中国大陆构造强烈活动性对海相盆地油气成藏和勘探的影响

中国大陆频繁而又强烈的构造活动,既有对古老海相含油气盆地进行强烈改造导致油气大量散失并使油气藏分布复杂化而增加勘探难度这不利的一面,又有形成多旋回沉积建造和多期含油气盆地发育这有利的一面。在古生代海相盆地发育过程中,挤压抬升作用使古隆起顶部地层遭受侵蚀,造成早期聚集油气的大量散失,而古陆块活动性大,地壳变形强烈,多期沉降的陆缘坳陷和陆内坳陷又有利于优质烃源岩堆积。挤压抬升所形成的古隆起伴生有溶蚀孔洞和构造裂缝,可以改善储层物性,使古隆起成为晚期生成油气的有利聚集场所。中一新生代,中国大陆受到相邻板块的强烈作用,古老的海相盆地受到强烈改造和破坏,缩小了海相地层的有利勘探范围;中—新生代构造和盆地叠加作用,则使古生界变形强烈、埋藏深度加大并且造成复杂的地貌,增加了海相油气藏的勘探难度。但同时,中—新生代地层的覆盖也是海相地层深埋生烃和古油藏保存的必要条件,在海相油气封盖层未受到严重破坏的地区,具有良好的油气勘探前景。     

济阳坳陷中-新生代叠合盆地及油气成藏

济阳坳陷中-新生代盆地是多次构造与沉积叠加形成的叠合盆地.通过分析不同走向断裂的活动特征,明确了中-新生代控盆断层经历了印支构造运动晚期北西(西)向逆冲断层、燕山构造运动中晚期北西(西)向断层构造反转、燕山-喜马拉雅构造运动过渡期北西(西)向断层的消亡及北东(东)向断层的产生3次重要的发育及转型阶段.将济阳坳陷中-新生代叠合盆地划分出"中凹新凹"、"中凹新凸"、"中凸新凹"、"中凸新凸"4种类型的叠合单元,探讨了叠合盆地中断层叠合、界面叠合以及构造叠合对油气成藏的作用,建立了中生界油气成藏模式,指出了"中凸新凹"型叠合单元与"中凹新凸"型叠合单元是中生界最为有利的成藏场所.     

江汉盆地构造特征与油气勘探

江汉盆地位于中扬子区。本文所定义的范围是,北界为襄樊-广济断裂,西界为黄陵隆起,南界为江南隆起,东界为团城-麻风断裂,面积约5.5km2。     

中国西部叠合盆地油气多期成藏模式及勘探有效性

我国西部叠合盆地油气资源丰富,随着勘探难度逐年增加,如何准确定位有利成藏区带对增加勘探成功率至关重要。通过对比叠合盆地主要大中型油气田发现,叠合盆地大都为多期成藏,且晚期成藏有利于油气规模化保存。在大量总结叠合盆地多个油气成藏过程、特点和模式的基础上,结合研究区带的构造演化特点,按照叠合盆地构造变动模式划分,将西部叠合盆地油气多期成藏模式划分为5种,分别是油气连续充注型、早期强烈改造型、中期强烈改造型、晚期强烈改造型和多期充注改造交替型。在晚期成藏有利于油气勘探的前提下,分析认为具有油气连续充注型油气成藏的区域和周边地区由于构造变动轻微,破坏幅度最小,因此油气藏类型较多,规模化可能性最大,最具油气勘探有效性,而多期充注改造交替型成藏模式在构造变动频繁剧烈的影响下,使得油气藏破坏量较大,保存下来的可能性很小,因此也最不具备勘探有效性,此类地区应该尽可能规避。     

苏北盆地浅层油气成藏特征与勘探前景

苏北盆地浅层 (上第三系 )油气显示极为活跃 ,近年来 ,通过油气遥感、浅层地震、化探、钻井等综合勘探、研究 ,探讨了浅层油气的成藏特征和控制因素 ,评价出苏北盆地浅层油气勘探的 6个浅层含油气区带。其中 ,许庄、江都—吴堡地区和泰兴—海安地区属于有利区带 ,也是近期浅层油气勘探的主要试验勘探区带 ,提交苏北盆地第一口以寻找浅层油气为主的探井———XQ1井。 2 0 0 3年 3月 ,该井发生了江苏油田有史以来的强烈井喷。浅层油气的成藏 ,具有多来源的油气 ,储层物性好、盖层条件理想 ,为油气的成藏形成良好的储盖组合。气藏类型以岩性圈闭和低幅度构造圈闭为主 ,油气层埋藏深度一般为 5 0 0m～ 1 0 0 0m ,一般为 80 0m左右。初步预测苏北盆地浅层油气资源量可达 397 4 4× 1 0 8m3 ～ 1 4 1 8 5 5× 1 0 8m3 ,其中 ,江都—吴堡区带的资源量为 1 77 5 4× 1 0 8m3 ～ 5 0 3 0 4× 1 0 8m3 ;泰兴—海安区带的资源量为 1 30 6 0× 1 0 8m3 ～ 6 0 4 6 1× 1 0 8m3 。     

