塔里木盆地塔中隆起寒武系深层油气地球化学特征及成因

发布时间：2018-05-15 06:14

  本文选题：天然气类型 + 油气源　； 参考：《石油与天然气地质》2017年02期

【摘要】：塔中隆起寒武系碳酸盐岩储层油气资源丰富,然而由于复杂的构造地质背景,油气来源和天然气类型还存在较大争议。通过详细分析ZS1井、ZS1C井和ZS5井寒武系不同层段中凝析油和天然气的组成、碳同位素等特征,并结合寒武系-下奥陶统与中、上奥陶统烃源岩地球化学特征,对其油气来源和天然气成因类型进行了判别。研究结果表明,该区天然气为典型的腐泥型干酪根裂解气,其中寒武系肖尔布拉克组天然气干燥系数大于0.98,N2含量介于2.5%~4.0%,为过成熟干气,且凝析油族组分与和饱和烃单体烃碳同位素偏重,nC_9—n C20碳同位素介于-28.8‰~-26.3‰,表明油气来源为寒武系-下奥陶统烃源岩。而寒武系阿瓦塔格组和吾松格尔组天然气干燥系数介于0.63~0.78,N2含量介于0.2%~0.8%,为低成熟湿气,且凝析油族组分和饱和烃单体烃碳同位素相对较轻,nC_9—nC_(23)碳同位素介于-37.25‰~-32.56‰,表明油气来源为中、上奥陶统烃源岩。
[Abstract]:Cambrian carbonate reservoirs in the Tazhong uplift are rich in oil and gas resources. However, due to the complicated tectonic geological background, the source of oil and gas and the types of natural gas are still controversial. The composition of condensate oil and natural gas, carbon isotopes in different Cambrian formations of ZS1 well ZS1C and ZS5 well are analyzed in detail, and the geochemical characteristics of Cambrian-Lower Ordovician and Middle Ordovician hydrocarbon source rocks are combined. The origin of oil and gas and the genetic type of natural gas are distinguished. The results show that the natural gas in this area is typical humic kerogen cracking gas, in which the natural gas drying coefficient of Cambrian Shaubrak formation is greater than 0.98N _ 2 and the content of N _ 2 is between 2.5 and 4.0, which is overmature dry gas. Moreover, the hydrocarbon isotopes of condensate group and saturated hydrocarbon monomers are between -28.8 鈥，

本文编号：1891306