库车前陆盆地克拉苏构造带的构造特征与油气

克拉苏构造带位于库车前陆盆地的北侧,由浅部和深部两个层次的构造组成、上、下同层次的构造具有不一致性。浅部层次的构造主要为断层传播褶皱、断层传播－滑脱褶皱,这些构造的突破断层发育,不利于油气的保存;深部层次的构造主要为被动顶板双重构造、突发构造和断层转折褶皱,这些构造在走向上相互转变,构成了本区最有利的构造圈闭。断裂是本区最重要的构造,它不仅是烃源岩排烃的有效机制、而且是油气运移的通道。     

孟加拉湾若开盆地构造特征及演化

根据地震、钻井等基础资料建立主干剖面,结合平面构造展布及剖面构造特征研究孟加拉湾若开盆地的构造特征和演化。若开盆地是一个主动大陆边缘海沟背景下的增生楔盆地,经历了晚白垩世-古新世早期发育期、始新世-渐新世缓慢碰撞期和中新世-上新世盆地定型期3个区域演化阶段。平面上划分为东部的若开褶皱带和西部的海底平原带。若开褶皱带具有南北分段特征,根据构造特征差异分为2段:(1)北段挤压褶皱带,主要发育NNW走向、带状分布褶皱。北段挤压褶皱带可分为高陡褶皱带和低缓褶皱带2个次一级构造单元,变形强度从东往西逐渐减弱。(2)南段走滑褶皱带,褶皱表现为宽度较窄,并发育明显走滑构造。主干剖面构造演化史分析认为:研究区构造变形开始于晚中新世末,上新世末-第四纪变形强烈;构造变形从东向西传播,东部变形时间早,变形强烈,而西部变形时间晚,变形较弱;在中新统沉积后,区域构造发生翘板式逆时针旋转,沉积中心从东部迁移到西部。若开盆地的构造形成与演化主要受印度板块向欧亚板块斜向B型俯冲碰撞控制,由于俯冲碰撞接触带在若开盆地呈弧状,南北两段应力场不同,导致南北两段构造变形存在明显差异。     

六盘山盆地西南缘构造与油气勘探潜力分析

六盘山盆地是在古生代褶皱基底上发育起来的中新生代沉积盆地.地面构造调查、地震与非地震勘探表明,喜马拉雅运动以来,在盆地西南缘山带发育由多条逆冲断层及夹于其中的逆冲席所组成的复杂的叠瓦型冲断构造,该构造带与酒西盆地祁连山山前带具有类似的构造特征和油气成藏背景,成藏地质条件优越,是六盘山盆地最有利的油气勘探区之一.     

独山子背斜构造演化序列及其对油气成藏的控制

独山子背斜位于准噶尔南缘四棵树凹陷,背斜北翼陡南翼缓,北翼近于直立,造成背斜北翼地震剖面呈现空白区。通过二维地震反射剖面和钻井资料精细构造解析,结合正演以及运动学数值模拟技术,提出独山子背斜构造模型:独山子背斜发育上、下两套滑脱层,下部滑脱层发育断层转折褶皱,上部滑脱层发育三角剪切型断层传播褶皱,构成一个叠加背斜构造。独山子背斜中上组合构造发育喜马拉雅运动期3期构造演化序列,即早期(N2d沉积时期)转折褶皱、中期(Q1沉积时期)传播褶皱及晚期(Q4沉积时期)冲断改造。喜马拉雅运动期3期构造演化序列控制了独山子背斜中上组合油气运聚与油气藏展布特征。     

龙门山南段前缘构造砂箱变形模拟实验

基于地球物理、测井资料设计构造砂箱变形模拟实验,再结合断层相关褶皱理论来研究龙门山南段前缘地区构造变形特征。单层硅胶层与无硅胶层实验模型对比表明单层硅胶层模型更吻合实际的地震剖面,硅胶层的存在使深部构造保存得更为完整,变形强度要弱于无硅胶层实验。通过实验结果,更为精准地解释了地震剖面,从地震剖面可以看出,从造山带向盆地横向上构造活动减弱;在盆地内,中三叠统雷口坡组厚层膏盐岩作为滑脱层,吸收了大量应力,影响了纵向上的构造变形,滑脱层之上的构造变形强于其之下的地层:褶皱隆起的幅度更强,断层更为发育但较难突破滑脱层向下发展。实验证明在滑脱层中,应力无法传播很远,断层只能被局限在一定的范围内发展。研究结果对于研究区变形特征以及深层构造特征研究有重要意义,对于该区深层特别是滑脱层之下油气勘探有一定的借鉴意义。     

