The Characteristics Of Depositional Reservoirs And Their Effects On Hydrocarbon Accumulation In The Upper Part Of The Fourth Member Of Shahejie Formation In Qingnan Sag

Qingnan sag is located in Dongying Sag,its exploration area is approximately 300km2,the main exploration target segment which is sub-paragraph four on the sand,sand subparagraph four on the presence of a number of different sets itself the development of depositional systems,leading to the development of a variety of different sedimentary facies,resulting in many different types of reservoirs,reservoir characteristics make the sand on four sub-segments is very complex,and thus make oil and gas exploration conditions become complicated,affecting further oil and gas exploration.To solve these problems,the integrated use of sequence stratigraphy,sedimentology,reservoir geology,petroleum geology theory and technology,for different types of reservoir have different mechanisms,different types of reservoir characteristics and different reservoirs of Q ingnan sag exploration work Hydrocarbon Accumulation systematic research.The results show that,for the Q ingnan sag Upper Section of 4th sandbody types identified four kinds of sedimentary facies,11 kinds subfacies;near Q ingtuozi raised actic,nearshore subaqueous fan and fan delta development which,which,in close proximity to the southern ramp zone Guangrao raised in the north,are developed delta deposition.A clear change in the deposition and distribution longitudinal section and deposition plane.Qingnan sag sand submember on four main reservoir for the dam sandstone shallow lake shore.Reservoir space types are mainly primary porosity,which mixed with a small amount of secondary porosity development and fractures;small amount of dissolution and metasomatism.According to sedimentary facies division,Qingnan sag fan-delta and delta development-high porosity and permeability reservoirs,shore shallow lake dam development wells permeability reservoirs,nearshore subaqueous fan development Extra Low Porosity and Permeability Reservoir.Qingnan sag with good reservoir and cap,the main oil-bearing reservoir is shallow lake shore sand bar and some nearshore submarine fan reservoir,constructed from north to south presents-rock-reservoir distribution structure,de termine the reservoir properties of oil and gas production,oil and gas fan-delta and delta highest capacity,followed by beach sand dam reservoir capacity,nearshore subaqueous fan and gas production to a minimum.