江汉盆地的构造-地质结构样式分析

江汉盆地受周缘构造作用的控制和影响,形成了南部和北部两大基底断裂体系,并控制和影响白垩-新近纪的断裂的发育,形成了多方向、不同规模的张性、压性及走滑性质的断裂或断裂系。平面上,主要断裂系呈北东或北北东向的,其次是北西向、东西向或北西西向;剖面上,形成了简单犁形、Y字型、复合Y字型、羽状、马尾状及断阶状等9种断裂组合样式。而断裂组合样式又控制了盆地的构造-地质结构样式,即江汉盆地主要有简单半地堑式、简单型的半地堑复合结构、复杂型半地堑复合式、复合地堑结构4种构造-地质结构样式。     

江汉盆地反转构造类型及分布特征

江汉盆地在陆相发展阶段，经历了早期（燕同运动晚期至喜山运动早期）的构造负反转和晚期（喜山运动晚期）的构造正反转。早期构造负反转形成的拉张断陷叠加在选期压性断裂褶皱带上，受北东向剪切带控制发育的负反转构造一般成为半地式断陷，沉积的白垩系和下第三系是江汉盆地的陆相勘的支纱；沿北西－北北西向挤压构造带分布的负反转构造成为地堑式断陷。喜山运动晚期江汉盆地发生构造正反转，时间东早西晚，反转程度东强西弱，反映     

东中国海的区域不整合

在东中国海,由于基底地堑和地垒构造作用形成了几个沉积盆地。它们都具有中新世中、晚期的侵蚀不整合面,这大概可与四万十地向斜的高千穗运动相对应。值得我们注意的是,在西北太平洋的许多地方,能看到不整合面所反映的同时期沉积间断。     

穆格莱德盆地形成特点及勘探潜力

穆格莱德盆地形成演化可分为3期：（1）早白垩世早期，随着非洲－南美泛大陆裂开，在穆格莱德产生了第一期伸展断陷盆地；（2）早白垩世晚期到晚白垩世，随着原始大西洋的产生，形成了第二期伸展断陷盆地；（3）新生代，随着区域沉降，该断陷盆地学为伸展坳陷盆地。晚白垩世末，在穆格莱德盆地南部有明显的挤压运动，形成构造反转；在盆地西北侧，沿中非大断裂带有走滑运动，使得图卢斯、巴加拉凹陷受到强烈的改造。穆格莱德盆地主要构造样式有半地堑、半地垒（或地垒）、伸展断块、滚动背斜、反转形成的挤压背斜和走滑活动形成的负花状构造等。滚动背斜、挤压背斜、地垒等构造是油气富集的主要场所。早白垩世早期充填了半深湖－深湖相的泥岩，控制了烃源岩的分布。由于沉降中心不断向南转移，在南区沉积了上白垩统优质的厚层泥岩，形成了大油田的区域盖层。上述地质条件决定了穆格莱德盆地具有良好的勘探前景。     

穆格莱德盆地形成特点与勘探潜力

穆格莱德盆地形成演化可分为 3期:(1)早白垩世早期,随着非洲南美泛大陆裂开,在穆格莱德产生了第一期伸展断陷盆地;(2)早白垩世晚期到晚白垩世,随着原始大西洋的产生,形成了第二期伸展断陷盆地;(3)新生代,随着区域沉降,该断陷盆地演化为伸展坳陷盆地。晚白垩世末,在穆格莱德盆地南部有明显的挤压运动,形成构造反转;在盆地西北侧,沿中非大断裂带有走滑运动,使得图卢斯、巴加拉凹陷受到强烈的改造。穆格莱德盆地主要构造样式有半地堑、半地垒 (或地垒)、伸展断块、滚动背斜、反转形成的挤压背斜和走滑活动形成的负花状构造等。滚动背斜、挤压背斜、地垒等构造是油气富集的主要场所。早白垩世早期充填了半深湖深湖相的泥岩,控制了烃源岩的分布。由于沉降中心不断向南转移,在南区沉积了上白垩统优质的厚层泥岩,形成了大油田的区域盖层。上述地质条件决定了穆格莱德盆地具有良好的勘探前景。     

幕式构造沉降过程中可容纳空间的变化规律——以掀斜式半地堑盆地为例

掀斜式半地堑盆地构造活动的幕式变化强调每一幕构造活动是控边断裂由强变弱的过程.这一过程变化不是盆地的简单整体沉降和可容纳空间的整体增加.在盆地不同部位,可容纳空间的变化是不一致的,那么在全盆地寻找统一的地层层序界面来建立等时地层格架就成为研究的难点.对半地堑盆地几何形态和运动过程的简化模型定量分析,表明经历一期掀斜式旋转运动后,沉降中心向缓坡带方向迁移,盆地绝对水平面是下降的,缓坡带和陡坡带均有先前水下地层的暴露,由盆缘向盆内可容纳空间不变的临界点,可容纳空间总体是变小的,但都有向盆内增加的趋势;可容纳空间在临界点之间总体是变大的,且向沉降中心都有增加的趋势.在半地堑型的博兴洼陷中,沙四段和沙三段段沉积时期4个受掀斜式构造活动所控制的层序特征证明了上述观点.这对指导建立掀斜式半地堑盆地的等时沉积层序格架具有重要的现实意义.     

