辽河坳陷东部凹陷天然气特征及成因类型  

Characteristics and genetic types of natural gas in the eastern sag of the Liaohe Depression

作　　者：李军[1,2] 侯读杰[3] 李敬含[2] 张金川[3] 刘鑫[2] 徐波[3] 

机构地区：[1]中国石油勘探开发研究院 [2]中国石油辽河油田公司勘探开发研究院 [3]中国地质大学(北京)能源学院海相储层演化与油气富集机理教育部重点实验室

出　　处：《天然气工业》2011年第2期43-47,124,共5页Natural Gas Industry

基　　金：国家自然科学基金(编号:40972097;40672087)

摘　　要：辽河坳陷东部凹陷是辽河油田重要的天然气生产区,随着勘探程度的不断深入,亟待从整体格局上对天然气成因、成藏与分布规律进行系统研究,确定下一步勘探方向与勘探潜力。为此,依据该区天然气的地球化学特征(含氮特征、干燥系数、碳同位素特征、甲烷氢同位素特征、轻烃特征等),对其成因类型和分布规律进行了分析。结果认为:该区天然气具有较明显的混源特征,既表现为不同热演化程度天然气的混合,也表现为不同成因类型天然气的混合;不同层系、不同地区天然气混合比例有着较大区别,总体上以生物—油型混合气和油型—煤型混合气为主;按照成熟阶段来划分则以热解气为主,裂解气和过渡带气各占3%和6%。The eastern sag of the Liaohe Depression is one of the major gas production zones in the Liaohe Oilfield.Along with the deepening degree of exploration,it is urgent to systematically study the genesis,accumulation and distribution of gas,so as to evaluate gas potentials and identify future exploration targets.The genetic types and distribution patterns of gas are defined through analyzing the geochemical features of gas,such as nitrogen content,dry coefficient,carbon isotopic characteristics,hydrogen isotopic characteristics of methane,and light hydrocarbon features.The natural gases in the study area are obviously of mixed origins.There are both source-mixed gases of different thermal evolution stages and mixed gases of different genetic types.The composition of mixed gases varies greatly in different layers and in different areas.Biogenetic-terrigenous-dominated petroliferous mixed gas and terrigenous-dominated coal-related mixed gases are predominant as a whole.As to maturation stages,gas from thermal degradation is predominant,while pyrolysis gas and transition gas are much less,accounting for 3% and 6% respectively.

关 键 词：辽河坳陷 东部凹陷 天然气 成因类型 混源气 碳同位素 有机质类型 热演化 混合比例 

分 类 号：P618.13[天文地球—矿床学]