复合叠合盆地油气成藏特征——以塔里木盆地为例

复合叠合盆地的多旋回演化会形成多个油气系统。每个油气系统中的成藏作用各具特点 ,其共同点是 :烃源和封盖这两个要素是首要前提 ,二者控制着烃类的资源总量、充满度、系统的类型和性质 ,在这两个前提下 ,储层、圈闭、通道等则控制着油气藏的规模、丰度 ;成藏的温压环境则影响着烃类流体性质。塔里木盆地是典型的复合叠合盆地 ,共有 9个油气系统 ,可分为前陆区的腐殖型和克拉通区的腐泥型两类。前者为单旋回富气区 ,有 3种成藏机制 ;后者为多旋回富油区 ,具有 4个成藏期。多种类型的油气系统、多样的成藏机制和多期的成藏作用是复合叠合盆地油气成藏的重要特征     

四川含油气叠合盆地基本特征

随着近年来四川盆地油气勘探的不断突破,重新审视其基本地质特征和油气成藏特点变得迫切而必要。四川盆地是典型的叠合盆地,显生宙以来经历了震旦纪—中三叠世伸展体制下的差异升降和被动大陆边缘（海相碳酸盐岩台地）、晚三叠世—始新世挤压体制下的褶皱冲断和复合前陆盆地（陆相碎屑岩盆地）、渐新世以来的褶皱隆升改造（构造盆地）3大演化阶段以及晚三叠世（被动大陆边缘→前陆盆地、海相碳酸盐岩—海相碎屑岩、海相碎屑岩→陆相碎屑岩）、晚白垩世（前陆盆地沉降中心的迁移、秦岭构造域→青藏构造域、沉积→部分隆升剥蚀）、始新世（外流盆地→内流盆地、沉积盆地→地貌盆地、沉积→整体隆升剥蚀）3大关键构造变革/沉积转换期。印支期以来,四川盆地受周边多个方向造山带（北缘秦岭造山带、东缘雪峰陆内构造系统、西南缘青藏高原）多期活动影响,形成多组、多期构造的复合—联合叠加。现今盆山构造格局呈现明显的三分性（地貌、基底和构造形迹）,发育突变型和渐变型两类盆山边界。按盆地不同区域盆山结构特征、定型时间和主控因素,可将四川盆地划分为5大盆山结构区： Ⅰ区： 川北突变型盆山结构区（秦岭构造控制域）; Ⅱ区： 川西突变型盆山结构区（青藏构造控制域）; Ⅲ区： 川东渐变型盆山结构区（雪峰构造控制域）; Ⅳ区： 川西南渐变型盆山结构区（青藏—雪峰—基底构造联合控制域）和Ⅴ区： 川中原地隆起—盆地区（基底构造控制域）。四川盆地是我国西部重要的含油富气盆地,勘探潜力巨大。这是由充足的烃源和良好的保存条件所决定的。首先,多阶段盆地叠合演化造就了5套重要的烃源层,总厚度可达1500～2500 m,有机碳含量高,生烃量大,成气率高。其次,中下三叠统膏盐岩的发育对海相油气起了重要的封闭作用,而冲断带—前陆盆地二元结构和隆升剥蚀作用较弱的特点大大增强了突变型盆山结构区的保存条件。此外,晚白垩世以来的隆升作用使古气藏（储气中心）发生调整或破坏的同时,也为现今气藏（保气中心）的形成创造了条件,隆升作用还造成流体跨层流动和天然气爆发式成藏。叠合盆地演化的多阶段性、多组多期构造的复合—联合作用、储层的非均质性和天然气的活动性决定了四川盆地油气勘探的复杂性、长期性和曲折性,同时说明不能用单一的勘探思路、勘探方法和成藏理论来指导整个盆地的油气勘探,即勘探策略也应多样化。     

