共查询到19条相似文献，搜索用时 171 毫秒
1.
库车前陆褶皱-冲断带前缘盐构造分段差异变形特征 总被引：12，自引：5，他引：7
库车前陆褶皱-冲断带前缘秋里塔格构造带发育大量盐构造,其类型丰富多样。根据野外露头、钻井和地震资料识别出的盐构造样式主要有盐推覆、盐枕、盐墙、盐焊接、鱼尾构造、盐撤凹陷、突发构造、断层传播褶皱、断层转折褶皱和三角带构造等。秋里塔格构造带盐构造变形表现出明显的分段差异变形特征,其中西段却勒地区以古隆起(盐下)—盐枕(盐层)—逆冲推覆构造(盐上)为主;中段西秋地区以构造斜坡(盐下)—盐墙(盐层)—断层传播褶皱、向斜(盐上)为主;东段东秋地区则以断层转折褶皱(盐下)—盐推覆(盐层)—断层传播褶皱(盐上)为主。造成这种盐构造分段差异变形的主要控制因素包括基底断裂、含盐层系、构造转换带和变形空间等方面的差异性,其中基底构造和含盐层系的差异性起主导作用。 相似文献
2.
塔里木盆地库车前陆褶皱带中段盐相关构造特征与油气聚集 总被引：24，自引：2，他引：24
塔里木盆地北部库车前陆褶皱带古新统一始新统发育盐岩层系，将库车前陆褶皱带构造变形和圈闭样式分为三层，即盐上构造、盐层(盐间)构造和盐下构造。盐上构造包括盐上背斜、盐上逆冲断层及断层相关褶皱、盐上背冲断块构造、强制褶皱、盐上逆冲断层遮挡构造和盐推覆构造等；盐层(盐间)构造主要包括盐枕构造、盐间断褶构造、盐焊接构造和外来盐席等；盐下构造主要有背冲断块构造、断层相关褶皱、叠瓦冲断带和双重构造等。库车前陆褶皱带盐构造的形成可能受挤压作用、重力滑动和重力扩展作用多重控制。笔者等讨论了盐相关构造油气成藏条件和模式，认为库车前陆褶皱带盐岩层变形与丰富的圈闭构造形成密切相关，烃源岩主要位于盐下，盐岩层作为优质盖层构成石油和天然气藏最优越的遮挡条件，断裂对盐下、盐间和盐上油气成藏都起重要控制作用，但盐下是最有利的油气聚集场所。 相似文献
3.
古近系库姆格列木组和新近系吉迪克组膏盐层构成了库车前陆褶皱冲断带的区域滑脱层。在褶皱冲断带前缘,膏盐层发生塑性流动,其内部形成多种构造样式。根据野外考察、地震剖面解释和钻井资料识别出的膏盐层内部构造变形样式主要包括盐枕、盐墙、盐推覆、鱼尾构造、盐焊接(断层焊接)、盐缩颈、透镜状增厚和盐垛等盐构造。盐构造在形成时间上具有一定的演化序列,库车前陆褶皱冲断带总体表现为由北向南迁移,前缘秋里塔格构造带则是从西往东迁移,盐推覆、盐焊接、盐枕等构造形成时间较早,盐墙形成较晚,东秋地区的盐构造形成时间整体较西段和中段晚,规模也较小。 相似文献
4.
