沉积盆地、结晶基底和油、气成因理念与第二深度空间勘探和开发

在石油、天然气的勘探和开发研究中,涉及到深部空间的介质、结构和属性,在沉积建造上涉及到陆相沉积、海相沉积和火山岩相,在油、气成因理论上涉及到有机成因和无机成因,在机制上涉及到深部流体的分异、调整、运移和动力作用.这些本质性问题的研究和探讨是人们十分关注的科学领域.基于油、气生、储和形成的理论、应用和成效的研究提出,有几个基础性的理念问题必须重新认识,特别是沉积建造与古老变质岩结晶基底;双相（海相和陆相）沉积建造与盆地的内涵和双基（有机和无机）混合油、气成因理念.清晰地厘定这些认识不仅有益于对油、气形成、聚集和勘探及开发给出一个更为科学的深部空间,即第二深度空间（5000~10000 m）的油、气勘探,而更为重要的是基于对这些理念的重新认识和深化研究可构建新的思路或理论,且在新的理念导向下,强化油、气深部勘探,以期能在理论研究和实践应用中取得新的成效,发现大型与超大型油、气田.     

第二深度空间(5000～10000 m)油、气成藏和潜力分析

近半个世纪以来,我国的油、气勘探和开发实践主要集中在中、新生代以来的陆相沉积盆地中,即第一深度空间(5000 m).对第二深度空间(5000~10000 m)陆相和海相,即双相沉积建造中的油、气能源未能给予切实关注,仅为在近年来才得以重视和践行.通过对国内外诸多油、气田中的油、气成藏、储存、运移与深层过程的分析和研究发现,我国广泛陆相沉积建造的深处尚分布着丰富的海相沉积建造;且我国古生代的沉积地层确属变质很浅或不变质的层系;以往的油、气形成温度、压力和孔隙度的门限已逐被国内、外油气勘探与开发的实践所突破;第二深度空间的油、气成藏具有很大潜力.以上理念的提出与实施不仅大为扩展了勘查油、气的深部空间,更为重要的是揭示了第二深度空间将必是21世纪上、中叶在深处发现大型、超大型油、气藏的必然轨迹.     

地壳内部第二深度空间(5000～10000m)石油与天然气地球物理勘探:化石能源发展的必由之路

任何国家要快速工业化和经济腾飞均必须依赖于大量能源的供给和消耗,当今中国正处在快速发展之际,现已成为世界上化石能源消耗的第二大国,预测在2012年前后在一次性化石能源消耗中将会超过美国,而成为世界上第一能源消耗大国.面临这种必然的格局,我国必须不失时机地、多元化地利用世界能源,同时又必须坚定的立足于本土,建立起安全、可靠和能保证持续供给的能源战略后备基地.对国内外油、气发展势态的综合研究表明：(1)在中国油气的生、储构造和岩性极为复杂、油田整装性差的条件下,一定要正确、认识和厘定双相（陆相+海相）沉积盆地、古老结晶基底和双基混合成因（有机+无机）的理念,以拓展勘探和开发空间;(2)科学理解中国油、气储量和产量的潜力,强化第二深度空间（5000～10000 m）油、气能源的勘探和开发乃本世纪能源发展的必由之路;(3)加强地球物理勘探高、新科学与技术,即新理论、方法和新技术的研究和应用乃是发现深层大型、超大型油气田和提高油田采收率的根本保证.     

三峡水库坝址及邻区中上地壳P波速度结构

利用三峡地震台网的到时资料,采用地震层析成像技术重建了三峡水库坝址及邻区中上地壳P波三维速度图像,深部构造研究结果是：（1）黄陵背斜岩性均匀完整、固结程度高,高速异常到20km深度依然可见,形状随深度变化．（2）秭归盆地沉积厚度不均匀,最厚处约6km．（3）结晶基底顶面在0～7km、底面在14～16km．（4）黄陵背斜与秭归盆地之间及附近区域和培石附近区域深部存在上地幔部分熔融物质,现今构造发展与演化与上地幔熔融物质冷却固化过程密切相关．（5）九湾溪断裂东西两侧地区地壳深部构造的速度结构不同,是三峡地区重力梯度带成因需要考虑的因素．（6）库水渗透作用对地壳浅层速度结构产生影响．     

