摘要
针对塔里木盆地东部英南2凝析气藏不同产层中气体组分和甲烷、乙烷碳同位素分析,探讨了天然气运移成藏过程中,由于地色层作用,组分发生的分馏现象,表现在甲烷相对重烃、异构丁烷相对正构丁烷优先运移,逸散出去的轻烃(甲烷)在上覆盖层砂岩致密性发育过程中逐渐被细菌利用,使天然气组分逐渐贫化甲烷;随深度变浅天然气的δ13C1和δ13C2值变重,上述地化参数示踪了盖层致密性发育过程中天然气组分的分异现象。
The natural gas migration and reservoing process of Yingnan-2 condensate gas field is discussed in the paper according to the gas component and methane/ethane i sotope analysis data of different reservoirs in the field. Owing to the component fractionation caused by geochromatographic effect, the methane and isobutane had priority over the heavy hydrocarbons and mormal butane to migrate respectively; the escaping light hydrocarbon (CH4) was taken by bacteria in the process of compactification of the overlying sandstone cap rocks, thus causing the methane to be gradually diluted in gas composition; and the δ13C1 and δ13C2 in natural gas became heavy along with the decrease in depth. Therefore the differentiation of gas composition in the process of compactification of the overlying caprocks can be traced out by above-mentioned geochemical parameters.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2004年第11期15-18,共4页
Natural Gas Industry
基金
石油天然气集团公司油气地球化学重点实验室项目资助。
关键词
凝析气藏
天然气组分
运移
轻烃
成藏过程
甲烷
气体组分
示踪
盖层
碳同位素
Bacteria
Butane
Diffusion
Ethane
Exploratory geochemistry
Fractionation
Isotopes
Methane
Natural gas fields
Rocks
