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1.
正断层的分段构造型式及其扩展演化机制的核心内容可以归结为正断层的中继构造模式。本文从正断层的断块变形、断裂扩展以及断裂力学特征等角度,总结了正断层中继构造的扩展演化机制。正断层的断块变形是指分段断层位移转换形成的中继斜坡,可分为内倾和外倾两种斜坡类型,位移曲线揭示了中继带变形的特征。正断层的断裂扩展有多种扩展方式,可分为断层内、断层间和断层系扩展,且可以形成不同型式的中继构造。正断层中继构造是在三维空间扩展的,将断层边缘的断裂力学性质和断层面的放射状扩展方向相结合,可完整描述中继构造的空间分布规律。正断层形成于伸展构造环境,是控制油气和金属矿产资源的重要构造型式,结合SEDEX型矿床同生断层和岩体侵位控制的正断层控矿研究实例,初步讨论了正断层中继构造扩展演化在SEDEX型矿床和正断层相关控矿断裂成矿构造研究中的作用。 相似文献
2.
黄河口凹陷东洼是渤海盆地典型的盆缘洼陷,基于新一轮区域三维地震精细解释资料,采用构造解析与构造物理模拟技术相结合的方式,对黄河口凹陷东洼的断裂体系特征与构造演化过程进行研究.研究表明,受走滑和伸展变形的共同作用,研究了发育了以NNE-NE走向为主的走滑断裂体系和以EW-NEE走向为主的伸展断裂体系,断裂构造演化经历了孔店组-沙四段沉积时期的初始张扭裂陷阶段、沙三段沉积时期的走滑伸展裂陷阶段、沙一二段和东营组沉积时期的伸展萎缩持续走滑阶段、馆陶组和明化镇组沉积时期张扭变形阶段等4个阶段.其中,主走滑断层是在初始张扭裂陷阶段所形成的NE向伸展断层基础上持续活化而成;主伸展断层则形成于走滑伸展裂陷阶段的SN向伸展作用应力背景下.在伸展萎缩持续走滑阶段,各方位断裂在近SN向伸展作用下持续再活动,表现为走滑-伸展复合变形为主;在张扭变形阶段,先期主干断裂选择性活动,同时新生形成大量新近系的次级断层. 相似文献
3.
利用最新三维地震解释成果,结合钻井和区域地质资料,运用断裂生长指数、平衡地质剖面、趋势厚度恢复等多种方法对马北地区断裂组合、断裂发育期次、断裂演化、构造高点发育及迁移规律进行了精细解剖。依据断层组合关系、安德森断层模式及Harding1974年关于走滑断裂系应力、应变的相关论述,对该地区新生代以来各地质历史时期的应力状态进行了探讨,并以油气动态成藏的方式系统地研究了断裂-构造高点演化与油气藏之间的耦合关系,认为马北地区多期断裂是以马仙断裂为主导的走滑断裂体系,其断裂演化与马仙断裂活动息息相关,且与古今构造之间具有明显的耦合关系,两者共同控制了新生代油气藏的形成、改造及分布。 相似文献
4.
断裂是黄骅坳陷新生代主要构造变形类型,对该区油气成藏有重要影响。本文将黄骅坳陷中区的断裂划分为6个系统,并综合分析了它们之间的关系。每一断裂系统至少有一条主干基底断层,发育在该断层上、下盘的次级断层以不同形式与主干基底断层组合在一起,其剖面上的构造样式和平面上的构造组合显示了该断裂系统在新生代的运动学特征。在系统分析黄骅坳陷中区新生代断裂系统的断层组合、构造样式、主干断层位移方式及生长史的基础上,结合区域构造背景、伸展边界条件及断层间的相互作用,探讨了该区断裂系统的形成机制。分析结果表明:区域构造背景下存在的伸展边界控制了整个黄骅坳陷中区新生代断裂系统总的构造格局,系统中主要断层走向与伸展边界近于平行。这进一步证实了区内右旋走滑作用与伸展作用的相互耦合,致使断层沿走滑构造带出现转向或中断。各断裂系统之间及系统内部断层间的运动学关系表明黄骅坳陷古近纪受两个构造动力控制,一是地幔热作用引起岩石圈北西—南东向引张作用,二是北北东向深断裂带的右旋剪切作用。 相似文献
5.
