Biomarker Characteristics and Hydrocarbon Generation Potential of Hydrocarbon Source Rocks from the Yanchang Formation in the South Ordos Basin

In order to study the hydrocarbon potential of the different layers and lithological source rocks in the South Ordos Basin,various types of samples were collected,geochemical experiments were carried out and contrasted.The results showed that the source rocks in the research area can be divided into five types,A1,A2,A3,A4and B,each of them has different distribution characteristics,forming environment and hydrocarbon potential.The source rock A1(oil shale from Chang 7Formation)is the main source rocks with high hydrocarbon generation potential,the source rocks A2and A3(mudstones from Chang 7and Chang 8Formation)are the secondary source rocks,whose hydrocarbon generation potential is low,the source rocks A4and B(thin mudstones surrounded with thick sandstone)have poor hydrocarbon generation potential,are poor hydrocarbon source rocks.