A Study On Distribution Of Oil Reservoir In X Area Of Ordos Basin

In order to study the reservoir distribution of X area in Ordos Basin,the Chang 4+5 and Chang 6 oil reservoirs are mainly studied in this paper.Based on a lot of exploration results about study area,using geology,sedimentary petrology and reservoir synthesis and evaluation,combining with other subject knowledge and methods,reservoirs are divide and compared,the stratigraphic,tectonic and sedimentary characteristics of the reservoirs are analyzed,and then the reservoir distribution rules and controlling factors which effect it are summarized.With the conclusion of this paper,the geological basis for the next step of efficient development of X area reservoirs is finally provided.The main conclusions we obtained through this study are as follows:?1?The structure of study area is a monoclinic structure which higher at east,while lower at west.?2?During the sedimentary periods of chang6₁ and chang6₂ sections in the study area,there were mainly underwater distributary channels and underwater natural dike sedimentary microfacies.In addition to the underwater distributary channel,the sedimentary microfacies of estuary dam are widely developed in the 4+5₂ member.?3?After strong compaction and cementation,the Chang 4+5 and Chang 6 reservoir in study area are mainly deposit with gray fine-grained feldspar sandstone.According to the reservoir classification evaluation table,Chang 4+5 and Chang 6 reservoirs in this area are mainly correspond to reservoir grades of IIIb and IVa.?4?Chang 4+5 oil layer is mainly developed in stable sand dam;while Chang 6 oil layer is at the top of the sand body.The factors controlling Chang 4+5reservoir development are sedimentary phase and reservoir properties.While factors mainly affect Chang 6 oil reservoir are reservoir type,development of sand strata and preservation condition of reservoir.