The Study Of The Connectivity Of Sand Bodies Of Hutubihe Formation Reservoir Of Well Block Dixi-12 In Junggar Basin

The Well Block Dixi-12 is located in the central of Junggar Basin.The Cretaceous Hutubihe formation reservoir which in the Well Block is a small sandstone reservoir with low abundance and middle shallow layer.At present,the effect of water injection development is not obvious in the research reservoir,which has a serious impact on the development of the oil field that needs a fine description of the characteristics of oil-bearing sand bodies.Based on the literature search and combining the previous research achievements,this paper study on the stratigraphic correlation,distribution of sedimentary facies,reservoir sand distribution,oil sand overlay and connectivity by using the regional geology,well logging,seismic,core analysis and dynamic production data,and verified by the production dynamic data finally.The results showed that: the Hutubihe Formation is divided into 2 series,14 substratas and 165 single-sand bodies in vertical,which is about 800 meters in the study area.The Hutubihe formation reservoir of the Well Block Dixi-12 is shallow water delta deposition,the study area mainly belonged to delta plain that included five sedimentary microfacies:distributary channel,natural levee,abandoned channel,crevasse fan and flood plaid;the main oil sand body is scale small and thin thickness,as the typical “single sand and single reservoir” characteristics;the oil sands is mainly located in the abandoned channel and crevasse fan microfacies,accounted for about 80 percent,and less located in the distributary channel,generally reflect the unconventional characteristics of the high water and the low oil;the reservoir sand body mainly has three kinds of genetic types,mainly include the distributary channel type,the abandoned channel type and the crevasse fan type,The internal injection-production correspondence and connectivity are better in the single oil sand body,but bad in the reservoir,because of the abandoned channel and crevasse fan sand body and the distributary channel sand body are not connected,formation of small scale reservoir,and form the “isolated” type reservoirs that is disconnected with each other in the study region.