渤海湾盆地张巨河复杂断块区平面砂箱模拟实验及其启示 总被引：7，自引：0，他引：7
伸展盆地复杂断块区往往发育多个方向的断层，这种复杂的正断层组合过去有人认为是多期构造矗加作用的结果。本文针对渤海湾盆地张巨河复杂断块区进行了平面砂箱模拟实验。实验结果表明，在基底有先存构造(如基底断裂)的情况下，如果区域伸展方向和先存断裂或基底构造活动(底辟上拱)不协调，通过递进变形就可以形成复杂的断层组合，即复杂的断层组合可以在一个伸展构造期内、在统一的区域伸展构造力作用下在递进变形过程中逐渐形成，复杂断层组合并不一定需要多期变形叠加。在此基础上，结合理论分析，提出了复杂断层组合成因的另一种模式——不协调伸展递进变形模式。该模式为揭示伸展构造系统中复杂断层组合之间的内在联系提供了新的思路。 相似文献
6.
基于“同一应力场不同边界条件形成不同性质断层”的构造解析原理,认为海拉尔盆地断陷期受南南东—北北西向拉张应力场作用,形成北北东和北东东向断裂,北北西向断裂明显走滑变形.断-坳转化期拉张应力场方位调整为近东西向,形成近南北向断裂,北北东、北东东和北北西向断裂扭动变形.伊敏组沉积末期盆地回返,受近东西向挤压应力场控制盆地左旋压扭变形,北北东和北东东向断裂强烈反转.依据断裂变形特征叠加关系,海拉尔盆地形成4套断裂系统:早期伸展断裂、中期张扭断裂、早期伸展中期张扭断裂和早期伸展中期张扭晚期反转断裂.断陷构造层早期伸展中期张扭反向断裂形成断层遮挡圈闭,早期伸展断裂将凹中隆和斜坡切割破碎形成断层复杂化的背斜圈闭,早期伸展断裂与中期张扭断裂交叉组合,形成复杂的断块圈闭.断-坳构造层早期伸展中期张扭晚期反转断裂呈“梳状”组合,形成典型的断块圈闭.基于断裂活动时期与成藏期耦合关系以及典型油气藏解剖的结果认为,早期伸展和早期伸展中期张扭断裂在成藏关键时刻为遮挡断层,且封闭的烃柱高度一般均小于圈闭的幅度,早期伸展中期张扭晚期反转断裂为调整型断层.基于圈闭的样式、断层在成藏中的作用及输导体系分析,海拉尔盆地断裂控藏模式分为二型4类,二型为原生油藏和次生油藏.原生油藏包括3类:一是灶缘油气侧向运移反向断层遮挡成藏模式,控藏断裂为早期伸展中期张扭断裂系统;二是灶内油气初次运移断层遮挡“箱内”成藏模式;三是灶内凹中隆油气侧向运移“弥散式”成藏模式.这两种模式控藏断裂均为早期伸展断裂.次生油藏为油气沿断裂垂向运移“伞式”成藏模式,控藏断裂为早期伸展中期张扭晚期反转断裂系统. 相似文献
7.
广济-九江同步耦合断裂及其控岩、控矿作用 总被引：2，自引：0，他引：2
与广济－九江同步耦合断层对应的NNE向断裂（郯庐断裂、赣江断裂）经历了三次性质转变：J3－K1（157－97Ma)为左行走滑,K1晚期至E2为张性拱裂,E2－3以后呈右行走滑;在广济－九江同步耦合断层的耦合区内相应形成了伸展褶断、扭旋褶断、挤压褶断三种构造组成形式,其中燕山早期的伸展褶断构造组合呈现出张性伸展性质,为成岩成矿提供有利空间;同步耦合区内形成于燕山早期第二、三阶段的堑垒式褶断构造和燕山晚期第一阶段的扭旋褶断构造是控制成矿岩体及矿床定位的具体构造形式。 相似文献
8.
