Reservoir Characteristics Of Light Oil In The Group Chang6of Shan-156Wellblock, Erdos Basin

The key development zone of Shan-156Wellblock， Huachi—Nanliang area，located inthe southwestern Ordos basin， Huachi—Nanliang area is situated in Yishan slope， which isflat structure， and dense sandstone reservoirs. Group Yan chang6is the main section for thispaper study. The study has shown that the purpose of the study area Yan chang6mainlyincludes the semi deep—deep depositional system. A large area of the formation of sand bodytakes shape the distribution of effective sand banded，and single well-controlled reserves inorder to the low production for per well. Therefore， the reservoir characteristics of theresearch carried out on The key development zone of Huachi—Nanliang area of group Yanchang6has a very important significance for future exploration and development of naturalgas in the area.On the basis of abundant data and materials from drilling， logging， coring， oil test，production test， laboratory analysis of geological data，this papers studies theSedimentary Microfacies， Petrology， Physical Properties，characteristics of Pore structureof the group Yan chang6in the study area， and then the reservoir revaluation is made.Studies have shown that Chang6reservoir group overall in semi deep—deep subfacies，itdevelops three types of gravity flow of sandy debris flow deposits， turbidity current， andslump deposits. The mud of semi deep—deep micro facies is also more developed micromicro facies.The rock types of gas reservoir are mainly very fine—fine，and fine Lithicsandstone. Experienced compaction， cementation， metasomatism， erosion diagenesis，etc， the reservoir sandstone has reached the late priod of early diagenetic stage A and theearly period of late diagenetic stage B.and the types of porosity are mainly dissolute pore andresidual intergranular pore as the main gas storage space.Microfacies， sand body distributionand diagenesis is the main factor to controlling gas accumulation， and the most favorablereservoir sand is sandy debris flow deposits. The results show that the types of reservoir aremainly Ⅱ and Ⅲ. Basically，banding reservoir are abundance in sandy debris flow deposits，and turbidite. In the group Chang6，there are three sub layer high quality reservoir，especially group6-3layer contained the most， which is the most favorable of the three layergas-bearing section.