松辽盆地北部基底浅变质岩热模拟实验及其气态产物地球化学特征

松辽盆地北部徐深气田探明储量已超过1000×108m3,是中国潜在的一个大气田区.但是,关于深层天然气的成因和来源仍存在较多争议.盆地北部基底浅变质岩分布广泛,是深层天然气的可能气源岩.主要通过对松辽盆地北部基底浅变质岩的热模拟实验,对其生烃潜力及其气态产物地球化学特征进行研究.将取自盆地基底石炭-二叠系浅变质岩在半封闭体系下从300℃加热到550℃进行生烃模拟,温度间隔为50℃,并对每个温度点气态产物进行定量与地球化学分析.实验结果表明:热模拟生成气体烷烃碳同位素组成δ13C1<20‰,δ13C1<δ13C2<δ13C3或δ13C1<δ13C2>δ13C3,表现为高过成熟煤成气的特征;均不具有无机气反序的特征(即δ13C1>δ13C2>δ13C3),与兴城气藏烷烃气碳同位素特征不符,而与取自盆地基底的天然气样碳同位素相近;模拟气体与高过成熟煤成气或油型气混合均不能使烷烃气碳同位素系列反序.浅变质岩具有一定的生烃潜力,相当于烃源岩Ro在2.0%～3.5%范围内,生烃强度为3.0×108～23.8×108m3/km2.     

秦岭造山带与沉积盆地和结晶基底地震波场及动力学响应

秦岭-大别造山带横贯中国大陆中部,并将我国东部分为南北两部;即华北克拉通和扬子克拉通.在南、北相向运动力系驱动下构成了一个极为复杂的复合、叠加构造带、成矿带和地震活动带.同时导致了该地域异常变化的沉积建造和强烈起伏的结晶基底.然而对它们形成的地球物理边界场响应,岩相和结构的异常变化尚不清晰,特别对盆山之间的耦合响应更缺乏深层动力过程的理解.为此本文通过该区榆林-铜川-涪陵长1000 km剖面的地震探测和研究结果提出：（1）沉积建造厚度变化为4~10 km,结晶基底起伏强烈,幅度可达4~6 km;（2）一系列基底断裂将该区切割为南鄂尔多斯盆地和秦岭北缘前陆盆地、秦岭-大巴造山带和南缘前陆盆地与东北四川盆地,其中前陆盆地为秦岭北渭河盆地和秦岭南通江-万源盆地;（3）秦岭造山带是北部华北克拉通向南推挤、南部扬子克拉通向北推挤下隆升的陆内山体,并构筑了其南、北前陆盆地;（4）秦岭造山带的南、北边界并非是一条边界断层,而应是包括前陆盆地在内的组合界带;（5）秦岭与大巴弧形山系源于同一深部结晶基底,即同根生.这一系列的新认识对深化理解秦岭-大巴造山带形成的深层动力过程和演化机理及厘定扬子克拉通的真实北界具有极为重要的意义.     

攀枝花古地幔柱壳、幔结构与地球物理边界场特征

攀枝花古地幔柱的形成与演化对这一地域的大地构造格局、金属矿产的聚集和区域大陆动力学研究均有着极为重要的科学意义和应用价值.本文通过穿越攀枝花古地幔柱中心部位的四条人工源深部地震探测剖面和区域地球物理边界场响应研究提出：（1）攀枝花古地幔柱具有特异的壳、幔速度结构;（2）在其中心部位由结晶基底到壳、幔边界均为高速体,且结晶基底和Moho界面局部隆起、地壳内部存在厚达10余千米的低速层,且被数条深、大断裂切割;（3）重力场、磁力场的边界异常场响应组构了攀枝花古地幔柱的地表形态和中心部位的圈闭范围.     

鄂尔多斯盆地典型地区放射性异常特征及其地质意义

长期以来,鄂尔多斯盆地油、气、煤、铀(浅部)作为单一矿产研究成果虽多,但对其共存特征和共生成藏机制研究较少,也缺乏对盆地深部铀富集特征研究.而对多种能源矿产同盆共存关系、共生规律深入研究,将会促进盆地重要矿产综合预测和协同开发.以大量的地球物理测井资料、地质资料为基础,从该区的高伽马异常入手,研究伽马异常展布特征.通过对所取33件岩心样进行放射性元素含量测试分析,结果表明在本区自然伽马异常增高是由于铀元素增加而引起,而铀元素的富集主要是由于盆地中铀的活化和聚集引起.在对放射性异常认识的基础上,通过鄂尔多斯盆地内油、气、煤、铀4种矿产同盆共存的现实以及成藏(矿)机理研究表明,盆地内放射性铀与油、气、煤的成藏(矿)具有一定的相互促进作用,为多种能源协同勘探提供了重要的理论依据.     

柴达木盆地涩北生物气藏充注-散失过程及其富集规律研究

柴达木盆地东部涩北气田是我国发现的最大生物气田,为了揭示其充注-散失过程与生物气富集规律,利用不同深度生物气组成和稳定碳同位素分馏现象,结合成藏地质模式分析,用扩散模型计算了其成藏以来的生物气散失量,并与现存储量相加得到充注量.涩北生物气田为多储盖组合叠置的背斜气田,其深部储层为气源直接充注、浅部储层接收下伏气层扩散来的生物气为间接充注.提出的某一储层相对散失量(散失量与充注量的比值)可以表征生物气富集程度,当相对散失量<0.6,有利于生物气富集并形成高效气藏,相对散失量>0.6则不利于生物气聚集、或者形成低效气藏.     

