Reservoir Characteristics And Analysis Of Reservoir Formation Conditions Of Upper Cretaceous Qingshankou-Nenjiang Formation In Songliao Basin Changling Area

Songliao basin is a large meso-cenozoic continental petroliferous basin in China.It is an extensional rift-type basin with a North-East distribution.It is located in the northern section of the Pacific rim tectonic domain and the eastern end of the palaeozoic xingmeng geosynclinal fold belt.The tectonic evolution of changling exploration area,which is located in the south of the depression in the central zone of songliao basin,is divided into four stages: fault depression stage,fault depression transformation stage,fault depression stage and tectonic inversion stage.The structure of depression strata in changling exploration area is relatively simple,which is generally manifested as east-west strike-off,which is mainly controlled by the background of tensile stress and has the characteristics of tension and torsion locally.Its structural evolution has the characteristics of typical back-arc basins.Up to now,industrial oil flow has been found in quantou formation,qingshankou formation,yaojia formation and nenjiang formation of depression strata in changling exploration area,the qingshankou formation as the main oilfield reservoir in the Yaoyingtai and Suotu Oilfield;the industrial oil flow in the nenjiang formation of YN5 well is obtained,which makes nenjiang formation an important field for increasing storage and production in the near future.Although the exploration results of depression strata are fruitful,the exploration in recent years is not ideal due to the restriction of insufficient research on reservoir forming conditions and insufficient understanding of main controlling factors.Therefore,based on the study of oil and gas geology,such as structural structure,sedimentary reservoir,effective source rock and transmission system,this project focused on the typical reservoir anatomy,so as to clarify the characteristics of reservoir formation and main control factors,and finally provide the basis for well location demonstration.Through seismic interpretation,the structural characteristics of the overlying strata in the east,steep strata in the east and slow strata in the west are recognized.Emotion through the analysis of tectonic evolution,think big bump is a controlled by basement buried hill of palaeostructure,depression period evolved into low bulge,the black temple concave is a inheritance sag,negative amplitude decreases in the depression period,yanshan ? and Himalayan tectonic movement after extrusion.Composite rock,electric and seismic data to carry out the depression layer stratigraphic classification and correlation of exploratory well,building regional stratigraphic framework section,has been clear about the various formation strata distribution characteristics,on the basis of previous studies,carried out Qing I,Nen I&II hydrocarbon source rocks on the effectiveness of using geochemical index,further implement the distribution range of effective hydrocarbon source rock.In sedimentary reservoir research,using the petrology characteristics,the sand ground than the data,such as granularity data in the provenance analysis,combined with the set process such as core,logging,well logging,the comprehensive analysis and research the related data material and the core of the view that,depression layers of sedimentary system in the region made a fairly detailed research,divided into the single well facies;The plane facies of key target strata are characterized according to single well facies,sand-ground ratio and seismic equivalence.Studies suggest that in the period of ?Sand group Of Qing 1 Section,the main development half deep lake-deep lake facies;in the period of ? Sand group Of Qing 2 Section,the main body of the Midwest is delta front facies.In terms of the study on the transport system,the transport characteristics of sand bodies and faults are analyzed: three-dimensional zone fault activity studies are mainly carried out.The hydrocarbon source faults active in sifang tai-ming water period are beneficial to the vertical migration of oil and gas in qingshankou formation,while the hydrocarbon source faults active in Ming water period are beneficial to the vertical migration of oil and gas in yaojia and nenjiang formation.The study of sand body transport shows that skeleton sand body and structural ridge are efficient channels for oil and gas lateral migration in qingshankou formation over long distance.Based on the analysis of reservoir characteristics,typical reservoir anatomy,failure well analysis and other main control factors of reservoir formation,it is concluded that the study of main control factors of reservoir formation shows that the transmission and trap effectiveness control of qingshankou formation reservoir in central and western China;The formation and distribution of oil reservoirs in yaojia formation and nenjiang formation are controlled by the distribution of hydrocarbon source,fault and sand body.Based on the above studies,Qingshankou Formation has the potential of expanding exploration space outward,while Yaojia Formation and Nenjiang Formation have the most favorable exploration zones in the Suotu,Beizheng and Yaoyingtai areas.