due to chimney effect resulted from velocity reducing in the gas-filling-reservoir. The discovery of this type of gas reservoirs indicates that the exploration for gas and oil reservoirs of similar structural style in other basins should not be ignored.
【CateGory Index】： P618.13