中国沉积盆地大中型气田分布与天然气成因

中国沉积盆地丰富的天然气资源是由我国独特的地质环境决定了的.古生界海相高演化程度的烃源岩、广泛分布的煤系地层以及第四系低温盐湖相地层等,都决定了中国境内天然气的资源前景相当广阔.迄今已在东部、中部、西部及海域的大多数含油气盆地,从前寒武系、古生界、中生界至新生界几乎所有的地质时期,都发现了大规模的天然气聚集.这些大中型天然气藏主要以烃类气体为主,干燥系数大,非烃含量少,碳同位素值分布范围宽,成因多种多样,几乎包括了所有成因类型的天然气,如煤成气、油型气、生物气和无机气等.其中煤成气在天然气资源中占主导地位,特别是已探明的几个千亿方的大型气田,如克拉2、苏里格、大牛地等,均属于煤成气或以煤成气为主;油型气在我国海相盆地占有重要地位,如四川盆地海相天然气田,主要是由原油裂解形成的;在柴达木盆地和松辽盆地西斜坡,分别发现了原生型的生物气大气田和稠油降解成因的次生生物气;无机成因气主要分布在中国东部,尤其是近年来在松辽盆地发现的较大规模的CO2和烃类气体的聚集,意味着无机成因气在中国东部将有很大的勘探潜力.     

重论"上生下储"与"侧向运移"

油气运移是油气藏形成与分布研究的基础．随着生油层理论的建立和发展,油气“上生下储”与“侧向运移”已经成为解释生油层与储集层关系的金科玉律．随着世界范围内油气勘探实践的积累和油气形成与分布研究,特别是对基岩油气藏勘探研究的不断深入,上述运移途径需要重新加以认识。     

The formation mechanism of high-quality dolomite reservoir in the deep of Puguang Gas Field

The discovery of Puguang Gas Field provides the exploration of China deep marine carbonate rock with important references.In Puguang Gas Field,the dolomite reservoirs discovered in the deep are the best in the present of China,which present big thickness and wide-range distribution,and develop abundant secondary porosity.The researches show that Puguang Gas Field bears the characteristics of early gas-filling time,deep burial,high matured organic matter and long-term interaction of hydrocarbon(oil and gas)-water-rock(carbonate reservoir).The developments of secondary pores in this area are affected by multiple diagenesis and their formation mechanisms are complicated.Through the research on depositional environment,sedimentary facies and reservoir porosity characters of Changxing and Feixianguan Formations,it is thought that high-quality dolomite reservoirs of Puguang Gas Field form on the favorable sedimentary facies belts,which are the integrate result affected by several factors including superficial corrosion,burial corrosion,overpressure and tectonic movement,among which burial corrosion of TSR to reservoir and overpressure formed by thermal evolution of organic matter have great effect on the formation of secondary porosity of Changxing and Feixianguan Formations.     

南黄海盆地中部隆起CSDP-2井初步成果及其地质意义

南黄海盆地是新生代、中生代、古生代大型叠合盆地,具有良好的油气资源前景.中部隆起是南黄海盆地的二级构造单元,由于缺乏钻探资料,对中部隆起前新生代地层分布和油气资源前景的认识众说纷纭.因此,在中部隆起上实施科学钻探,探查中-古生代地层属性,对研究南黄海区域地质构造特征和油气地质条件意义重大.针对科学钻探目标,采用区域地质背景指导下的地质、地球物理综合研究的方法,拟定了科学钻探井(CSDP-2井)位置;利用叠前时间偏移成像处理剖面,采用地震相、地震速度分析和储层预测技术,进行了钻前层位预测和油气储层分析.该井由青岛海洋地质研究所负责的"大陆架科学钻探"项目实施,全取芯钻探成果表明,中部隆起上赋存了三叠系-奥陶系海相残余地层,发育中等—好级别的、厚度较大的海相中-古生界烃源岩,在三叠系青龙组、二叠系龙潭组和栖霞组、泥盆系和志留系中获得多层不同级别的油气显示.CSDP-2井的钻探发现,结束了关于中部隆起海相地层属性的争论,坚定了南黄海海相油气勘探的信心,为区域地质研究和油气地质条件分析提供了基础数据.     

