The Research Of Regularity Of Hydrocarbon Enrichment And Tectonic Evolution In Lixian County Slope

Lixian County slope is located in the western of Raoyang depression,in the Northeast-Southwest direction,is a secondary tectonic unit in Raoyang depression,have rich oil and gas resources.As exploration extent advances,the exploration direction turned to structural-lithologic oil and gas reservoirs.In terms of geological research,the main controlling factors of the formation with various reservoir in the slope is not clear;accumulation mechanism and accumulation law of all kinds of oil and gas need to be studied.This thesis is based on the modern theories of structural geology,and use method of seismic interpretation,structural analysis,balanced cross section,Allan profile diagram,mud stone smearing coefficient,comprehensive research of hydrocarbon accumulation condition to summarize the geological characteristics and analyze tectonic evolution,combined with the conditions of source reservoir caprock assemblage to analyzed the migration and accumulation law of reservoir.draw the following understanding and conclusion:1,fracture system of Lixian County slope has obvious substage and zonation,it can be divided into early prosperity-early decline,early prosperity-late decline episodic activity and late prosperity-late decline three types.The fracture of early prosperity-early decline type are mostly distributed in the north of the slope,as fracture of early prosperity-late decline type are distributed in the middle slope area,while the late prosperity-late decline type are regional distribution.2,the tectonic deformation of Lixian County slope is controlled by the Raoyang sag,its tectonic evolution can be divided into three stages.Kongdian formation,shanejie formation and dongying formation sedimentary period of paleogene system constitute the fault depression period,Neogene Guantao formation and Minghuazhen Formation sedimentary period for the depression period,the Quaternary plain group sedimentary period for the region thermal subsidence period.3,lateral and vertical sealing of Gaoyang fault is well,and it has powerful ability in sealing oil and gas,also make the oil and gas which migrate so far present by contiguous distribution.The lateral and vertical sealing of Dabaichi fault is weaker than Gaoyang fault,the oil and gas could through the Dabaichi fault and gathered near the Gaoyang fault,also make the oil and gas present the Beaded distribution near the Dabaichi fault.4,the complex reservoir distribution characteristics of "high water and low oil" in the Central South of the study area is the early stage oil and gas get into the shallow layer,and then through the connected sand body migrate gradually to the slope.5,set up the oil and gas accumulation model of central-southern in Lixina County slope: the oil source of shayixia formation of Suning depression through the fault and unconformities which in slope inner belt migrated to the shallow stratum.And then through the each layer connected sand body migrated to the upper part of slope.And finally accumulated near the dabaichi and Gaoyang fault.Formed fault-nose dominated structures or structural-lithologic reservoir.The northern area mainly developed consequent fault docking and multiple oil supply accumulation model.