Maranon盆地油气地质特征及勘探潜力

以地质、地球物理数据为基础,结合前人研究成果,对Maranon盆地演化与油气地质特征进行了详细的分析.研究表明:Maranon盆地是一多旋回次安第斯山前陆盆地,经历了古生代克拉通期、三叠纪—侏罗纪伸展断陷期、白垩纪拗陷期和晚白垩纪后前陆期4个构造演化阶段,纵向沉积地层可划分为前白垩系、白垩系和后白垩系3套巨层序.盆地内含有白垩系Chonta/Napo组和三叠—侏罗系Pucara组2套主力烃源岩及多套储盖组合.油气运移方式为垂向运移、侧向运移和阶梯式运移.盆地主要发育西部挤压断层和褶皱圈闭、中部背斜和披覆背斜圈闭、东部断层和牵引背斜圈闭等构造圈闭,可能发育岩性、地层圈闭.不同类型圈闭呈北西—南东向条带状分布.前陆坳陷带构造-地层和岩性圈闭、褶皱冲断带区古近纪构造圈闭以及东部斜坡带地层和岩性圈闭是盆地的有利勘探潜力区.     

四川盆地下二叠统断层与缝洞发育关系研究

四川盆地下二叠统碳酸盐岩为典型的缝洞型储层，断层带钻探获得了较好的效果。较多的研究认为断裂带是有利的裂缝发育带并沿裂缝形成溶洞，研究发现地表剖面溶洞充填物被断层切割错动，溶洞次生方解石充填物中可见沥青质包裹体和沥青团块，沥青物质为原油裂解成天然气后残留，而石油裂解成气的时间远早于构造断层菜成期，钻井质资料统计表明，放空的井次在断点附近并没有明显优势，放空井段通常造近侵蚀面顶部，而断层带以裂缝发育为主，因此，下二叠统储层中溶并非断层裂缝形成后的产物，溶洞发育时间在构造褶皱，断层形成之前，而构造褶皱，断层发育后并发未发生较大规模的岩溶作用。     

塔里木盆地巴楚褶皱带构造几何学及其构造物理模拟

基于精细的构造几何学和运动学观测, 结合砂箱模拟实验结果分析, 将塔里木盆地巴楚褶皱带解释为不同规模膝褶带形成的大型背斜构造, 与断裂作用无关。新解释强调巴楚褶皱带为膝褶型背斜变形, 系膝褶带围限而形成的褶皱。该类型构造具有如下几何学特征: 带内地层发生一定角度的倾斜, 具有一定宽度, 膝褶带两侧边界近于平行, 膝褶带与带外地层呈高角度关系, 部分膝褶带呈共轭出现。砂箱模拟实验重现了盆地腹地膝褶带发育和演化的全过程: 宽缓拆离褶皱→紧闭拆离褶皱→褶皱突起→断层调节改造作用, 模拟结果证明膝褶带是巴楚隆起形成过程的重要构造要素之一。     

