NEW BRIEF REMARKS ON HYDROCARBON PROSPECTING OF MARINE STRATA IN THE MIDDLE AND UPPER YANGTZE REGION

With the development of research and exploration,the dominance of marine oil and gas exploration is overhanging in Middle and Upper Yangtze region.Based on establishment of regional sequence stratigraphic framework,it is pointed out that the regional main source rocks are Z₂ds(SS1-TST),lower-C₁(SS3-TST),O₃w and lower S1(SS7-LST,TST),P₂q(SS12-TST),P3(SS13-TST),expect that Wufeng Formation(O₃w) formed in SS7-LST,others formed in the transgressive system tract of the supersequence.While the high-quality regional reservoirs would be consistent with the highstand of the supersequence,they are Z₂d(SS2-HST),-C₂,-C₃(SS4-HST),C₂(SS11-HST),P₂m(SS12-HST),P₃ch-T₁,T₂(SS13-TST,HST).The distribution of the regional cap rocks are the same as the regional main source rocks,however,their types are more abundant,and they formed at the same time of second-order sea-level rising quickly.Finally,it is suggested that reef flat limestone-dolomitized limestone/dolomite-palaeokart are the most favorable reservoirs,paleohigh+late structural-lithologic strata traps are the most favorable location,and northeastern Sichuan-western Hubei area(two platform margins and one platform) and southeastern Sichuan-Middle Guizhou-western Hubei area(one platform margin and one platform) are the priority area,southeastern Sichuan-northern Guizhou and western Hubei-eastern Chongqing are the frontier where exploration breakthrough would be expected in the near future.