库车褶皱冲断带前缘盐层厚度对滑脱褶皱构造特征及演化的影响 总被引：1，自引：0，他引：1
库车褶皱冲断带前缘发育一系列滑脱褶皱,虽然卷入变形的新生代地层及底部滑脱层(古近系盐层)相同,但滑脱褶皱的构造特征及演化存在显著差异。文中结合野外地质调查结果以及钻井资料和高品质二维地震反射剖面解析,以南喀背斜和米斯坎塔克背斜为例,估算出盐层初始厚度,并讨论其对于滑脱褶皱样式及其演化过程的影响。结果表明,南喀背斜和米斯坎塔克背斜下伏盐层初始厚度不同,估算出前者厚度介于0.1~0.5 km,主要为0.1~0.3 km,而后者却大约为1.0 km。与此同时,南喀背斜和米斯坎塔克背斜均表现出分段差异变形特征。南喀背斜为低缓的滑脱褶皱,其东段隐伏地下,变形方式为褶皱作用;而西段出露地表,背斜核部发育隐伏的逆冲断层,变形方式为褶皱作用和断层作用。背斜西段平均隆升速率大于东段,导致西段隆升出露地表。米斯坎塔克背斜表现为大规模滑脱褶皱,根据变形特征的不同可以分为3段,东段背斜倾向北,盐岩在其核部及北翼下方聚集加厚;而中-西段背斜倾向南,其中中段背斜核部位置盐岩聚集加厚,两翼下伏盐岩减薄甚至形成盐焊接。而在西段背斜呈箱状,两翼下方盐岩厚度至少为1.0 km。笔者总结出库车褶皱冲断带前缘发育的7种滑脱褶皱变形样式,通过构造分析得出,研究区滑脱褶皱的变形主要受盐层厚度、构造缩短量及盐岩流动变形共同控制,其中盐层厚度起主导作用,控制了滑脱褶皱的发育位置,并影响了滑脱褶皱的变形样式。研究结果将为其他褶皱冲断带中滑脱褶皱的相关研究提供重要参考,特别是在缺少高品质地震资料,或者构造变形强烈、地震资料品质较差的地区。 相似文献
5.
秋里塔格构造带位于库车褶皱冲断前缘,其东段包括东秋里塔格背斜和库车塔吾背斜。野外调查和地震剖面解释表明:秋里塔格构造带东段盐下发育断层转折褶皱; 盐上东秋里塔格背斜为滑脱箱状背斜,库车塔吾背斜核部为南倾逆冲断层所破坏。演化剖面显示秋里塔格构造带东段在侏罗纪断陷期发育了正断裂,其后为平静期,直到库车晚期后逆冲断层和褶皱快速发育,背斜最终形成。膏盐岩及古构造对构造变形具有重要影响,一方面作为滑脱层,分割了盐下层与盐上层,导致二者形成不同的构造样式; 另一方面塑性流动充填于背斜核部。由于膏盐岩的厚度差异,东秋里塔格背斜盐上发育褶皱,而库车塔吾背斜核部被逆冲断层破坏,膏盐层厚度还影响了膏盐层上下构造高点的相对位置。盐下构造的发育受侏罗纪古构造控制,进而影响了盐上构造的发育。 相似文献
6.
褶皱相关断层——以库车坳陷新生界盐上构造层为例 总被引：8，自引：3，他引：5
以盐构造解析的方法,综合地震与地质资料,表明库车坳陷新生界中的盐上断层受控于褶皱作用。盐上地层首先发生褶皱变形,随着褶皱作用的加强,然后发生断裂作用,盐上构造层的变形方式为褶皱相关断层,其变形特征不同于断层相关褶皱。从断层成因机制可见:断层相关褶皱理论不适用于库车新生代坳陷盐构造发育区。库车坳陷膏盐层的发育造成盐上构造层与盐下构造层变形有差异,盐上构造层以褶皱作用为主,盐下构造层以冲断作用为主。库车坳陷盐上构造层主要为褶皱相关断层,发育张性断块、后翼突破断层、前翼突破断层及褶皱相关断层组合等构造样式,根据盐上构造层的变形特征总结了褶皱相关断层的演化。 相似文献
7.
