The Garden.empress ~ An Yue Area Must Be Mode And Control Factors Of Hydrocarbon Accumulation In The Center Of Analysis

Renshou-Anyue district is located in the north of vying structure, the gentle slope belt in the southwest of Sichuan Basin, the Xujiahe Formation has more multifarious oil spirit a manifestation in the process of drilling, account for Xujiahe Formation in this region has huge potential for exploration and development. The paper used Petroleum system as a foundation, adopted a research method which combined with geology, sedimentation and geochemistry, combining previous research achievements, systematically studied the basic geological conditions and the causes of natural gas, ascertain the periods of gas reservoir formation, set up gas accumulation mode, and summarized principle factors controlling gas reservoir formation.Based on a lot of analysis and assay material research shows that hydrocarbon source rock of Xujiahe formation was high organic matter abundance, achieved a good hydrocarbon source rocks level; Kerogen type is mainly Ⅱ2～Ⅲ kerogen; The measured vitrinite reflectance between0.85%and1.24%,which be in mature period. The ability of generation oil or gas is stronge, the Hydrocarbon-generating intensity is15～55×108m3/km2.The paper used total hydrocarbon geochemical methods including natural gas composition and carbon isotope, condensate oil carbon isotopic composition, light hydrocarbon and gas chromatography, Confirmed that oil and gas from Xujiahe group mainly comes from autogenic coal source rock, and bind is main, is typical of self-generation and self-storage.The hydrocarbons of Xujiahe formation mainly migrated in gas phase and vertical migration, middle Triassic erosion surface、fault and crack provide good migration channel for oil and gas, the ancient uplift and reservoir with relatively large porosity and permeability are advantage places for gas concentration, the main gas reservoir types are Anticline gas reservoir related with ancient uplift and lithologic gas reservoir.The hydrocarbon injection of Xujiahe formation mainly occurred in the late Jurassic to tertiary, its mainly petroleum accumulation period divided into three stages:Late Jurassic to the early Cretaceous, namely mid-late Yanshan Period, was early accumulation phase; late Yanshan to early Himalaya was the foremost stage of gas communication; mid-late Himalaya was the stage of gas adjustment redistribution.The master control of natural gas concentration of Xujiahe formation were ancient uplift、fault and crack、favorable reservoirs and hydrocarbon source rocks. Thereinto, ancient uplift is favorable directional zone of hydrocarbon migration and the most favorable hydrocarbon concentration site; fault and crack is not only providing good migration channel but also improving reservoir permeable capacity, creates conditions for oil and gas accumulation; reservoir with relatively large porosity and permeability is the foundation of lithologic reservoir, underwater distributary channel deposit controlled the distribution of sand bodies of high quality, which affect the oil and gas distribution and hydrocarbon accumulation; Middle Triassic erosion surface creates favorable conditions for hydrocarbon enrichment of Xu-2mengbers.