摘要
库车坳陷迪北地区具备良好的油气成藏条件,拥有丰富的油气资源,然而对于该地区油气来源的认识还存在一些问题。通过利用GC-MS（气相色谱/质谱法）对迪北地区烃源岩生物标志化合物特征进行了分析。研究结果表明：迪北地区烃源岩生物标志化合物中正构烷烃、C29ααα20S/20（S＋R）、C31αβ22S/（22S＋22R）和C32αβ22S/（22S＋22R）比值特征显示,该地区烃源岩主要处于成熟演化阶段;C27-C29甾烷分布特征表明,迪北地区烃源岩母质主要来自于陆源生物有机质的输入;Pr/Ph、重排甾烷∑C27/规则甾烷∑C27比值、三环萜烷分布特征、C30霍烷、Tm、Ts及伽马蜡烷丰度等分布特征,总结出迪北地区烃源岩主要为淡水-微咸水的弱氧化沉积环境下形成的陆相烃源岩。由此可知,通过对迪北地区烃源岩生物标志化合物特征分析发现,迪北地区烃源岩成熟度较高,主要为弱氧化沉积环境下形成的陆相烃源岩,且研究成果将有助于迪北地区的油气成藏研究。
The Dibei area in Kuqa Depression has good hydrocarbon accumulation conditions and is rich in oil and gas resources. However,some problems are still existed about the understanding of the oil and gas source in this area. The biomarker compound of source rocks in Dibei area was analyzed by GC-MS. Comprehensive analysis of various biomarkers,such as the n-alkanes,C_（29）ααα20S /20（ S ＋ R）,C_（31）αβ22S /（ 22 S ＋ 22R） and C_（32）αβ22S /（ 22 S ＋ 22R） ratio,shows that the source rocks in Dibei area is mainly at the low maturity-mature stage. Distribution characteristics of C_（27）- C_（29） steranes of source rocks reveal that organic matters of source rock in Dibei area are mainly derived from terrestrial higher plants and creatures. ∑ C_（27） diasteranes / ∑ C_（27） steranes,Pr / Ph,tricyclic terpanes distribution characteristics,Tm,Ts and the percentage of gammacerane indicate that the source rocks in Dibei area are continental hydrocarbon source rocks which were formed under the freshwater—brackish water weak oxidizing sedimentation environment. Therefore,the research results will be helpful to the hydrocarbon accumulation research in Dibei area.
出处
《科学技术与工程》
北大核心
2016年第13期29-34,41,共7页
Science Technology and Engineering
基金
国家科技重大专项(2011ZX05007-002)资助
