Oil Resource Evaluation Of Chang 9 Hydrocarbon Source Rock In South Central Ordos Basin

Chang 9 member is strategic successive strata in the further petroleum exploration of the Ordos Basin,and further hydrocarbon source rocks researches on this layer can direct the future exploration of the Basin.In this paper,the hydrocarbon source rocks are qualitatively evaluated by means of organic geochemistry analysis with drilling and logging data.The distribution characteristics of source rocks are studied by calculating TOC.The genetic method and hydrocarbon generation rate method are used to calculate the amount of hydrocarbon source rock resources.The results show that:By using GR curve to calculate the argillaceous content to divide mudstone,it is concluded that the overall distribution of mudstone is north west,and the place with large thickness is located in DingBian WuQi area.Through fitting calculation of TOC,it is concluded that the plane distribution trend of organic carbon content in chang9 source rock is north west,which has a good correlation with the distribution of mudshale thickness.Through qualitative evaluation of source rocks,it is found that source rocks have high organic matter abundance,good type and moderate maturity,and are qualified for hydrocarbon generation.Through quantitative evaluation of source rocks,the thickness contour map of source rocks was drawn,and the thickness of source rocks in dingbian-wuqi generation was known.The hydrocarbon generation was(37.25~49.95)×10~8t and the oil resource was(1.97~2.64)×10~8t in the study area,according to the calculation of the genetic method and hydrocarbon generation rate method.