Study On Reservoir Forming Elements And Its Reservoir Control Of Putaohua Oil Layer In Talaha Area,Songliao Basin

Talaha area is located in the middle of the west of the central depression of Songliao basin.It is an area rich in oil and gas and has good exploration and development potential.However,limited by the understanding level and research means,there is relatively little research on reservoir control in Talaha area,which is mainly reflected in the lack of in-depth research on sedimentary sand body,caprock integrity and development characteristics of transport channel,which affects the in-depth oil and gas exploration in Talaha area,resulting in unclear oil and gas exploration direction in Talaha area.Therefore,based on the systematic analysis of the characteristics of oil and gas accumulation elements in five aspects:source rock,reservoir,cap rock,trap and transport channel,combined with the accurate description of oil and gas reservoir types and oil and gas distribution characteristics,this paper studies the reservoir control effect of oil and gas accumulation factors of Putaohua oil layer in Talaha area,and further predicts its favorable target of oil and gas accumulation.The achievements obtained in this study mainly as follow:（1）The source rock of the 1^stmember of Qingshankou Formation in Talaha area is the main oil and gas generation and drainage layer,and the southeast is the main oil and gas generation and drainage area;The reservoir characteristics of each oil formation of Putaohua oil layer are general,the sand bodies are poorly developed,and the reservoir physical properties are good;The caprock characteristics of each oil formation of Putaohua oil layer are poor,the thickness of mudstone cap rock is small,and the lower limit of juxtaposition thickness required for sealing oil and gas does not exist;There are 50 structural traps and 9 micro amplitude structures in T_1-1 reflector;T_1-1 reflector defines 25 oil source faults and 39 dominant transport channels of oil source faults;There are 16,12 and 13 dominant transport channels of sand bodies in PI3,PI2 and PI1 oil formations respectively.（2）Putaohua oil layer in Talaha area develops five types of oil and gas reservoirs:fault anticline,fault block,fault nose,fault shielding and fault lithology;Putaohua oil layer has good oil and gas bearing property.Oil and gas flow wells are mainly concentrated in the south and north central of Longhupao anticline structural belt and the south edge and north central of Talahai fault zone.（3）The reservoir controlling effect of oil and gas accumulation elements in Putaohua oil layer in Talaha area is mainly as follows:The lower limit of sand to ground ratio required for oil and gas reservoir sand body is 0.15,which controls the range of oil and gas accumulation;Distributary channel and turbidite fan sand body control the area of oil and gas accumulation;The oil source fault and the dominant transport channel of sand body control the position of oil and gas accumulation.Oil and gas are mainly distributed within 2.6km away from the oil source fault and 2.0km away from the dominant transport channel of sand body.（4）Putaohua oil layer in Talaha area has predicted 15 favorable targets for oil and gas accumulation,with a total area of 39.92 km².The above research achievements can provide a reference basis for the next stage of oil and gas exploration and development of Putaohua oil layer in Talaha area.