东营凹陷古近纪控盆断层演化特征及盆地结构类型

东营凹陷古近纪控盆断层形态经历了早期(基本上对应于古近纪孔店组沉积时期)板式、中期(古近纪沙河街组四段到沙河街组三段早期沉积时期)铲式和晚期(沙河街组二段到东营组沉积时期)坡坪式3个阶段的演化,而断层的活动强度存在迁移性。古近系裂谷盆地各演化阶段沉积地层的空间展布与主要断层的走向基本一致,断层活动控制了盆地的沉积作用,与边界断层的演化相对应。东营凹陷古近纪盆地经历了早期旋转半地堑、中期滚动半地堑和晚期复式半地堑3个演化阶段。     

利比亚锡尔特盆地油气地质特征及有利区带预测

锡尔特盆地是利比亚最重要的含油气盆地,属北非克拉通内裂谷盆地。盆地演化经历了3个阶段:早古生代克拉通边缘坳陷、早白垩世--晚始新世裂谷和渐新世以后的坳陷阶段。发育下白垩统、上白垩统和古近系3套主要的烃源岩,其中上白垩统锡尔特页岩是最主要的烃源岩;储集层分布于基底至古近系渐新统的各个层段,前白垩系储层以碎屑岩为主,上白垩统及其上储层以碳酸盐岩为主;盖层主要为上白垩统和古近系下始新统页岩、泥灰岩和蒸发岩。受北西-南东向正断层控制,形成了一系列与断层走向一致的地垒和地堑,对应于3个大致平行的地垒隆起,可划分出西部、中部和东部3个油气聚集带,纵向上可以划分出前地堑和地堑充填阶段两大套含油层系。综合评价认为,盆地具备3类油气勘探的有利区:Ⅰ类区位于地垒带,Ⅱ类区位于地堑带,Ⅲ类区位于盆地北部海域。     

中非Muglad盆地北区构造特征

Muglad盆地发育不同规模、不同性质的断裂构造，按断层规模大小及其在盆地演化中的作用可分为基底断层和盖层断层。对Muglad盆地复杂的几何学特征分析后认为，该盆地构造单元一般以不对称半地堑形态为主，由二组走向分别为北东东向和北西向基底正断层控制的半地堑一半地垒断陷群组成。半地堑不对称交替变化是通过调节带调节其变形或位移完成的。凹陷的分割性强，各凹陷有着相对独立的构造、沉积体系，成为相对独立的烃类生成、运移和聚集基本单元。在半地堑之间发育大型正向构造调节带或大型继承性低幅度隆起，是油气高产富集区。图6参32     

渤海海域及邻区拉分构造与油气勘探领域

渤海海域及其邻区经历过断陷、断坳和坳陷三个演化阶段。断陷期基本结构单元是半地堑和半地垒,区域上分三个区,西南区是走向北北东的黄弊断陷带,断陷西断东超;中南区断陷走向呈近东西向、北东向和北西向,断陷都是北断南超的半地堑;东北区断陷带走向北北东,断陷结构东断西超。断坳期和坳陷期,凸起与凹陷统一沉降,接受盆地以外的造山带剥蚀产物。盆地演化过程中,沉降一沉积中心逐渐由边缘分别向渤中和歧口凹陷迁移。构造格局与迁移呈现出典型的地慢卷人型拉分盆地特征。渤海海域在演化过程中曾发生多期反转,以第四纪期间规模最大,形成众多成带分布圈闭。渤海海域的油气勘探领域包括凸起区、断阶带和凹中隆等背景下圈闭。     

