Geochemical characteristics of biomarkers of source rocks from Taipinglinchang formation in Sunwu Jiayin Basin

Key words:  Sunwu Jiayin Basin  Early Cretaceous  source rocks  biomarkers

Abstract:

The geochemical characteristics of black mudstone from the lacustrine facies in Taipinglinchang formation, Sunwu Jiayin Basin were researched by gas chromatography and gas chromatography mass spectrometer. The results indicate that the content of soluble hydrocarbon in the black mudstone from Taipinglinchang formation has reached the source rocks standard,with high content of soluble hydrocarbon in the group composition, high ratio of saturated/aromatic hydrocarbons and good organic type. The both properties of the n pentane and the biomarkers demonstrate the characteristic of prematurity low maturation of source rocks. The organic material of source rock possesses character of the mixed parent material, with the rich content of thallophyte in the organic sources. The source rocks deposited and preserved in the reductive weakly reductive circumstance with high salinity. The water with chemistry stratify is better for burial and preservation of organic material, which can provide material foundation for the oil and gas forming in Sunwu Jiayin Basin.