南堡凹陷Ⅱ号、Ⅲ号构造带断裂构造发育特征及成因

基于渤海湾盆地北部南堡凹陷三维地震解释数据,以盆地构造解析理论为指导,系统梳理南堡凹陷Ⅱ号和Ⅲ号构造带内断裂几何特征及组合样式,结合平衡剖面技术恢复不同构造活动时期盆地发育特征,探讨断裂变形的成因机制。结果表明：南堡Ⅱ号、Ⅲ号构造带是典型的伸展构造样式,平面上以NEE走向平行对倾式为主要组合样式,剖面上呈“似花状”构造。根据断距-埋深曲线厘定,南堡凹陷Ⅱ号、Ⅲ号构造带内断裂系统分为基底先存断裂系统、晚期新生断裂系统和长期活动断裂系统。沙河街组沉积时期,南堡凹陷Ⅱ号、Ⅲ号构造带内形成NE向主干边界断层;东营组沉积时期,形成反向边界断裂,与主干断裂构成“y”字形结构样式;馆陶组-明化镇组沉积时期新生大量NEE向断层与长期活动主干边界断裂共同构成密集断裂带。先存基底F₂、F₃断层影响着局部应力场的分布,与上覆构造带构成间接关联耦合关系,先存基底与控带断层构成铲式扇组合共同控制浅部断裂密集带的发育。成因上,南堡凹陷Ⅱ号、Ⅲ号构造带的形成与发育直接受控于古近纪以来太平洋板块俯冲方向的转变。     

秋立塔克构造带盐构造形成的传力方式的构造物理模拟

库车坳陷第三系下部库姆格列木群是一套巨厚的膏 (盐 )层 ,该层系不管是在应力传递方面 ,还是在控制构造样式方面都有重要的作用 .秋立塔克构造带是库车前陆褶皱冲断带的变形前缘 ,盐上、盐下构造极不协调 ,盐上层变形强烈 ,发育滑脱断层、大型推覆构造、突发构造和三角带构造 ;盐下变形弱 ,发育小规模的冲断层 .根据构造分析推断 ,在盐上层中 ,应力从变形后缘 (克拉苏构造带 )向变形前缘秋立塔克构造带的传递有 2种方式 ,即重力滑动传递和顺层挤压传递 .构造物理模拟实验证明这种推断是合理的     

断弯褶皱和断展褶皱中的油气运移聚集行为

断弯褶皱和断展褶皱是前陆冲断带中的两种典型构造形式.运用有关断层中流体运移和封堵理论及方法,结合塔里木盆地库车前陆冲断带的油气勘探实例,对断弯褶皱和断展褶皱中油气运移和聚集行为进行分析讨论.初步认为断展褶皱中的油气运移与聚集能力优于断弯褶皱。具体特征表现在断弯褶皱中是:1)台阶状逆断层具有较强的封堵能力,使得其上、下盘构造被隔离为两个不同的油气运移与聚集体系;2)上盘背斜圈闭中的油气主要来自于褶皱后翼的向斜凹陷;3)背斜圈闭中的储层有可能被轴面变形条带分隔为3个隔离油气舱;在断展褶皱中其特征是1)断层端点的扩展作用过程,就是在断层阀机制作用下,油气沿断层带从下部地层向上部背斜核部运移输送的过程.2)断层上、下盘及背斜两翼可以构成一个统一的油气运移聚集体系.3)背斜储层中的油气往往处于异常流体压力状态.     

龙门山南段推覆构造与前陆盆地演化

龙门山南段推覆构造带可划分为四个亚带：陇东褶皱推覆构造带、宝兴冲断推覆构造带、中林－双石薄皮推覆构造带、前陆褶皱构造带。依据龙门山南段推覆构造样式、变形特征及前陆盆地的沉积特征,论述了龙门山南段推覆构造和前陆盆地的同步演化历史。     

Quaternary folding in the south piedmont of central segment of Tianshan Mountains

The Tianshan Mountains are an important active structural belt in the interior of Eurasia. By integrated methods of surface geology survey and interpretation of seismic profiles, we distinguish fold scarps located at the south limb of the Kuqatawu anticline and the north limb of the Dongqiulitag anticline in the Kuqa rejuvenation foreland thrust belt, south piedmont of central segment of the Tianshan Mountains. Fold scarp is a newly found structural phenomenon. Because of the bend of thrust plane and the movement of hanging wall above the thrust plane, the original horizontal deposits of hanging wall and their surface become a monocline structure, resulting from the separating and migration of the active and fixed axial surfaces. Measuring the geometry of fold scarp and using the data of age of the deformed deposits, the crustal shortening rate resulting from the deeply seated subsurface thrust is calculated. The crustal shortening rate reflected by the fold scarp located at the north limb of the Dngqiulitag anticline is (1±0.1) mm/a. The fold scarps of the Dongqiulitag anticline and the Kuqatawu anticline identify that the deformation process of the crustal compressive structures in the Kuqa area extends into the Late Quaternary.     