THE DIVERSITY OF LATE NEOGENE SEDIMENTARY BASINS GENERATED BY WRENCH FAULTING IN THE EASTERN BETIC CORDILLERA, SE SPAIN

In this paper, we review the types of sedimentary basins which are generated by wrench faulting with particular reference to the Late Neogene Eastern Betic Shear Zone, a well-documented segment of the Trans-Alboran Shear Zone. The general characteristics of this wrench "corridor" are described, including the role of inherited structures. The diversity of basin types is emphasised, as is the coexistence of basins which developed under compressional or extensional regimes.
Pull-apart basins do not appear to be the most widespread type of basin in the Eastern Betic Shear Zone. Rather, compressional "groove-shaped synclines" which run parallel to master strike-slip faults (regardless of their orientation or direction of movement) are more typical structures. They are characterised by intense synsedimentary deformation and reworking of sediments, depositional processes being dominated by gravity flows. The basins are relatively short-lived and generally undergo structural inversion. Sedimentary basins also form in extensional areas, most significantly in the triangular zones which occupy the extensional quadrant of a pseudo- conjugate strike-slip fault system.
In the Eastern Betics, it appears that compressional basins are more efficient than extensional basins in terms of their subsidence and sedimentation rates, the thickness of the clastic fill, and the intensity of synsedimentary deformation. Compressional basins may therefore be the more favourable with respect to potential hydrocarbon accumulations.     

中国东部裂谷型盆地的重力构造

中国东部中新生代陆相含油气盆地是在引张体制背景下形成的裂谷型盆地,重力作用是其沉积岩变形的主导因素。盆地中的重力构造可分为滑动断阶、滚动背斜、掀斜断块、滑落背斜、滑覆构造、压实构造和底辟构造七类,它们为油气藏的形成提供了良好的圈闭条件。     

中国挤压型盆地边缘的逆冲断层是潜滑俯冲作用形成的吗?——与罗志立同志商榷

对广泛分布于中国西部和中部褶皱山系与盆地之间的逆冲断层的成因,罗志立用潜滑俯冲说进行解释,但软弱的新沉积层向早已褶皱固结的老山系下潜滑俯冲是不可能的。上述逆冲断层除少数属重力滑动构造外,主要系复式褶曲和挤压型盆地等广义纵弯褶曲的横向剪应力作用的结果,故可归属扇型逆冲断层类。     

中国东部中、新生代断陷盆地成因机制新模式

控制中国东部中、新生代断陷盆地的正断层,是水平挤压力和地壳重力共同作用下产生的、平面上和垂向上同时呈X型的压剪性断裂,与拉张作用无关.位于中、下地壳软弱层之上的上地壳刚硬层,其断裂上盘在自身重力和断裂面滑动力共同作用下,受力状态和变形情况相当于弹性基础悬臂梁,从而使盆地多呈箕状.盆地基底在沉降过程中把中、下地壳软弱层物质压向他处,造成地壳变薄,引起地幔上拱.因此,地幔隆起是断陷盆地形成的结果而不是原因.     

中大西洋被动陆缘盆地结构特征与勘探领域

中大西洋被动陆缘盆地油气资源丰富,而对盆地结构特征和成藏条件认识不足制约着区内深水油气勘探工作。综合分析地震、钻井和重磁异常等资料,以塞内加尔盆地和斯科舍盆地为重点解剖对象,研究了中大西洋被动陆缘盆地结构特征及其深水油气成藏条件并预测勘探领域。中大西洋被动陆缘盆地经历了断陷期、过渡期和漂移期三期演化,相应发育断陷层、坳陷层和陆缘层,基底性质和转换断层联合作用控制了被动陆缘盆地的结构。三叠纪—早侏罗世断陷期,发育垒堑结构,以河流、湖泊和三角洲等陆相沉积为主;中晚侏罗世过渡期,转换断裂活动形成边缘脊或海底隆起带,加之研究区古生界弱基底易拉伸减薄而沉降,与向陆方向高地势构成局限环境,为坳陷层烃源岩发育提供了有利条件;白垩纪漂移期,发育台缘礁、三角洲—坡底扇两类储集体。斯科舍盆地坡底扇和塞内加尔盆地台缘礁勘探前景广阔。     

TECTONOSTRATIGRAPHIC ANALYSIS OF THE UPPER CAMBRIAN – DEVONIAN SEDIMENTARY SUCCESSION IN THE CENTRAL DARLING BASIN,SE AUSTRALIA: AN INTEGRATED INTERPRETATION OF SEISMIC,GRAVITY AND WELL DATA

