八屋油田原油饱和烃组成特征及其意义研究

Biomarker Characteristics and Significance of Crude Oils of Bawu Oilfield

运用色谱质谱技术（GC—MS）分析系统对八屋油田原油饱和烃的地球化学特征进行了研究。显示全烃主峰碳大多为nC21、nC23，C29甾烷比C27甾烷占优势，揭示了八屋油田原油母质来源以高等植物为主；Pr／Ph值介于0．6～1．3，G／C30H值介于0．3～1．1，表明该油田原油发育于还原-弱氧化微咸水-咸水环境的烃源岩；C29-αββ／（ααα＋αββ）和C29-20S／（20S＋20R）等成熟度参数说明原油处于成熟阶段。根据其母质来源、沉积环境和成熟度的不同，认为八屋油田BK60区块、SN54区块、八屋其他地区原油为不同成因类型的3种原油。

The geochemical characteristics of saturated hydrocarbon from Bawu Oilfield are systematically analyzed by GC-MS,the main peaks of total hydrocarbon are almost nC21and nC23,apredominance of C29sterane over C27sterane indicates stronger contribution of higher plant.The Pr/Ph values(between 0.6and 1.3)and the gammacerane values(between 0.3and 1.1)show that oils are originated from the source rock developed in reduction-weak oxidizing brackish water-salt water environment; the maturity parameters of C29-αββ/(ααα+αββ)and C29-ααα20S/(20S+20R)illustrate that the oils are at mature stage.According to the differences of parent material source,sedimentary environment and maturity,the oils of Block BK60,SN54section and the others blocks are three different genetic types of crude oils.