我国叠合盆地油气调查战略思考

20世纪我国油气勘探在中、新生代陆相裂谷及前陆盆地中获得油气主要储量,21世纪我国远景储量增长将向古生代克拉通盆地海相碳酸盐岩转移,塔河大油田、苏里格大气田、普光大气田等大型油气田的发现,预示着我国陆上前中生代海相碳酸盐岩具有良好的勘探前景,是我国油气资源战略接替的重要领域。但由于我国含油气盆地绝大多数盆地具有叠合盆地性质,勘探特殊,导致油气增长缓慢。从目前油气勘探程度来看,油气工作朝着两个方向发展,一是寻找油气勘探新区、新领域、新层系、新类型,二是加快主要油气盆地新区油气资源勘探前景评价。这不仅需要高新探测技术的支撑,更重要的是要从观念认识上更新,运用新理论新思想突破对叠合盆地深层油气资源赋存状态的复杂地质构造的规律性认识,从战略高度指导油气勘查和评价工作。盆地分析－油气系统－成藏区带－远景评价构成认识和预测叠合盆地新区和成藏潜力评价的主旋律,而“盆地的完整性、改造的微弱性、封闭条件的完好性”则是叠合盆地油气新区初步评价、战略选区的目标所在。      

中国陆上主要含油气盆地石油地质基本特征

中国大陆是由若干大小不等的克拉通与不同时代的造山带组成的拼合体,在显生宙经历了古生代陆洋分化对立阶段,石炭纪－二叠纪软碰撞转化阶段和中,新生代贫山对峙发展阶段,从而形成了陆上３类叠合型盆地;即克拉通与前陆叠合,断坳叠合及残留与新生盆地的叠合     

中国叠合盆地的特点

<正> 叠合盆地,是指经历了多期沟造变革、由多个单型盆地经多方位叠加复合而形成的具有复杂结构的盆地。我国内陆大型含油气盆地基本上都属于叠合盆地,其形成和发展演化受控于中国区域大地构造的发展,具有多旋回性。由于经历多期构造运动的改造,其原型盆地性质往往发生变化,一般又称为残留盆地、改造型盆地或叠合—复合盆地。多期构造演化特征往住表现为早古生代海相碳酸盐岩沉积盆地,晚古生代海陆交互相(含煤)盆地,中—新生代陆相盆地,呈现多方位叠置,具有明显的旋回性和阶段性,在不     

叠合盆地构造变动破坏烃量研究方法探讨

叠合盆地内源岩生成的烃量在运聚过程中只有1％－10％左右的油1‰-10‰左右的气能够富集成有工业价值的油气资源。除源岩残留、储层内滞留、区域盖层形成前排失、地下水喾解和扩散外，构造变动是造成烃类损耗和破坏的重要原因；探讨构造戏量的研究方法对于油气资源评价具有重要意义。研究表明，构造变动破坏烃量主要有三种形式：剥离区域盖层、切断区域盖层的连续性和破坏圈闭的有效容积。构造变动破坏烃量随构造变动强度（剥区或盖层的面积、错断区域盖的距离和破坏圈闭的有效容积百分）增加、构造变动前研究区有效运移烃量以及构造变动过程中区域盖脆性增强而增大。本文探讨了构造破坏烃量的研究方法，建立了构造变动破坏烃量与上列三因素的定量关系模式，并将其成功地应用于塔里木分地。     

Multiple-Element Matching Reservoir Formation and Quantitative Prediction of Favorable Areas in Superimposed Basins

<正>Superimposed basins in West China have experienced multi-stage tectonic events and multicycle hydrocarbon reservoir formation,and complex hydrocarbon reservoirs have been discovered widely in basins of this kind.Most of the complex hydrocarbon reservoirs are characterized by relocation,scale re-construction,component variation and phase state transformation,and their distributions are very difficult to predict.Research shows that regional caprock(C),high-quality sedimentary facies(Deposits,D),paleohighs(Mountain,M) and source rock(S) are four geologic elements contributing to complex hydrocarbon reservoir formation and distribution of western superimposed basins.Longitudinal sequential combinations of the four elements control the strata of hydrocarbon reservoir formation,and planar superimpositions and combinations control the range of hydrocarbon reservoir and their simultaneous joint effects in geohistory determine the time of hydrocarbon reservoir formation.Multiple-element matching reservoir formation presents a basic mode of reservoir formation in superimposed basins,and we recommend it is expressed as T-CDMS. Based on the multiple-element matching reservoir formation mode,a comprehensive reservoir formation index(Tcdms) is developed in this paper to characterize reservoir formation conditions, and a method is presented to predict reservoir formation range and probability of occurrence in superimposed basins.Through application of new theory,methods and technology,the favorable reservoir formation range and probability of occurrence in the Ordovician target zone in Tarim Basin in four different reservoir formation periods are predicted.Results show that central Tarim,Yinmaili and Lunnan are the three most favorable regions where Ordovician oil and gas fields may have formed.The coincidence of prediction results with currently discovered hydrocarbon reservoirs reaches 97%.This reflects the effectiveness and reliability of the new theory,methods and technology.     

