Analysis On Main Control Factors For Hydrocarbon Accumulation In Liaohe Tidal Zone

In Liaohe tidal zone, oil-gas reservoir conditions is more complex. The main source rocks include E2S3, E2S1, E2d3, and gather in two sag(Hainan sag and Gaizhoutan sag). Maturity of source rocks is better, the majority has reached the limit throttle Health and can provide a wealth of oil and gas region. Reservoir-seal combination in this area focuses on E2S and E2d, and come in many forms. At the same time, the region has multiple types of traps, oil and gas gather around the two sag.Analysis of the Liaohe Tidal Zone western, central and eastern areas of the three typical characteristics of hydrocarbon accumulation, Recognized: (1) In Bijialing of the tidal zone west, part of hydrocarbon source rocks have good hydrocarbon generation capacity, but the oil and gas mainly come from the neighboring deep depression of Hainan, and focus on the E2d3 E2S1+2 reservoir. Sand body developed well, and had the nature of good connectivity. As a result of dumping stratigraphy relief and dueing to development of faults, so the main hydrocarbon accumulation is characterized by lateral migration; (2) In Yuedong– Hainan of the central tidal zone, hydrocarbon come from two sag, and fracture develop well particularly, coverd with the whole region. The migration was vertical through the fracture. As part of long-term active fault, the main features was that the controlled storage conditions impact accumulation in this area. (3) In Sun Island–Sunflower Island of tidal zone east, the oil and gas mainly come from the neighboring deep depression of gaizhoutan, and focus on the E2d reservoir. Stratigraphy was so steep that links between source rocks and reservoir was bad, and then they communicated only through the fracture. Thus oil and gas vertical migration is one of the main characteristics of hydrocarbon accumulation.Through analysis of a typical region, adverse conditions of hydrocarbon accumulation was sumed up in beach area: The main disadvantage of the western region provided that the associated conditions and trap; reservoir,preservation conditions and trap become the main adverse conditions in the central region; The eastern region was reservoir and conducting conditions. conditions of accumulation collated into the Liaohe tidal zone was divided into five major categories, including source rocks, reservoir, trap, storage and matching. And then they were quantified by the geological risk probability method. Using multiple linear regression model, it get affecting relationship equation between hydrocarbon accumulation and accumulation condition through fitting in the SPSS software. And the greatest impact conditions was calculated. At last it determined the controlling factors of oil and gas accumulation through the integrated study of reservoir conditions and comparison analysis between accumulation adverse factors and the results. The controlling factors of oil and gas accumulation was matching conditions (reservoir cap configuration) in the western region; was preserve (the degree of fracture damage) in central region; was reservoir (the degree to communicate with the of source rock) in eastern region.