The application of sterane in the oil-sources correlation of near-source and multi-source: a case study of CH-8 oil reservoir in Central Ordos Basin, China

CH-8 oil reservoir holds the characteristics of near-source and multi-source in Ordos Basin, China. The sterane is one of the effective biomarkers in the study of oil-source correlation. The research results show that the parent material source and maturity degree of source rocks (CH-7, CH-9 and CH-10) and crude oil (CH-8) are similar. At the same time, the diasterane parameters of DiaC27 beta alpha(20S + 20R), DiaC28 beta alpha(20S + 20R) and DiaC29 beta alpha(20S + 20R) can distinguish the source rocks into 5 types with great result, including CH-7, CH-10, CH9-WQ, CH9-HXK and CH9-SN. In addition, the dominated source of CH-8 crude oil is CH-7 source rock, the CH9-WQ source rock may make a small amount of contribution and the other of source rocks have little contribution to CH-8 crude oil in Shanbei area of Ordos Basin, China.