Structural characteristics and petroliferous features of Tarim Basin

Using the modern tectonic geology theories andmethods such as the plate tectonic analysis, the paleo-struc-ture analysis, the structural-Iithofacies analysis, and the faultrelated fold and petroleum system, and combining with theseismic data, well drilling data and the circumferential fieldgeology, study on the structural characteristics and petro-leum prospect in the Tarim Basin has been carried out. Re-sults show that the Tarim Basin is a large superimpositionand combination basin with continental crustal basement,composed of a Paleozoic craton and Meso-Cenozoic forelandbasins. The characteristics of the basin are: the kernel partof the basin is the marine facies Paleozoic craton, superim-posed 4 continental facies foreland basins. Though the scaleof the paleozoic craton of the Tarim Basin is relatively small,the structure is steady. The petroleum prospect of the Paleo-zoic craton is: multiphase pool-generation and accumulationcontrolled by ancient uplift. The Meso-Cenozoic forelandbasins in the Tarim Basin, which are distributed on the era-tonic circumference and are a long-term subsidence, turnedinto rejuvenated foreland basins after the Meso-Cenozoicperiod. The petroleum prospects are: coal-bed generatinghydrocarbon, abundant natural gas, pool-generation in laterand recent periods, the oil and gas distribution controlled bythe foreland thrust belt. The structural characteristics ofTarim provide it with a superimposition and combinationpetroleum system of multiple resources, multiple reservoirsand multiphase pool-generation. The oil and gas explorationprospect covers two large fields: the Paleozoic craton and theMeso-Cenozoic foreland thrust belt.     

龙门山山前带北段油气远景评价

龙门山系属上扬子地台内晚中新生代断褶活动形成的山系。川西断陷属龙门山系的前陆盆地，是地台型海相沉积和前陆型陆相沉积组成复合型的含油气区。新生代断褶构造发育程度控制了山前带构造圈闭的发育和裂缝性气藏的形成。印支晚期天井山古隆起因受喜马拉雅期强烈断褶上升活动，使原有的油气藏遭到破坏。天井山古隆起北东倾伏端的广元地区，发育隐伏断裂系伴生的背斜群，是较理想的油气聚集区。     

东北地区白垩纪断陷盆地群形成模式及其油气地质意义

东北地区白垩系断陷盆地群是在古生代褶皱造山带的基础上发展起来的早白垩世宽范围火山断陷盆地群,经历了一个完整的拉张断陷到挤压回返的构造旋回,伸展作用强烈,坳陷广泛发育,具有构造样式复杂、垒堑相间、断超结构的特点。郯庐断裂带北段在早白垩世发生的左旋走滑运动控制了断裂带两侧盆地的发育。中生代断陷盆地群是在较新的地壳上发展起来的,中酸性火山活动强烈,在松辽盆地和海拉尔盆地存在两个岩石圈减薄区。断陷盆地群具有相似的构造特点,火山断陷作用强烈。在前人研究的基础上,证实了松辽盆地存在裂前隆起。本文从裂谷成盆模式模式入手,认为断陷盆地群东部是窄裂谷成盆模式,西部及中部是宽裂谷成盆模式,认为东北断陷盆地群是在幔隆过程中形成。     

Magnetic fabrics in fault-related fold and its relation with finite strain: an example from Mingjiang thrust structures in Western Sichuan

