Thermal Evolution Characteristics and Significance of Source Rocks in Xingouzui Formation in Xingou Area

The Tmax of rock pyrolysis,the colour of sporopollen,the maturity of biological marker,and the reflectance of vitrinite are measured with the analytical method for organic geochemistry.Systematic analysis of the thermal evolution of the source rocks in Xingou area indicates that the source rocks are distributed mainly within the immaturity range;The vitrinite reflectances are between 0.5%and 0.6%,and the source rocks are all in the stage of immaturity and can only produce immature oil.The study also revealed that the oil produced from Xin-1Block and Xin-2Block is immature or low mature one,implying that the produced oil in Xingou area may include both the immature oil at local place and the mature oil from external source rocks.