Meso-Cenozoic Structural Deformation and Marine Gas Distribution of Upper-Yangtze Block in Southern China

On the basis of studying surface deformational characteristics,seismic section and basement properties,we discuss on spatiotemporal differences of structural deformation of marine carbonate layer series in different parties of upper-Yangtze block since Indo-China movement.The results show that multi-period superimposed movements control the processes of late natural gas accumulation.The buried faults and dragged anticline located in the front of fold-thrust belt is favorable relatively for marine hydrocarbon accumulation in western Sichuan;the continuation and local adjustment of paleoanticline of central Sichuan zone formed secondary gas reservoirs;a lot of faults and related folds grow in middle structural layer of eastern Sichuan zone,its hidden folds provides traps conditions to large gas reservoirs;excerpts for Sangzhi-Shimen synclinorium,it is very difficult to explore marine hydrocarbon in western Hunan.