天山南麓库车坳陷西部沉积古近系膏盐岩,盐层下伏中生界发现万亿立方米储量天然气田,是我国西气东输重要气源。库车坳陷盐下是油气勘探关注目标,目前研究认识不能满足勘探需求,尤其是盐构造形成机制存在争议,盐构造平衡恢复是研究难点。本文应用二维构造平衡剖面技术,综合地震剖面、钻井和地表地质资料,选取库车坳陷西段四条剖面,通过StructureSolver公司开发的构造恢复软件(简称SS),开展平衡恢复工作,分层恢复盐上层、膏盐层、盐下层,复原挤压变形前地震剖面。研究结果揭示库车坳陷西段发育二期盐构造:渐新世-中新世发育刺穿型盐丘,上新世-第四纪发育挤压型盐构造。挤压作用下早期盐丘演变为盐席、盐墙,盐上层发育盐逆冲断层和盐背斜,盐下发育叠瓦状逆冲断层和挤压构造楔。库车坳陷西段盐层上覆冲积扇沉积(重力)差异负载是发育盐丘的原因,盐丘分布于山前冲积扇前端和却勒冲积扇南侧。库车坳陷盐下发育逆冲构造楔,应用临界楔理论研究构造楔顶面坡度与底部滑脱层角度变化,盐下构造楔顶面坡度突变,指示底部滑脱层角度发生变化,推断古生代基底正断层卷入逆冲构造楔。 相似文献
8.
膏盐层在库车秋里塔格构造带构造变形及成藏中的作用 总被引：6，自引：4，他引：2
库车坳陷秋里塔格构造带发育古近系库姆格列木群和新近系吉迪克组两套膏盐层,这两套膏盐层对该区构造变形和油气成藏起了重要的作用。地震剖面揭示盐层的存在使得秋里塔格构造带构造上、下分层,盐上层主要形成盐推覆构造、逆冲断层、断层传播褶皱和盐核背斜等构造;膏盐层主要形成盐枕、盐焊接或断层焊接等构造;盐下层主要发生断层转折褶皱、背冲断块和逆冲断层等变形。膏盐层组成了该区主要的盖层,并与盐下储层组成了优质的储盖组合,对盐下油气藏的保存极为有利。膏盐层可以改善盐下储层的储集性能,而且膏盐层的塑性流动还可以吸收盐下构造应力,使得盐下构造圈闭在强烈的构造挤压中得以保存。 相似文献
9.
前陆褶皱冲断带厚皮缩短盐构造运动的物理模拟 总被引：8，自引：0，他引：8
尺度物理实验用干石英砂和聚合硅树脂为实验材料,模拟了前陆褶皱冲断带厚皮缩短盐构造,并与薄皮缩短盐构造及无盐层的褶皱冲断带构造模型进行了对比。实验表明,由于塑性盐层的存在,厚皮缩短盐构造呈3层式结构模式。盐上层主要形成敞开褶皱、箱状褶皱、前冲和背冲断层以及冲垒构造,盐下层形成逆冲断层及冲垒构造,断层通常都终止于盐层中。尽管盐层局部变薄或增厚,但不形成刺穿型盐构造。褶皱冲断带不具构造指向特征,其楔形库仑锥剖面呈平台与斜坡两段式形态。模型对比表明,厚皮缩短与薄皮缩短所产生的盐上层构造形态相似,不易区分;但二者的库仑锥剖面有所不同。厚皮前陆褶皱冲断盐构造与无盐层的褶皱冲断构造无论是其几何形态、还是库仑锥剖面都有极大的差别,极易区分：实验结果对解释前陆褶皱冲断构造和寻找盐下油气圈闭都有着重要的指导意义。 相似文献
10.
库车坳陷西段新生代盐构造特征及演化 总被引：7，自引：1，他引：6
库车坳陷古-始新世沉积厚层膏盐岩,在沉积差异形成的重力负载作用下,膏盐岩发生塑性流动,山前的膏盐岩流向盆地内侧,发育盐底辟构造,形成吐孜玛扎盐墙、却勒盐丘,膏盐岩的塑性流动发生在膏盐层沉积后不久,并且持续到上新世库车早期,盐底辟构造主要通过被动底辟作用完成。上新世晚期,库车坳陷受到强烈的挤压作用,发生大规模的逆冲推覆,吐孜玛扎盐墙、却勒盐丘(应变强度薄弱部位)的北侧发育断层,盐岩沿断层刺穿地表,形成底辟型盐墙和喷出型盐席,同时发育整合型米斯坎塔克盐背斜和大宛齐盐枕。库车坳陷的盐构造分为两个阶段:构造平静期(渐新世-上新世),以重力差异负载作用为主,发育底辟型盐构造;构造挤压期(上新世晚期-现今),挤压作用强烈,形成逆冲推覆断层,在不同的构造部位分别形成盐席、盐墙、盐背斜,早期的盐构造对于后续挤压作用下盐构造的形成和演化具有重要的控制作用。 相似文献
11.
