The Evaluation Of Chang 9 Shale Gas Reservoir Characteristics In The South Of Ordos Basin

The study is based on the reservoir of Chang 9 formation,the south of Ordos Basin.By collecting and researching the large number of geological data in the study area,and making full use of field outcrops,drilling,logging,and thin section analysis data,SEM,organic geochemistry and a variety of analysis methods,the paper studied the comprehensive evaluation and the reservoir characteristics of Chang 9 formation,the south of Ordos Basin.Delta and lacustrine sedimentary facies are recognized from the Chang 9 interval in the study area.The thickness of dark mud shale in the study area is large,and the distribution is stable.By using the lithology,lithofacies and X-ray diffraction of whole rock analysis,we have found out that the dark mud stone of Chang 9 formation is mud,muddy siltstone,silty mudstone.Brittleness mineral content is 61.5%.The dark mudstone of Chang 9 formation contain high organic matter.Organic carbon content is 1.0-3.5%.Type of Kerogen is ?.Vitrinite reflectance is 0.6-1.2 %.By scanning electron microscopy,Chang 9 shale pore types are residual intergranular pores,intragranular dissolved pores and intracrystalline pores.Chang 9 shale porosity distribution is 1%-3%;penetration is less than 0.01 × 10? 3?m2.More exploration wells in the study area in the Chang 9 shale gas test show abnormal.Drilling coring measured gas content is more than 1m3/t.The gas content is affected by multiple factors.According to the conditions of shale gas accumulation,and the standard of shale gas reservoir evaluation,this paper is using the three parameters: the thickness of dark mudstone,total organic carbon and organic matter maturity and other related parameters to predict the favorable target area of shale gas in Chang 9 formation,and provide the reference to the exploration and development in other regions.