建南气田海相天然气藏成因类型探讨  

Genetic Type of Natural Gas of Marine Facies in Jiannan Gas Field

作　　者：王韶华[1] 万云强[2] 林娟华[2] 

机构地区：[1]中国地质大学(武汉)资源学院,湖北武汉430074 [2]江汉油田分公司勘探开发研究院,湖北潜江433124

出　　处：《石油天然气学报》2008年第4期37-42,共6页Journal of Oil and Gas Technology

摘　　要：截止目前为止,建南气田发现嘉一段、飞三段、长兴组及黄龙组4个工业气层,下三叠统、二叠系、下志留统3套气源岩。通过研究不同产气层的气体组分、烷烃碳同位素系列、天然气浓缩轻烃特征认为,不同产层的天然气均为有机成因,属高温裂解气;天然气的甲乙烷碳同位素普遍存在倒转(即δ13C1>δ13C2),主要是由于煤成气和油型气的不同源岩的或不同成熟度的气混合的结果;天然气藏中的混合气以腐泥型的油型气贡献以主,少量腐殖型气,而石炭系天然气成因主体属志留系烃源岩所生油的二次裂解水溶气。There were four gas-bearing strata with commercial value in Jiannan Gas Field, including Jia-1 Member, Fei-3 Member, Changxin Member and Huanglong Member. The gas in these reservoirs sourced from the lower Triassic, Permian and the Lower Silurian. Through studying the component of natural gases and carbonic isotope characteristics of alkanes from different gas-bearing strata and component of light hydrocarbon, it is believed that those natural gases are pyrolysis gases formed under high temperature as organic origin. The carbon isotopes of methane and ethane are generally inversed in Jiannan Gas Field, mainly come from mixture of coal-derived and oil-derived gases in source rocks with different maturities. Mixed gases in natural gas reservoir are mainly contributed to oil-derived gases. Genetic type of natural gas in carbonate mainly belongs to water-dissolved gases of oil-separated gases from Silurian hydrocarbon source rocks.

关 键 词：建南气田 气体组分特征 碳同位素系列 轻烃组成 

分 类 号：P618.13[天文地球—矿床学]