Application of controlled source audio magnetotelluric sounding in oil shale exploration

With the rapid increase of people's demand for oil and gas,oil and gas exploration and development from high-quality oil and gas to the poor-quality and difficult mining and higher costs oil and gas,from petroleum-based conventional oil and gas to a gradual increase in unconventional oil and gas,there may be achieved conventional and unconventional oil and gas situation simultaneously in the near future. Oil shale refers to a dense organic-rich sedimentary rock kerogen with ash content of 33%,which is a form of unconventional oil and gas. The shale oil is obtained through processing oil shale,similar to natural light petroleum,after hydrocracking refining,getting gasoline,kerosene,diesel,paraffin and other chemical products. In order to find oil and gas resources to succeed,the distribution of oil shale in Weibei Tongchuan region is studied using controlled source audio magnetotelluric sounding method through the analysis of Ordos Basin related oil shale geology and drilling data,providing the basis for oil shale exploration. Distribution of oil shale horizons is mainly Mesozoic in Weibei and Shanbei region of Ordos Basin,including Jurassic Yan'an group,diazepam group,Triassic Yanchang group( chang1,chang7,chang9) and so on. Among them,the second upper oil shale of Triassic Yanchang group( chang7) is wide distribution with large thickness and high oil content. It can form large oil shale deposits,so the purpose of the work is chang7 horizons.