Study On Sedimentary Facies And Favorable Zone Prediction Of The K₁d-K₁q₁ Of The Dehui-lanjia Area In The Dehui Fault Depression

In this paper,the geological situation of Dehui fault depression in the area is complex,there has been a great influence on sedimentary facies study and prediction of favorable region,in order to find out the distribution rule of oil and gas,to provide basis for exploration and development in the future.The sequence stratigraphy of the study area is divided according to the Stratigraphic sequence Division scheme of Songliao Basin.The sedimentary facies and sedimentary systems are studied by combining the geological background and drilling and seismic data of the research area on the basis of Sequence division,and then the evaluation criteria of favorable zones are established by using sedimentary facies and sandstone thickness,and favorable zone zones are predicted.The research shows that by establishing a sequence stratigraphic framework,we divided the target layer of the study area into two SSQ4,SSQ5.SSQ4 further divided into three three sequence SQ7,SQ8,SQ9,respectively,K1d2,K1d3,K1d4,SSQ5 further divided into two three-level sequence SQ10,Sq11,SQ10 corresponds to K1q1 and K1q2,SQ10 further divided into the water system and the water retreat system threshold,the water entering system field corresponds to the k1q1;On this basis,the 16 coring wells in the research area are observed and described,and combined with the logging and seismic data of 48 wells are combined to establish the core-log facies model,A total of 4 phases of 8 subtypes of 14 microfacies of the target layer were identified,through further analysis of the profile and plane phase,it is concluded that in the sedimentary period of the K1 d,the basin enters the fault-depression transition period,gradually becomes more and more narrow,the distribution range of lake basin is reduced,the lacustrine phase is gradually extinct,and the whole region is basically dominated by the braided Delta Plain.,the whole area of the K1 q was changed into fluvial facies,and the lower part of the K1q1 was braided River facies,and the upper part of the K1q1 was curved stream facies.Based on the criteria of sedimentary facies and sandstone thickness,the advantageous zone of the research area is divided into three groups according to the evaluation conditions.