The Mechanism and Characteristics of Oil and Gas Migration and Accumulation in Shallow and Deep Water of ZhujiangkouBasin, Northeastern South China Sea
The geological conditions for oil and gas accumulation are of significant difference in shallow and deep waters in the ZhujiangkouBasin. The difference is resulted mainly from the different mechanism of migration and accumulation of oil and gas and their distribution pattern. The mechanism of hydrocarbon migration and accumulation in the half-grabens has been verified by exploration but no breakthrough has been achieved so far. The hydrocarbon of mixed sources has been verified in the Oligocene deltaic sandstone and deep-water fan systems, characterized by the coexistence of gas hydrates in seafloor and shallow gas and conventional oil and gas in the deep.