Natural gas origins of large and medium-scale gas fields in China sedimentary basins

China sedimentary basins present abundant natural gas resource thanks to its unique geological settings.Marine highly-matured hydrocarbon source rocks,widespread coal-measure strata and low temperature Quaternary saline strata,etc.,indicate the wide foreground of China natural gas resources. Up to now,most of the petroliferous basins have been discovered to have wholesale natural gas accumulation from Precambrian,Paleozoic,Mesozoic to Cenozoic in the east,the central,the west and the coast of China.These large and medium-scale gas reservoirs are mainly composed of hydrocarbon gas with big dry coefficient,tiny non-hydrocarbon,wide carbon isotope distribution and varying origin types,the hydrocarbon gas includes coal-formed gas,oil-formed gas,biogenic gas and inorganic gas, etc.Coal-formed gas is the main type of China natural gas resources,in particular several explored large-scale gas fields(>100 billion cubic meter)of Kela 2,Sulige and Daniudi,etc.,they all belong to coal-formed gas fields or the gas fields consisting mostly of coal-formed gas.Oil-formed gas is also abundant in China marine basins,for example marine natural gas of Sichuan Basin generated from crude oil cracking gas.Primary and secondary biogenic gas fields were discovered respectively in the Qaidam Basin and Western Slope of Songliao Basin.In addition,inorganic gases are mainly distributed in the eastern China,in particular the Songliao Basin with abundant carbon dioxide accumulation,indicating that the eastern China present large exploration potential of inorganic gas.     

中国近海前新生代残留盆地初探

中国近海沉积盆地按形成时代可以划分为新生代盆地和前新生代盆地。新生代陆相碎屑岩断陷盆地有良好的油气前景,而古生代还有广泛海相碳酸盐岩分布地区,只要它们经受中生代挤压,改造后还能保留下来,就具有巨大的油气潜力。初步分析中国近海的油气勘探资料及大地构造演化史表明,陆内断坳盆地下伏以古生代碳酸盐岩为主的残留盆地。而陆缘盆地并不是寻找古生代残留盆地的场所。但在台西南盆地,珠江口盆地潮汕坳陷发育海相中生代盆     

The formation mechanism of high-quality dolomite reservoir in the deep of Puguang Gas Field

The discovery of Puguang Gas Field provides the exploration of China deep marine carbonate rock with important references. In Puguang Gas Field, the dolomite reservoirs discovered in the deep are the best in the present of China, which present big thickness and wide-range distribution, and develop abundant secondary porosity. The researches show that Puguang Gas Field bears the characteristics of early gas-filling time, deep burial, high matured organic matter and long-term interaction of hydrocarbon (oil and gas)-water-rock (carbonate reservoir). The developments of secondary pores in this area are affected by multiple diagenesis and their formation mechanisms are complicated. Through the research on depositional environment, sedimentary facies and reservoir porosity characters of Changxing and Feixianguan Formations, it is thought that high-quality dolomite reservoirs of Puguang Gas Field form on the favorable sedimentary facies belts, which are the integrate result affected by several factors including superficial corrosion, burial corrosion, overpressure and tectonic movement, among which burial corrosion of TSR to reservoir and overpressure formed by thermal evolution of organic matter have great effect on the formation of secondary porosity of Changxing and Feixianguan Formations.     

The scientific connotation of oil and gas formations under deep fluids and organic-inorganic interaction

As a relatively stable craton block in the earth system, the petroliferous basin is influenced by the evolution of the earth system from the early development environment of source rocks, hydrocarbon formation, and reservoir dissolution to hydrocarbon accumulation or destruction. As a link between the internal and external factors of the basin, deep fluids run through the whole process of hydrocarbon formation and accumulation through organic-inorganic interaction. The nutrients carried by deep fluids promote the bloom of hydrocarbon-generating organisms and extra addition of carbon and hydrogen source, which are beneficial to the development of high-quality source rock and enhancement of the hydrocarbon generation potential. The energy carried by the deep fluid promotes the early maturation of the source rock and facilitates the hydrocarbon generation by activation and hydrogenation in high-mature hydrocarbon sources. The dissolution alteration of carbonate rocks and clastic reservoirs by CO_2-rich deep fluids improves the deep reservoir space, thus extending the oil and gas reservoir space into greater depth. The extraction of deeply retained crude oil by deep supercritical CO_2 and the displacement of CH_4 in shale have both improved the hydrocarbon fluidity in deep and tight reservoirs. Simultaneously, the energy and material carried by deep fluids(C, H, and catalytic substances) not only induce inorganic CH_4 formation by Fischer-Tropsch(F-T) synthesis and "hydrothermal petroleum" generation from organic matter by thermal activity but also cause the hydrothermal alteration of crude oil from organic sources. Therefore, from the perspective of the interaction of the earth's sphere, deep fluids not only input a significant amount of exogenous C and H into sedimentary basins but also improve the reservoir space for oil and gas, as well as their enrichment and accumulation efficiencies.