基于"同一应力场不同边界条件形成不同性质断层"的构造解析原理,认为海拉尔盆地断陷期受南南东—北北西向拉张应力场作用,形成北北东和北东东向断裂,北北西向断裂明显走滑变形。断-坳转化期拉张应力场方位调整为近东西向,形成近南北向断裂,北北东、北东东和北北西向断裂扭动变形。伊敏组沉积末期盆地回返,受近东西向挤压应力场控制盆地左旋压扭变形,北北东和北东东向断裂强烈反转。依据断裂变形特征叠加关系,海拉尔盆地形成4套断裂系统:早期伸展断裂、中期张扭断裂、早期伸展中期张扭断裂和早期伸展中期张扭晚期反转断裂。断陷构造层早期伸展中期张扭反向断裂形成断层遮挡圈闭,早期伸展断裂将凹中隆和斜坡切割破碎形成断层复杂化的背斜圈闭,早期伸展断裂与中期张扭断裂交叉组合,形成复杂的断块圈闭。断-坳构造层早期伸展中期张扭晚期反转断裂呈"梳状"组合,形成典型的断块圈闭。基于断裂活动时期与成藏期耦合关系以及典型油气藏解剖的结果认为,早期伸展和早期伸展中期张扭断裂在成藏关键时刻为遮挡断层,且封闭的烃柱高度一般均小于圈闭的幅度,早期伸展中期张扭晚期反转断裂为调整型断层。基于圈闭的样式、断层在成藏中的作用及输导体系分析,海拉尔盆地断裂控藏模式分为二型4类,二型为原生油藏和次生油藏。原生油藏包括3类:一是灶缘油气侧向运移反向断层遮挡成藏模式,控藏断裂为早期伸展中期张扭断裂系统;二是灶内油气初次运移断层遮挡"箱内"成藏模式;三是灶内凹中隆油气侧向运移"弥散式"成藏模式。这两种模式控藏断裂均为早期伸展断裂。次生油藏为油气沿断裂垂向运移"伞式"成藏模式,控藏断裂为早期伸展中期张扭晚期反转断裂系统。 相似文献
9.
下扬子海陆域新生代沉积盆地是中国东部主要含油气盆地之一,成盆断裂特征与活动规律是该区油气勘探研究的基
础。文章基于高覆盖率的地震勘探测线,以构造断裂解析为突破口,探究盆地断裂的变形特征与活动规律。依据断裂组合
样式与构造活动特征,断裂可分为伸展、走滑、挤压-反转三种样式,构造活动分为伸展断裂与伸展-走滑断裂两种构造
体系。成盆断裂显著受控于郯庐断裂右行走滑变形,主要与郯庐断裂带不同构造走向的区段位置和与郯庐断裂带的距离这
两个因素或变量有关,盆地断裂呈现了“东西有别,中部不同”的特点。下扬子区新生代多变应力场,控制着作为油气运
移通道断裂的开闭状态,是油气资源评价的重要依据。 相似文献
10.
甘肃礼岷金矿田的中继构造及其控矿作用 总被引：3，自引：0，他引：3
对甘肃礼岷金矿田控矿断裂的组合形式和力学性质的分析表明具有中继构造的模式，矿体为正断层带，呈不连续的错位排列，错位矿体的排列型式受基底构造控制，矿体的构造变形较弱，显示了断层带发展初期的特征。矿体在深部有规模扩大的趋势，与控矿断裂从深部向浅部的扩展顺序有关，这是岩体接触带构造环境和矿液压裂作用的结果。 相似文献
11.
