Qinzhou residual geosyncline” has been considered to be formed by folding inversion in Dongwu Revolution.

Based on the data of lithological association,petro-geochemistry and paleontology integrated with anal-ysis of geotectonic evolution and marine /continental change,this paper presents that the Late Permian Lucaogou forma-tion is lacustrine deposit modified by residual trough with aquifer medium of lake water formed by terrestrial facies.

Establishment of residual stratum framework and its subdivision in complex fault block reservoirs;

Types,features and studying method of continental relict basins;

Based on previous researches, evolution mechanism and distribution characteristics of relict basins are stated.

The structural characteristics such as vertically stratigraphical sequence hiatus,planar sedimentary system and facies incompleteness,delimitation of a basin by erosion or fault,and the structural feature of outcrop in peripheral and near arears could be taken as marks in recognizing relict basins.

Mesozoic remnant basin characteristics and hydrocarbon exploration direction on East China Sea shelf;

Petroleum potential and exploration direction of pre-Tertiary remnant basins in Offshore China;