Paleozoic oil–source rock correlations in the Tarim basin, NW China

• Published in: Organic geochemistry Vol. 31; no. 4; pp. 273 - 286
• Main Authors: Zhang, S.C, Hanson, A.D, Moldowan, J.M, Graham, S.A, Liang, D.G, Chang, E, Fago, F
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2000; Elsevier Science
• Subjects: 24-isopropylcholestanes; Cambrian; Carboniferous; China; Dinosteranes; Earth sciences; Earth, ocean, space; Exact sciences and technology; Hydrocarbons; Norcholestane; Ordovician; Sedimentary rocks; Stratigraphy; Tabei; Tarim basin; Tazhong; Triaromatic dinosteroids; Xinjiang China; Far East; China; Tarim Basin; 24-isopropylcholestanes; Dinosteranes; Norcholestane; Cambrian; Tazhong; Tabei; China; Carboniferous; Tarim basin; Ordovician; Triaromatic dinosteroids; gas chromatograms; petroleum accumulation; biomarkers; source rocks; mass spectra; concentration; Paleozoic; Asia; upper Paleozoic; lower Paleozoic; wells; petroleum; organic carbon
• ISSN: 0146-6380; 1873-5290
• DOI: 10.1016/S0146-6380(00)00003-6

We studied a suite of 40 oils and extracts of purported source rocks from the Tarim basin in NW China. The main group of oils comes from Tazhong and Tabei wells, which sample the largest known petroleum accumulations in the basin. These oils can be statistically correlated with extracts of Ordovician rocks based upon high relative concentrations of 24-isopropylcholestanes and low relative concentrations of dinosteranes, triaromatic dinosteroids, and 24-norcholestanes. In contrast, extracts from Cambrian rocks have low relative concentrations of 24-isopropylcholestanes with high relative concentrations of dinosteranes, triaromatic dinosteroids, and 24-norcholestanes. Although some Tarim basin Cambrian rocks yield high total organic carbon contents, we see little evidence in the analyzed oil samples to suggest that they came from Cambrian source rocks.