Three dimensional seismic-reflection data from the western Niger Delta were used to investigate the segmentation and linkage of a syn-sedimentary normal fault array and to estimate the influence of a pre-existing normal fault on the geometry and growth of younger faults. The nucleation, growth and linkage of a regional (seaward-dipping) deltaic fault system were analyzed on reflectivity time-/horizon slices and vertical seismic sections. In the deep subsurface, a master fault that consists of two segments (northwestern, NW, and southeastern, SE) grew through time into a single fault by lateral tip propagation reaching a final length of about 15 km. After attaining this length, displacement along the fault system developed non-uniformly through time. The analysis of the hanging-wall sediments of the deep-seated master fault shows two different processes of vertical linkage above the NW and SE segment. The SE segment links vertically to several younger faults contemporaneously with displacement accumulation on the master fault; in contrast, fault linkage above the NW segment occurred only after an interval of master-fault inactivity connecting the deep-seated structure upwards to a single syn-sedimentary normal fault. The observed differences in fault development suggest that although multi-segment deltaic faults form single fault systems after segment linkage, individual pre-linkage characteristics can be preserved, supporting a possibly diverse upward growth and connection to younger faults in the overburden. The geological interpretations presented highlight the influence of large deep-rooted structures on the development, location and geometry of shallow deltaic faults, documenting the influence of an older structural grain on delta tectonics. 相似文献
12.
We use three-dimensional (3D) seismic reflection data to analyse the structural style and growth of a normal fault array located at the present-day shelf-edge break and into the deepwater province of the Otway Basin, southern Australia. The Otway Basin is a Late Jurassic to Cenozoic, rift-to-passive margin basin. The seismic reflection data images a NW-SE (128–308) striking, normal fault array, located within Upper Cretaceous clastic sediments and which consists of ten fault segments. The fault array contains two hard-linked fault assemblages, separated by only 2 km in the dip direction. The gravity-driven, down-dip fault assemblage is entirely contained within the 3D seismic survey, is located over a basement plateau and displays growth commencing and terminating during the Campanian-Maastrichtian, with up to 1.45 km of accumulated throw (vertical displacement). The up-dip normal fault assemblage penetrates deeper than the base of the seismic survey, but is interpreted to be partially linked along strike at depth to major basement-involved normal faults that can be observed on regional 2D seismic lines. This fault assemblage displays growth initiating in the Turonian-Santonian and has accumulated up to 1.74 km of throw.Our detailed analysis of the 3D seismic data constraints post-Cenomanian fault growth of both fault assemblages into four evolutionary stages: [1] Turonian-Santonian basement reactivation during crustal extension between Australia and Antarctica. This either caused the upward propagation of basement-involved normal faults or the nucleation of a vertically isolated normal fault array in shallow cover sediments directly above the reactivated basement-involved faults; [2] continued Campanian-Maastrichtian crustal extension and sediment loading eventually created gravitational instability on the basement plateau, nucleating a second, vertically isolated normal fault array in the cover sediments; [3] eventual hard-linkage of fault segments in both fault arrays to form two along-strike, NW-SE striking fault assemblages, and; [4] termination of fault growth in the latest Maastrichtian. We document high variability of throw along-strike and down-dip for both fault assemblages, thereby providing evidence for lateral and vertical segment linkage. Our results highlight the complexities involved in the growth of both gravity-driven normal fault arrays (such as those present in the Niger Delta and Gulf of Mexico) and basement-linked normal fault arrays (such as those present in the North Sea and Suez Rift) with the interaction of an underlying and reactivating basement framework. This study provides an excellent example of spatial variability in growth of two normal fault assemblages over relatively short spatial scales (∼2 km separation down-dip). 相似文献
13.
琼东南盆地2号断裂东带发育特征及形成机理 总被引：7，自引：3，他引：4
本文通过2号断裂陵水带、松南带基本结构及特征分析了它自新生代以来特别是古近纪的活动史和构造-沉积发育史。并发现,2号断裂松南带发育比陵水带更加复杂的结构样式,在此基础上,结合该断裂带的深部切片和地震资料,运用断层传播连接热点理论剖析了这种结构的成因,认为2号断裂松南带以L1023测线为界在成因上存在较大差异,这种差异是由早期断陷和所控充填方式都不同的两条断裂交叉连接而成,而且指出了这种成因断裂在油气勘探中应该注意的问题和意义。 相似文献
14.
