柴达木盆地北缘冷湖七号构造油气成藏过程与模式  

Process and Model of Hydrocarbon Accumulation in the Area of Lenghu No.7 on the Northern Margin of the Qaidam Basin

作　　者：李宏义[1] 汤良杰[1] 姜振学[1] 罗群[2] 

机构地区：[1]中国石油大学盆地与油藏研究中心,北京102249 [2]中国石油大学石油天然气成藏机理教育部重点实验室,北京102249

出　　处：《地质学报》2007年第2期267-272,共6页Acta Geologica Sinica

基　　金：国家自然基金项目(编号40472078);国家"十五"天然气(二期)攻关项目(编号2004BA616A-04)共同资助的成果。

摘　　要：本文在对冷湖七号油气成藏条件综合分析的基础上,依据构造发育史与烃源岩生、排烃史,结合流体包裹体均一温度,分析了冷湖七号构造油气藏形成期次和过程,总结了东、西2个构造高点的油气成藏模式。研究结果表明：①冷七1井N2^1层包裹体主要为含烃盐水包裹体和气态烃有机包裹体,其均一温度明显分为60-70℃和110-130℃两个峰值区,对应地质时间分别为N2^1-N2^2时期和N2末-现今。结合源岩生、排烃史和构造演化史分析表明N2^1-N2^2时期为冷湖七号油气成藏的主要时期;②冷湖七号东高点N2^1气藏形成机理与模式为：断控同生隆起-单源供烃-不整合、断裂输导-浮力驱动-次生型断裂遮挡油气成藏模式;西高点E3油藏形成机理与模式为：同生隆起-双源供烃-不整合、断裂输导-浮力驱动-残留型原生油藏成藏模式。On the basis of synthetic study on the geological conditions in the area of Lenghu No. 7, the course and model of hydrocarbon accumulation were discussed depending on the research of the tectonic evolution and the generation and expulsion history of source rocks and homogenization temperatures of fluid inclusions. The result shows,①Fluid inclusions in N2^1 reservoir can be divided into two types of saltwater inclusion and organic inclusion. Homogenization temperatures of inclusions can be divided into two periods of 60 - 70℃ and 110- 130℃ and their corresponding geological periods are Early Pliocene-Middle Pliocene and the end of Pliocene-Present respectively. A mass of oil and gas injection occurred in the period from the Early Pliocene to Middle Pliocene; ②The hydrocarbon accumulation mechanism and model of western structural high oil pool of Lenghu No. 7 can be summarized as syndepositional upheaval structural trap, two hydrocarbon sources, unconformity and faults as migration channels, buoyancy as dynamic forces, and finally a destructive primary reservoir. While that of the western structural high oil pool of Lenghu No. 7 can be summarized as syndepositional upheaval controlled by fault structural trap, single hydrocarbon source, unconformity and faults as migration channels, buoyancy as dynamic forces, and finally a secondary fault sealed reservoir.

关 键 词：柴达木盆地北缘 冷湖七号 成藏期次 成藏过程 包裹体 均一温度 

分 类 号：P618.13[天文地球—矿床学]