“源热共控”中国近海盆地油气田“内油外气”有序分布  

Regular Distribution of Inside-oil Fields and Outside-gas Fields Controlled by Source Rocks and Heat in China Offshore Basins

作　　者：张功成[1] 陈国俊[2] 张厚和[1] 李友川[1] 梁建设[1] 杨树春[1] 

机构地区：[1]中国海洋石油研究总院,北京100027 [2]中国科学院油气资源研究重点实验室,兰州730000

出　　处：《沉积学报》2012年第1期1-19,共19页Acta Sedimentologica Sinica

基　　金：国家973项目(2009CB219400);国家科技重大专项(2008ZX05025;2011ZX05025);国土资源部全国油气资源战略选区调查与评价项目(XQ-2007-05)联合资助

摘　　要：源热共控油气形成,烃源岩是油气形成的内因,热是油气形成的外因,内因和外因缺一不可,二者耦合作用控制了含油气区内油气的形成、资源潜力与分布模式。中国近海沉积盆地主要属于新生代伸展盆地或张扭盆地,古近纪发生裂陷,早—中中新世发生区域性热沉降,晚中新世以来新构造活动在多数盆地比较活跃。中国近海新生代盆地烃源岩主要形成于古近纪裂陷期断陷,根据沉积充填特征分为陆相断陷和叠合断陷,陆相断陷指断陷期地层完全为陆相地层充填的凹陷,叠合断陷指除陆相地层充填外,还存在海相或海陆过渡相地层充填的断陷。渤海海域、黄海海域、珠江口盆地北部坳陷带和北部湾盆地古近纪断陷都属于陆相断陷,处于克拉通内部或大陆架,称为内带;东海盆地、台西盆地、台西南盆地、珠江口盆地南部坳陷带、琼东南盆地及莺歌海盆地的古近纪断陷都属于叠合断陷,处在活动大陆边缘或被动大陆边缘陆坡区,称为外带。内带陆相断陷主要烃源岩为中深湖相源岩,分布时代包括古新世、始新世和渐新世,以始新世为主;外带叠合断陷烃源岩包括湖相烃源岩、海陆过渡相烃源岩和海相烃源岩,其中以海陆过渡相烃源岩为主,分布时代包括古新世、始新世、渐新世,以始新世—渐新世为主。内带湖相烃源岩倾向生油,外带海陆过渡相和海相烃源岩倾向生气。近海盆地内带热流值低—较高,外带热流值高—超高。烃源岩与热场耦合,内带倾油型烃源岩在相对较低的温度场作用下主要生油,外带倾气型烃源岩在较高的温度场作用下主要生气。因此,近海内带主要生油是找油的领域,外带主要生气是找天然气领域。中国近海石油的主要勘探领域在内带的渤海、南海北部北带和南黄海海域断陷,天然气主要勘探领域在外带的南海北部陆坡及东海海域。The hydrocarbone genernation is controlled by the source rocks and the heat.The source rock is the essential factor of the hydrocarbone formation and the heat is the subsidiary.The both are necessary factors.The interactional factors result in the hydrocarbon generation and distribution pattern.In China offshore,the sedimentary basins are of the stretch or extend-slip depressions which formed in Tertiary.The syn-rift occurred in Paleogene.The thermal subsidence formed sequently in the early-middle Miocene.From late Miocene,the Neo-tectonic movement happened actively in a great number of basins.The source rocks formed mainly during the period of the paleogene syn-rifting.According to the characters of the sediments,the basins are divided into two groups,namely,the continental/terrestrial rift and the superimposed rift.The continental rift are the sags that the syn-rifting stratum are absolutely composed of the terrestrial sediments.The superimposed rift are the sags filled with the marine sediments or the onshore-offshore sediments besides the terrestrial sediments.Bohai bay basin,Yellow Sea Basin,the northern of the pearl mouth basin and Beibuwan Basin are parts of the continental rifts.Those basins,located in the inner of the craton or the continental shelf,are assigned into the inside belt.The outside belt,consisted of the East China Sea Basin,Taixi basin,Taixinan basin and the southern of the pearl mouth basin,is situated in the active continental margin or the continental slope which is subjected to the passive continental margin.In the inside belt,the main source rocks are the middle-deep lake facies mud which formed in the Paleocene,the Eocene and the Oligocene.The Eocene source rocks are dominated.In the outside belt,the source rocks are composed of the lake facies,the onshore-offshore facies and the marine facies sediments and the onshore-offshore facies is the main source rocks.The geologic age of the source rocks is similar with that of the inside belt but the Eocene-Oligocene is dominated.The source ro

关 键 词：烃源岩 热流 油气田分布 有序性 源热共控论 

分 类 号：TE121.1[石油与天然气工程—油气勘探]