刍云深水凹陷高成熟原油芳烃地球化学特征研究

对白云凹陷采集的27个原油样品的芳烃组成进行了系统的研究。其分布特征和相对含量表明，原油母质具明显的陆源高等植物输入特征，沉积环境以氧化环境为主，根据萘系列、菲系列、二苯并噻吩系列化合物的相对含量分布差异，优选有效的烷基萘、烷基菲、烷基二苯并噻吩成熟度指标，综合分析了白云凹陷原油成熟度特征。原油总体属于成熟一高成熟原油，结合生物标志化合物组成可划分为A、B两类，A类原油的成熟度高于B类原油。还选用有效的成熟度参数探讨了白云凹陷油气运移规律，如三甲基萘比值，该参数指示油气运移方向沿白云主洼中心向周围运移，且邻近番禺低隆起，运移方向由西向东，即沿着成熟度由高到低方向运移。

Study on geochemical characteristics of aromatic hydrocarbon of high-maturity crude oils in the Baiyun deep-water Sag

The aromatic compound characteristics of 27 crude oil samples collected from the Baiyun Sag were studied. The distribution and relative content of the aromatic fraction indicate an oxidizing type of depositional environment, with a notable higher plant input. Alkyl-naphthalene, alkyl-phenanthrene and alkyl-dibenzothiophen, are found to be optimal parameters for assessing thermal maturity characteristics of crude oils in the Baiyun Sag. The crude oils show mature-high mature oil characteristics. By using aromatic fraction in conjunction with biomarker compounds, the crude oil can be divided into two classes： A and B. Class A has a high maturity compared to B. In this study, aromatic maturity parameters that are effective in accessing oil and gas migration mechanism are discussed, for i.e. TMNr indicates migration direction along the center of the Baiyun main depression to its surroundings; and adjacent to Panyu Lower Uplift, oil migration is from zones of high maturity in the west to zones of low maturity in the east.