Alteration and Reformation of Hydrocarbon Reservoirs and Prediction of Remaining Potential Resources in Superimposed Basins

<正>Complex hydrocarbon reservoirs developed widely in the superimposed basins of China formed from multiple structural alterations,reformation and destruction of hydrocarbon reservoirs formed at early stages.They are characterized currently by trap adjustment,component variation, phase conversion,and scale reformation.This is significant for guiding current hydrocarbon exploration by revealing evolution mechanisms after hydrocarbon reservoir formation and for predicting remaining potential resources.Based on the analysis of a number of complex hydrocarbon reservoirs,there are four geologic features controlling the degree of destruction of hydrocarbon reservoirs formed at early stages:tectonic event intensity,frequency,time and caprock sealing for oil and gas during tectonic evolution.Research shows that the larger the tectonic event intensity,the more frequent the tectonic event,the later the last tectonic event,the weaker the caprock sealing for oil and gas,and the greater the volume of destroyed hydrocarbons in the early stages.Based on research on the main controlling factors of hydrocarbon reservoir destruction mechanisms,a geological model of tectonic superimposition and a mathematical model evaluating potential remaining complex hydrocarbon reservoirs have been established.The predication method and technical procedures were applied in the Tazhong area of Tarim Basin,where four stages of hydrocarbon accumulation and three stages of hydrocarbon alteration occurred.Geohistorical hydrocarbon accumulation reached 3.184 billion tons,of which 1.271 billion tons were destroyed.The total volume of remaining resources available for exploration is～1.9 billion tons.     

Orderliness of Hydrocarbon Accumulation Distribution in Rift Basins of Eastern China

The Cenozoic rift basins in eastern China show a clear temporal and spatial zonation and episodic tectonic evolution, which control their episodic hydrocarbon generation and zonal accumulation. In this paper, based on the study of depositional architecture, hydrocarbon migration system and dynamic evolution in the rift basins, combinations of hydrocarbon accumulation elements were analyzed using sequence stratigraphy. Hydrocarbon distribution in system tracts with different sequence orders was further studied. And we summarized stacking patterns and horizontal combination relationships for different types of reservoirs, such as lithological, tectonic-lithological, tectonic and stratigraphical reservoirs which can be observed from depression center to basin margin. The result reveals that various scales of pools exhibit significant distribution and evolution orderliness in different pool-forming units, i.e., depositional systems, plays and depressions. The regular distribution of various scales of pools is closely related to tectonic evolution and depositional filling in the rift basins. The result can be applied to the fine petroleum exploration in rift basins in eastern China. It will promote the scientific prediction and evaluation of reservoir types and their spatial distribution, lead to the active shifts of exploration targets in different zones, and thus support the stable progress of fine exploration in mature exploration areas.     

沉积盆地深部流体活动及油气成藏效应

沉积盆地深部流体包括幔源深部流体和壳源岩浆等,它们对成矿和油气成藏具有广泛而明显的影响。深部流体的油气成藏效应主要表现在四个方面:(1)形成与深部流体活动有关的无机成因气藏;(2)通过物质和能量交换,参与烃源岩的干酪根热解生烃;(3)通过溶蚀或交代,改变储层的岩石成分或孔渗结构进而改善其储集性能;(4)通过增温,驱动油气快速运移。论述了沉积盆地深部流体对油气成藏效应的研究进展及对油气勘探的重要意义。     

裂陷盆地中的构造变换带及其石油地质意义

构造变换带是裂陷盆地中的重要构造变形。讨论了构造变换带的含义、类型及对油气聚集的意义。裂陷盆地主干正断层之间的几何关系可以分为同向倾斜、背向倾斜和相向倾斜共3种组合方式;正断层之间的构造变换方式可以分为缓冲式、接力式、消长式、传递式和消减式等5种形式,构成15种类型的构造变换带。不同方式的断裂组合所形成的不同构造变换带类型会随着主干正断层位移的渐进增大发生相应的转变。构造变换带是有利的油气聚集区带:(1)它常常是主边界断裂带上地形高差变化较小的部位,是主要碎屑物源注入裂陷盆地的入口处,有利于发育储集层;(2)长期处于盆地内部相对高的构造部位,而且近邻生油凹陷,是油气运移指向区带;(3)它是裂陷盆地构造变形相对复杂的区带,有利于发育多种样式的油气圈闭。     