Fault-Growth Pattern of the South Margin Normal Fault of the Yuguang Basin in Northwest Beijing and its Influencing Factors 总被引：4，自引：0，他引：4
Based on high-resolution remote sensing image interpretation, digital elevation model 3-D analysis, field geologic field investigation, trenching engineering, and ground-penetrating radar, synthetic research on the evolution of the Yuguang Basin South Margin Fault (YBSMF) in northwest Beijing was carried out. We found that the propagation and growth of faults most often occurred often at two locations: the fault overlapping zone and the uneven or rough fault segment. Through detailed observation and analysis of all cropouts of faults along the YBSMF from zone a to zone i, we identified three major factors that dominate or affect fault propagation and growth. First, the irregularity of fault geometry determine the propagation and growth of the fault, and therefore, the faults always propagate and grow at such irregular fault segments. The fault finally cuts off and eliminates its irregularity, making the fault geometry and fault plane smoother than before, which contributes to the slipping movement of the half-graben block in the basin. Second, the scale of the irregularity of the fault geometry affects the result of fault propagation and growth, that is, the degree of the cutting off of fault irregularity. The degree of cutting off decreases as irregularity scale increases. Third, the maximum possible slip displacement of the fault segment influences the duration of fault propagation and growth. The duration at the central segments with a large slip displacement is longer than that at the end segments with a smaller slippage value. 相似文献
15.
Several strike–slip faults at Crackington Haven, UK show evidence of right-lateral movement with tip cracks and dilatational jogs, which have been reactivated by left-lateral strike–slip movement. Evidence for reactivation includes two slickenside striae on a single fault surface, two groups of tip cracks with different orientations and very low displacement gradients or negative (left-lateral) displacements at fault tips.
Evidence for the relative age of the two strike–slip movements is (1) the first formed tip cracks associated with right-lateral slip are deformed, whereas the tip cracks formed during left-lateral slip show no deformation; (2) some of the tip cracks associated with right-lateral movement show left-lateral reactivation; and (3) left-lateral displacement is commonly recorded at the tips of dominantly right-lateral faults.
The orientation of the tip cracks to the main fault is 30–70° clockwise for right-lateral slip, and 20–40° counter-clockwise for left-lateral slip. The structure formed by this process of strike–slip reactivation is termed a “tree structure” because it is similar to a tree with branches. The angular difference between these two groups of tip cracks could be interpreted as due to different stress distribution (e.g., transtensional/transpressional, near-field or far-field stress), different fracture modes or fractures utilizing pre-existing planes of weakness.
Most of the d–x profiles have similar patterns, which show low or negative displacement at the segment fault tips. Although the d–x profiles are complicated by fault segments and reactivation, they provide clear evidence for reactivation. Profiles that experienced two opposite slip movements show various shapes depending on the amount of displacement and the slip sequence. For a larger slip followed by a smaller slip with opposite sense, the profile would be expected to record very low or reverse displacement at fault tips due to late-stage tip propagation. Whereas for a smaller slip followed by larger slip with opposite sense, the d–x profile would be flatter with no reverse displacement at the tips. Reactivation also decreases the ratio of dmax/L since for an original right-lateral fault, left lateral reactivation will reduce the net displacement (dmax) along a fault and increase the fault length (L).
Finally we compare Crackington Haven faults with these in the Atacama system of northern Chile. The Salar Grande Fault (SGF) formed as a left-lateral fault with large displacement in its central region. Later right-lateral reactivation is preserved at the fault tips and at the smaller sub-parallel Cerro Chuculay Fault. These faults resemble those seen at Crackington Haven. 相似文献
16.
基于实验结果讨论断层破裂与强震物理过程的若干问题 总被引：9，自引：0，他引：9
基于断层摩擦滑动实验、含凹凸体断层的变形破坏实验、断层撕裂扩展的实验、交叉断层的变形实验等多种实验结果并结合前人的工作 ,讨论了与断层破裂与强震物理过程相关的若干问题。研究表明 ,断层的整体滑动引起其两侧块体弹性应变的释放 ,是强震发生的原因 ,因此构造活动区具有较大尺度、结构连续且简单、介质均匀的断层 (或断层段 )是产生强震必备的构造条件 ,深部新生断层(盲断层 )向上撕裂扩展产生强震 ,尚需“弱层”提供“解耦”条件以便断层发生整体滑动。强震孕育过程中包含着凹凸体的破裂 ,断层面上凹凸体的尺度、强度及数量决定着前震活动的特征、强震动态破裂过程以及前兆现象。由断层分割的块体通过边界断层的交替滑动、以“框动”的方式运动 ,因此块体周边的断层上强震活动具有交替性。 相似文献
17.
