Hydrocarbon Accumulation Regularity Of Pu Oil Layers In Tai9Block Of Songliao Basin

The paper, based on the interpretation of seismic data, studies the fault features andformation evolution history of the development of Putaohua reservoir in T9blocks. Throughthe fracture system partition and conducting fault set, the paper concludes that the faultsconnected with source rocks is through type oil source faults which shape in fault depressionperiod and act in depression period and phase inversion.According to the3d seismic data and drilling data, sand body distribution characteristicsand Sedimentary microfacies features have been concluded. Delta front subfaciesdepositional systems is taken as the principal thing on PU oil layers. distributary channelandriver sand sheet control are generated except estuary dam，natural barrier and flowing sand.The characteristic is typical river control.On the basis of the above research of fault and sand body, this thesis defines thecharacteristics of oil distribution and reservoir types through the anatomy of the oil and gasstatistics and typical reservoir. There are2types of oil and gas reservoir. One is fracturedreservoir including nose-shaped high traps and fault-lithology reservoirs and another is faultsealing reservoirs cooperating with fault and sand body.Through the fault and sand body space configuration relationship, this research analyzesthe process of Putaohua oil reservoir accumulation. Its controlling effects on oil-gasaccumulation are mainly shown in the following three aspects： the distribution oftransporting fault controlling the distribution range of oil-gas accumulation； trapdevelopment areas are the favorable for oil-gas accumulation and distribution； only the trapswhich communicated by transporting fault are the effective traps of oil-gas accumulation.According to the configuration relationships of the three elements of hydrocarbonaccumulation and process of hydrocarbon accumulation，this paper establishes the models ofhydrocarbon accumulation. Oil and gas accumulation models are that hydrocarbon fromunderlying K2qn1source rocks migrate along faults connected with source rocks, then itmigrates laterally into strata of Putaohua Reservoir with the ratio between sandstone andstratum being more than20%, due to blocking of cap rock in K2n. Finally oil and gasaccumulates in fault sealing traps, nose-shaped high traps and fault-lithology traps on partialpositive construction near faults connected with source rocks and forms oil and gasreservoirs.Eventually，according to the oil and gas accumulation controlling effects and models, the paper traps of oil-gas accumulation.