Oil and Gas Accumulation in the Foreland Basins, Central and Western China

<正>Foreland basin represents one of the most important hydrocarbon habitats in central and western China.To distinguish these foreland basins regionally,and according to the need of petroleum exploration and favorable exploration areas,the foreland basins in central and western China can be divided into three structural types:superimposed,retrogressive and reformative foreland basin(or thrust belt),each with distinctive petroleum system characteristics in their petroleum system components(such as the source rock,reservoir rock,caprock,time of oil and gas accumulation,the remolding of oil/gas reservoir after accumulation,and the favorable exploration area,etc.).The superimposed type foreland basins,as exemplified by the Kuqa Depression of the Tarim Basin, characterized by two stages of early and late foreland basin development,typically contain at least two hydrocarbon source beds,one deposited in the early foreland development and another in the later fault-trough lake stage.Hydrocarbon accumulations in this type of foreland basin often occur in multiple stages of the basin development,though most of the highly productive pools were formed during the late stage of hydrocarbon migration and entrapment(Himalayan period).This is in sharp contrast to the retrogressive foreland basins(only developing foreland basin during the Permian to Triassic) such as the western Sichuan Basin,where prolific hydrocarbon source rocks are associated with sediments deposited during the early stages of the foreland basin development.As a result, hydrocarbon accumulations in retrogressive foreland basins occur mainly in the early stage of basin evolution.The reformative foreland basins(only developing foreland basin during the Himalayan period) such as the northern Qaidam Basin,in contrast,contain organic-rich,lacustrine so urce rocks deposited only in fault-trough lake basins occurring prior to the reformative foreland development during the late Cenozoic,with hydrocarbon accumulations taking place relatively late(Himalayan period).Therefore,the ultimate hydrocarbon potentials in the three types of foreland basins are largely determined by the extent of spatial and temporal matching among the thrust belts,hydrocarbon source kitchens,and regional and local caprocks.     

Classification of Complex Reservoirs in Superimposed Basins of Western China

<正>Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed basins.The distinct differences between these basins and monotype basins are their discontinuous stratigraphic sedimentation,stratigraphic structure and stratigraphic stress-strain action over geological history.Based on the correlation of chronological age on structural sections,superimposed basins can be divided into five types in this study:(1) continuous sedimentation type superimposed basins,(2) middle and late stratigraphic superimposed basins,(3) early and late stratigraphic superimposed basins,(4) early and middle stratigraphic superimposed basins,and(5) long-term exposed superimposed basins.Multiple source-reservoir-caprock assemblages have developed in such basins.In addition,multi-stage hydrocarbon generation and expulsion,multiple sources,polycyclic hydrocarbon accumulation and multiple-type hydrocarbon reservoirs adjustment,reformation and destruction have occurred in these basins.The complex reservoirs that have been discovered widely in the superimposed basins to date have remarkably different geologic features from primary reservoirs,and the root causes of this are folding,denudation and the fracture effect caused by multiphase tectonic events in the superimposed basins as well as associated seepage,diffusion,spilling,oxidation,degradation and cracking.Based on their genesis characteristics,complex reservoirs are divided into five categories:(1) primary reservoirs,(2) trap adjustment type reservoirs,(3) component variant reservoirs,(4) phase conversion type reservoirs and (5) scale-reformed reservoirs.     

巴西深水盆地对比及油气成藏规律分析

对巴西东部被动大陆边缘深水盆地群的构造演化和石油地质特征进行了系统性的对比分析,研究表明,盆地群经历了4个演化阶段:前裂谷阶段、同裂谷阶段、局限海过渡阶段和被动大陆边缘漂移阶段。受区域构造应力场、膏盐层、火山岩等方面的影响,各盆地表现出不同的盆地结构和构造样式,而膏盐层的发育对于油气成藏起着关键作用。这些盆地中,主要发育了三套烃源岩、三套储层和三套区域盖层,并形成了三种油气成藏类型:盐下裂谷地堑内的构造油气藏,膏盐层上下的碳酸盐岩油气藏,以及盐上的浊积岩构造—地层复合油气藏。根据成藏规律分析,并考虑各盆地的勘探现状,按勘探潜力由好到差的顺序将盆地划分为三类,指出Ⅰ、Ⅱ类潜力区应是主要勘探方向,具有广阔的油气资源前景。