We investigate the structural style and evolution of a salt-influenced, extensional fault array in the Egersund Basin (Norwegian North Sea) through analysis of 3D reflection seismic and well data. Analysis of fault geometry/morphology, throw distribution and syn-kinematic strata reveal an intricate but systematic style of displacement and growth, suggesting an evolution of (1) initial syn-sedimentary fault growth contemporaneous with salt mobilization initiated during the Late Triassic, (2) cessation of fault activity and burial of the stagnant fault tips, and (3) subsequent nucleation of new faults in the cover above contemporaneous salt re-mobilization initiated during the Late Cretaceous, with downward propagation and linkage with faults. Stage 3 was apparently largely controlled by salt mobilization in response to basin inversion, as reactivated faults are located where the underlying salt is thick, while the non-reactivated faults are found where salt is depleted. Based on the 3D-throw analyses, we conclude that a combination of basement faulting and salt (re-) mobilization is the driving mechanisms behind fault activation and reactivation. Even though the sub- and supra-salt faults are mainly geometrically decoupled through the salt, a kinematic coupling must have existed as sub-salt faults still affected nucleation and localization of the cover faults. 相似文献
18.
断层封闭性影响因素及类型划分 总被引：24，自引：0，他引：24
影响断层封闭性的因素很多，但归结起来主要有3个，即断距、断裂充填性质和断面的紧闭程度。断距影响着断层两盘砂泥岩层的对置状态，断裂充填性质决定了断层的垂向和侧向封闭性，断面的紧闭程度决定了断层的垂向封闭能力。考虑断层在油气运移聚集过程中的作用，将断层封闭性分为侧向封闭性和垂向封闭性两大类，再根据断层在侧向和垂向的封闭程度，将断层封闭性分为完全封闭、部分开启、部分封闭和完全开启4个亚类。 相似文献
19.
A high-quality 3D seismic volume from offshore Espírito Santo Basin (SE Brazil) is used to assess the importance of gravitational collapse to the formation of crestal faults above salt structures. A crestal fault system is imaged in detail using seismic attributes such as curvature and variance, which are later complemented by analyses of throw vs. distance (T-D) and throw vs. depth (T-Z). In the study area, crestal faults comprise closely spaced arrays and are bounded by large listric faults, herein called border faults. Two episodes of growth are identified in two opposite-dipping fault families separated by a transverse accommodation zone. Statistical analyses for eighty-four (84) faults show that fault spacing is < 250 m, with border faults showing the larger throw values. Fault throw varies between 8 ms and 80 ms two-way time for crestal faults, and 60–80 ms two-way time for border faults. Fault length varies between ∼410 m and 1750 m, with border faults ranging from 1250 m to 1750 m. This work shows that border faults accommodated most of the strain associated with salt growth and collapse. The growth history of crestal faults favours an isolated fault propagation model with fault segment linkage being associated with the lateral propagation of discrete fault segments. Importantly, two episodes of fault growth are identified as synchronous to two phases of seafloor erosion, rendering local unconformities as competent markers of fault reactivation at a local scale. This paper has crucial implications for the understanding of fault growth as a means to assess drilling risk and oil and gas migration on continental margins. As a corollary, this work demonstrates that: 1) a certain degree of spatial organisation occurs in crestal fault systems; 2) transverse accommodation zones can form regions in which fault propagation is enhanced and regional dips of faults change in 4D. 相似文献
20.
本文研究了位于鄂皖边境的郯-庐断裂带南段尾端地区的构造变形特征,通过野外实际工作,结合地球物理、遥感资料的分析与应用,对这条巨大平移断裂尾端的变形情况进行了初步的探讨,提出四种位移调整模式,并通过实验研究来认识平移断裂尾端的应力分布状态,以及应力与应变的相互关系。文中还就郯-庐断裂带的南延问题提出了讨论。 相似文献