The Research Of Hydrocarbon Accumulation Regularity And Main Controlling Factorsin The Slope Of Rift Basin

Based on the structural geology,petroleum geology and sequence stratigraphy theory as the theoretical basis,through the comprehensive utilization of seismic,logging and core data,combined with regional tectonic and sedimentary background,We have divided sag Wudong slope layer is into 2 regional marker beds(standard when the surface)and 5 local marker(reference isochron surface);comprehensive logging and seismic data,the area of incised valley region of the tracking area,think Wudong slope South formation suffered two downcutting,formed two incised valley,incised valley north-south banded distribution;and Ulson oil cut development stage three sedimentary Valley,the first cutting sedimentary valley of detrital material,but not be incised valley fill.Second downcutting filling second detrital material;thereafter,incised valley formed two erosion and filling third detrital material("three deposition").Combined with the tectonic evolution history and fault activity period,the Ulson depression Nantun Formation is divided into 4 sets of fault systems:early extensional fault system,middle tensional-shear fault system,early extensional middle tensional-shear fault system and early extensional fault system middle tensional-shear late inversion.Fault 2 fault system belongs to the long-term activity after early extensional fault system,is connected with the bridge middle tensional-shear fault system and link.Fine reservoir anatomy shows,Ulson oil field south of a reservoir has a fault block reservoir,fault-lithology composite reservoir,erosion unconformity screened reservoir,lithologic reservoir and microstructure of 5 kinds of reservoir,and the types of reservoir with geological characteristics,the respective oil water distribution rules and controlling factors of hydrocarbon accumulation are the respective the distinctive features of.On this basis,think Ulson oil field south of a period of oil and gas enrichment is mainly controlled by 7 factors:the NE and nearly EW reverse fault larger scale control block;② north-south or NNE reverse small elongation control local;③ north-south strip of cloth cutting exhibition Jinshun source of sand control block valley;④ erosion unconformity can be used as a shield control local;the lithologic control local;favourable places for the tiny structure as the accumulation of oil and gas control part;the oil source control accumulation range("seven control factors.").Finally think Wudong slope development of three kinds of oil and gas accumulation model:(1)the reverse fault\/micro amplitude type oil and gas pool-forming model;(2)migration of fault and unconformity reservoir forming mode of oil and gas shielding;(3)and accumulation pattern of transporting faults and sandstone lens type oil and gas.