A Study On The Superimposed Relationship Of Sand Bodies Of The Fourth Member Of The A-member Of Ha 34 Block In Hanan Area

The H34 block in the South of Hanan area is located at the A'nan depression in Erlian basin.The fourth member of A'ershan Formation is one of the major oil-producing areas,experienced in the production and stable period,but the output has been declining in recent years,and it's more difficult to retain the stability.Because,the lack of the research on the spatial superimposed relationships and the heterogeneity of it,It is difficult to improve the recovery efficiency.Based on the study of formation refinement and sedimentary microfacies,this paper discusses the genesis,distribution regularity and the connecting relationship of sand bodies,probes into the spatial superposition of sand bodies,and finally uses the geochemical thought to assist in studying the connecting relationship of sand bodies in space:(1)According to the stratigraphic correlation logo and the control of the sedimentary strata cycle,divided the fourth member of A'ershan Formation intothree sand group from the bottom up,AIupper,AImiddle and AIlower.The AIupper sand group was divided into 1,2,3 single layers,AImiddle sand group is divided into 4,5 single layers.AIlower sand group is divided into 6,7,8 single layers,a total of 8 single layers.(2)Through the definition of rock facies logo,primary sedimentary structure logo,grain size analysis and logging logo,determine the two member of A'ershan Formation of the fan deltafront subfacies and the development of subaqueous distributary river channel,interdistributary bay microfacies.On the basis of determining the sedimentary background of the industrial area,the sedimentary microfacies of the single layer are divided and the characteristics of the microfacies distribution in the single layer are analyzed.(3)According to reservoir configuration thinking,we study in the rule of superimposed relationship between channel sand bodies,draw sand body connection diagram,divide the sand body superposition relationship into isolated,interlaced,tangent and superimposed(separated and connected).It is known from the picture which the most of the sand bodies in the work area are in the superposition type,which are isolated and interlaced in turn.(4)Combination with geochemical theory and gas chromatography fingerprint technology,we can see the correlation between H34-21 and H34-23 is the best,the most of the sand bodies are connected superposition.H371 is in poor correlation with other wells,and most of the nearby sand bodies may be in a separate superposition.