This paper presents a tectonostratigraphic interpretation based on seismic, gravity and well data of the Upper Cambrian through Devonian sedimentary succession in the central part of the Darling Basin, New South Wales (SE Australia). A composite roughly north‐south trending 2D seismic section through this area, tied to two exploration wells, defines four unconformity‐bound second‐order seismic megasequences. The megasequences are: A, Upper Cambrian – Middle Ordovician (Llanvirnian?); B, uppermost Silurian – Lower Devonian (Emsian); C, upper Lower Devonian – lower Middle Devonian (Givetian); and D, upper Middle Devonian – Upper Devonian (Famennian). The megasequences are bounded by prominent seismic marker horizons which represent phases of regional‐scale orogenic activity. The composite 2D section studied is about 150 km long and traverses from north to south the Pondie Range sub‐basin, the inverted Wilcannia High and the Blantyre sub‐basin. Along the section, the Upper Cambrian to Devonian succession is deformed into a series of large‐scale, fault‐associated anticlines and synclines including the Avon High, an asymmetric anticlinal fold associated with several high‐angle reverse faults. Major faults extend into, and flatten within, the basement. The top‐basement surface is characterized by broad highs and lows which are represented on a gravity map of the study area. The map shows that the Wilcannia High defines the northern margin of the Blantyre sub‐basin and the southern margin of the Pondie Range sub‐basin. These sub‐basins are in general defined by gravity lows. The development of the Blantyre and Pondie Range sub‐basins can be divided into five tectonostratigraphic phases during which there were distinct patterns of fault activity and regional subsidence. These phases are investigated using a restoration model which involves the successive removal of each seismic megasequence in turn, assuming simple vertical shear. The model provides new constraints on the distribution of structural and stratigraphic features which are relevant for future hydrocarbon exploration.     

合肥盆地重力场特征

合肥盆地地质构造复杂,地表沟壑纵横,通过对重力异常目标处理,揭示基底特征及断裂、构造发育情况,认为本区南北分区,"众凹环隆"。该文应用重、磁、电、震等综合物探资料,将本区划分为前陆冲断带、舒城前渊沉降带、六安前隆断褶带和肥北隆后斜坡带4个勘探区带。指出了下步勘探方向和勘探前景。     

STRUCTURAL AND TECTONIC SYNTHESIS FOR THE PERTH BASIN, WESTERN AUSTRALIA

The Perth Basin is localised by reactivation of Neoproterozoic shear zones on the western margin of the Archaean Yilgarn Craton in Western Australia. While Ordovician to Silurian sandstones were deposited in the northern Perth Basin, the earliest sediments elsewhere are Middle Carboniferous to Permian in age. A sinistral transtensional regime, during which the main architecture of the basin was established, developed during NE-SW extension between Greater India and Western Australia in the Permo-Triassic. NW-SE shortening with continued NE-SW extension resulted in sinistral transpression in the late-Early to Middle Triassic. Sag-phase sedimentation in the LateTriassic followed this oblique rifting event. An analogy may be made between the Perth Basin and the Permo-Carboniferous to Jurassic Karoo basins in southern and central Africa and Madagascar. Deposition of the Karoo sequence took place within pull-apart and transtensional basins resulting from sinistral reactivation of basement shear zones. The Indian Gondwana Supergroup, and an equivalent sequence in Antarctica, were deposited within normal fault-bounded graben. The Late Paleozoic to Early Mesozoic formation of the Perth Basin, the Karoo basins of Africa and Madagascar, and the Gondwana basins of India was due to intraplate stress resulting from convergence along the Panthalassa margin of Gondwanaland. Late-Early to Middle Triassic compressional events in all basins mark terminal collision along the Panthalassa margin. The latest Triassic to Early Jurassic marks a new rifting event due to regional east-west to WNW-ESE extension, producing dextralplus normal displacements on many NW-to NNW-striking structures, and essentially normal displacements on north- to NNE-striking faults. NW-SE extension during the Upper Jurassic culminated in the NW separation of Greater India and the formation of oceanic crust in the Neocomian, and resulted in the superposition of structures developed in a dextral transtensional regime. Conjugate strike-slip faults and minor thrust faults formed during the post-Neocomian, with approximately north-south compression and east-west extension. Precambrian gneisses, granitoids and metasediments of SW Western Australia have been deformed during basin development, and dole rite dyke intrusion during the Carboniferous to Middle Triassic is restricted to these terranes. The sequence of events proposed herein for the Perth Basin is in agreement with the tectonic framework of a large portion of Gondwanaland. A better knowledge of the structural history of the Perth Basin may aid the interpretation of seismic and remote-sensing data in the search for further hydrocarbon occurrences.     

复杂深水重力构造勘探研究新方法——以尼日尔三角洲深水区A构造为例

针对用常规解释方法和相干体技术对尼日尔三角洲复杂深水重力构造进行断层解释失效的状况,提出了复杂深水重力构造勘探研究新方法,即层位解释—断层解释—断层剖面地质模式确定—断层平面特征分析的综合研究思路。创新性地应用沿层平均瞬时相位技术代替常规相干分析技术进行断层平面组合,提高了断层解释的精度和效率,解释结果更加符合重力构造形成的地质规律。在此基础上,建立了复杂深水重力构造"树状"断裂体系模式,并提出了"爬树法"的分析模式,对"树状"断裂体系进行级别和期次划分,并确定了断层对油气输导和分割的双重作用,为今后复杂深水重力构造的勘探开发奠定了基础。     

中国各类陆相盆地斜坡区大中型岩性型油气田形成特征

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