The anisotropy of magnetic susceptibility (AMS) is a quick, effective and sensitive technique used to measure the weakly deformed sedimentary rocks, and also a reliable method to reveal the deforming mechanisms of fault-related folds. In Longmenshan front belt, a typical cross-section of fault-related folds is chosen to study the AMS. A total of 224 oriented specimens have been drilled at 23 different sampling sites which were distributed at the key structural positions of this structural section developed in the Xujiahe formation of the upper Triassic. Six elementary types of magnetic fabrics are recognized and established through this AMS study: 1) a sedimentary fabric; 2) an initial deformation fabric; 3) a pencil structure fabric; 4) a weak cleavage fabric; 5) a strong cleavage fabric; 6) a stretching lineation fabric. It has been found that most of magnetic fabrics are characterized by fabrics of weak deformation which belong to the pure-shear results of a pre-folding layer parallel shortening (LPS). In the fault-bend fold, almost all magnetic fabrics are the initial deformation fabrics of weak deformation, and denote that the deformation in the forelimb is stronger than that in the backlimb and no finite strain is shown in the footwall. While in the fault-propagation fold， finite strains are concentrated in the trishear zone where magnetic fabric results are approximately consistent with the estimated consequences of the kinematic model. The tectonic stress field indicated by the magnetic fabrics is basically the same along the whole structural section and shows a NW to SE compression and shortening which is accordant with the regional compressive stress field of the Longmenshan fold-thrust belt.     

Magnetic fabrics in fault-related fold and its relation with finite strain: an example from Mingjiang thrust structures in Western Sichuan

The anisotropy of magnetic susceptibility (AMS) is a quick, effective and sensitive technique used to measure the weakly deformed sedimentary rocks, and also a reliable method to reveal the deforming mechanisms of fault-related folds. In Longmenshan front belt, a typical cross-section of fault-related folds is chosen to study the AMS. A total of 224 oriented specimens have been drilled at 23 different sampling sites which were distributed at the key structural positions of this structural section developed in the Xujiahe formation of the upper Triassic. Six elementary types of magnetic fabrics are recognized and established through this AMS study: Da sedimentary fabric; 2) an initial deformation fabric; 3) a pencil structure fabric; 4) a weak cleavage fabric; 5) a strong cleavage fabric; 6) a stretching lineation fabric. It has been found that most of magnetic fabrics are characterized by fabrics of weak deformation which belong to the pure-shear results of a pre-folding layer parallel shortening (LPS). In the fault-bend fold, almost all magnetic fabrics are the initial deformation fabrics of weak deformation, and denote that the deformation in the forelimb is stronger than that in the backlimb and no finite strain is shown in the footwall. While in the fault-propagation fold, finite strains are concentrated in the trishear zone where magnetic fabric results are approximately consistent with the estimated consequences of the kinematic model. The tectonic stress field indicated by the magnetic fabrics is basically the same along the whole structural section and shows a NW to SE compression and shortening which is accordant with the regional compressive stress field of the Longmenshan fold-thrust belt.     

龙门山南段前陆冲断带内的古油气藏

通过对龙门山南段地表沥青发育特征及分布规律的研究,对比不同层位中流体充注特征,结合该地区构造演化史,证实了龙门山南段冲断带内曾经存在过古油(气)藏,重塑了古油(气)藏形成和破坏的过程。研究表明,沥青主要分布于观雾山组和灯影组次生溶孔、溶洞和裂缝中;以灯影组中沥青最为发育,侧向延伸稳定,垂向充填较厚,说明研究区曾存在过古油(气)藏。晚三叠世以前,来源于松潘-甘孜海盆的油藏流体,由西向东运移充注于现今前陆冲断带内的震旦系灯影组、泥盆系和二叠系储集空间中形成古油藏;晚三叠世盆山转换时期,古油藏随着前陆盆地的快速沉降而被深埋,油裂解成气而形成古气藏;随着冲断带向前陆盆地扩展,赋存于前陆盆地内的古气藏被破坏。     

塔里木盆地库车褶皱冲断带的构造特征与油气聚集

根据地面地质调查和地震剖面解释 ,认为库车褶皱冲断带具有分带组合的构造特点 ,即由南侧的滑脱褶皱和北侧的断展褶皱相互匹配 ,实例有喀桑托开背斜与吉迪克背斜、吐孜麻扎背斜与大宛齐背斜、亚克里克背斜与米斯坎塔格背斜以及东秋里塔格背斜与亚肯背斜等 .除了南北分带、上下分层和东西分段特征外 ,库车褶皱冲断带还具有构造分块特点 ,自西向东依次可分却勒、克拉、迪那和阳霞 4大区块 .库车褶皱冲断带的油气聚集主要与侧断坡相关背斜有关