The Lithospheric Textural and Structural Features as well as Oil and Gas Evaluation in Lower Yangtze Area and Its Adjacent Region,China

摘要

The work presented in this paper is based on the results from deep geology investigation project( 85-06-203,1991 -1995) sponsored by Chinese ministry of Geology and Mineral Resources (MGMR).From the research and investigation, five significant discoveries were made. They are 1 .the discovery of Dabie-Zhoushan lithospheric fault and Binhai-Tonglu lithospheric cryptofault.2.the discovery of the effection of expanding diapirism in deep geology.3 the discovery of existence of at least three horizontal fracture zones in lithosphere.4 The discovery of low resistivity layers under metamorphie rocks (nappe), which might be some umnetamorphic sediments or relics of horizontal fracture zones after uplifting, they both indicated new oil and gas exploration domains and 5.The finding of marine strata or unmetamorphic deposit covered by volcanic rocks in eastern Zhijiang Province, it is also a new domain for hydrocarbon survey. In working area, the structures ol" lithosphere were studied and they could be classified into seven layers and eight blocks. Three rules which controlled uplift and subsidence blocks movement were suggested, and to the movement mechanism, a continent dynamic pattern with four comprehensive factors was established. The interpretation on three sets of fault systems for the first time make contribution to understand structures in the area. In this paper, the evolution of lithosphere was divided into five phases. The hydrocarbon resources were evaluated, and the next steps in oil and gas exploration are proposed in eight aspects.