Of all the oil and gas shows in the marine strata in Central Yangtze Region

bitumen is most common

then oil shows

and the gas shows are the last.Since hydrocarbon evo-lution degrees are different

bitumen is mostly in Lower Paleozoic

gas shows mainly in the Silurian and Devonian

and oil slows in the Permian and Triassic.This indicates that gas exploring should aim at the Paleozoic and oil at Mesozoic.The oil and gas shows are concentrated in the two limbs of Huangling anticline

the north margin of South Jiangnan Uplift and the two limbs of Chenhu-Tuditang syncline.It is obvious that the loss of oil and gas are bound up with strong uplift and denudation.Tensile and tensile-shear faults are the principal factor in controlling oil and gas shows

and the migration path and accu-mulation space as well as the chief factor of hydrocarbon lossing.Most of the oil and gas showings are in fracture

fracture-miarolitic cavity and fracture cave.The study of oil-gas shows indicates that

Lixian Sag is one of the best areas in hydrocarbon potential in the Central Yangtze Region.The fault draps covering the footwall of the faults are favourable storages.The limbs of Chenhu-Tuditang syncline are the localities for the migration

accumulation and escape of hydrocarbon

and the place of the unity of oppo-sites is important for seeking oil and gas.