渤海海域中西部地区气藏伴生油地球化学特征和油源研究

通过碳同位素与色谱质谱分析,探讨了渤海海域中西部地区气藏伴生油的碳同位素与生物标志物地球化学特征,依据4-甲基甾烷和伽马蜡烷含量,将气藏伴生油分为3类,再结合源岩的地球化学特征,对气藏伴生油进行了油源研究。研究表明,气藏伴生油多数属于高蜡油,补身烷分布一致,三环萜烷丰度较低,甾烷组成具有较好的相似性,但伽马蜡烷、4-甲基甾烷分布有差异。油源对比结果表明,气藏伴生油主要来源于沙河街组烃源岩,东下段烃源岩也有贡献。

Geochemistry and Source of Oil Associate with Gas Reservoirs in the Western Bohai Bay Basin

Through carbon isotope and GC-MS analyze, carbon isotope and biomarkers geochemistry of oil associate with gas reservoirs has been researched in the western of the Bohai Bay Basin.Then in terms of the content of 4-methyl sterane and gammacerane,oil associate with gas reservoirs is divided into three types;at the same time,associated with geochemistry of source rock,the source of the oil associate with gas reservoirs has been researched.The research indicated that oil associate with gas reservoirs mainly belongs to high wax oil,most of which the distribution of drimane and the consistent of sterane are similarity,the abundance of tricyclic terpane is lower except the distribution of 4-methyl sterane and gammacerane has differences.The results of oil and source correlation show that oil associate with gas reservoirs is mainly derived from the source sock of Shahejie Formation.