Study of OilSource Correlation for Tahe Oilfield of Tarim Basin

Key words: 
• Tahe Oilfield /
• crude oil and source rocks /
• biomarkers /
• oilsource correlation

Abstract: Tahe oilfield of Tarim basin is the largest oilfield found in Paleozoic marine carbonate in China so far. However, its oil source is not still ascertained. In this paper, geochemical compositions of the crude oils of Tahe oilfield and CambrianOrdovician source rocks were studied, and oil source correlation was carried out. The compositional and distributional characteristics of nalkanes, isoprenoid hydrocarbons, steranes and terpanes in crude oils and source rocks indicate that the studied crude oils are closely related to CambrianOrdovician source rocks. This is identical with the geological fact that Tahe oilfield has undergone the longterm and multiperiod accumulation process which permitted the CambrianOrdovician source rocks to continuouslly supply crude oil for the oilfield. This result still shows that the difference in biomarker compositions between the crude oils from Tahe oilfield and CambrianOrdovician source rocks may be related to the contribution of these biomarker compounds originated from different evolutionary stages of organic matter. This should be paid special attention to study the correlation of oil and source rock with high maturity.