库车坳陷却勒地区新生代盐构造特征、演化及变形控制因素 总被引：3，自引：0，他引：3
本文利用野外地质调查结果、遥感资料、地震资料和钻、测井数据,建立了两条库车坳陷却勒地区的区域大剖面,约束却勒地区盐构造特征和演化,分析东、西段变形差异及差异形成过程,探讨构造变形控制因素。却勒地区发育的盐构造样式主要有盐底辟、盐焊接、盐撤凹陷、大型盐推覆体、外来盐席、盐枕、盐背斜和滑脱褶皱,其中,盐撤凹陷、盐背斜和滑脱褶皱仅发育于东段,造成东、西段构造变形差异。却勒地区盐构造分为3期:①渐新世—中新世吉迪克期为构造平静期,发育盐撤凹陷和盐底辟;②中新世康村期—上新世早期构造挤压微弱,发生早期褶皱作用,却勒盐丘继续发育,北部盐底辟中新世末停止发育;③上新世晚期—现今发生大规模逆冲推覆,是褶皱-冲断带主要形成时期,发育大型盐撤凹陷、外来盐席、盐推覆构造、盐背斜和滑脱褶皱。却勒地区东、西段盐构造变形差异主要形成于上新世晚期—现今(第3期)。喀拉玉尔滚右旋走滑断层为薄皮构造,调节了却勒地区东、西段前缘的变形差异。却勒地区构造变形主要受控于盐岩沉积范围、区域构造应力及强度、上覆层应变强度和差异负载(沉积负载和局部构造负载)。 相似文献
12.
Salt tectonic along offshore North Sinai was studied using seismic reflection data. The study revealed and identified various types of salt tectonics and structures in the study area. The triggering mechanism of salt tectonics was attributed to the pressure regime initiated from overloading sediments on the Messinian evaporites. The sediment load of 3,000?m exceeds the critical load (more than 1,000?m) and hence creates a pressure zone. The salt-generated structures resulted from thin-skinned extension that is driven by gravity gliding of the overloading sediments above the Messinian evaporite boundary, which acts as a detachment layer. These structures comprise normal growth faults and keystone grabens, trending roughly perpendicular to the slope of the continental margin. Salt tectonics in the study area were also triggered by the deformation of the movement of evaporite layer that causes stretching and fragmentation of the evaporite layer. Moving salt layer took place laterally and vertically, causing lateral and vertical pressures inside the Pliocene sediments. These movements of sediments led to the formation of salt rollers, salt weld, salt diapirs, rollover structures, and fault blocks. The interpretation of seismic data illustrates that the evaporite layer was switched off between the famous reflector M at its top and another reflector N at its base. M reflector is present and can be traced across the whole study area, while the N reflector pinched out in some parts of the study area. 相似文献
13.
Amara Masrouhi Olivier Bellier Hemin Koyi 《International Journal of Earth Sciences》2014,103(3):881-900
Detailed geologic mapping, structural analysis, field cross-sections, new dating based on planktonic foraminifera, in addition to gravity signature of Lorbeus diapir, are used to characterize polyphase salt diapirism. This study highlights the role of inherited faulting, which controls and influences the piercement efficiency and the style and geometry of the diapir; and also the localization of evaporite early ascent displaying diapiric growth during extension. Salt was extruded along the graben axis developed within extensional regional early Cretaceous tectonic associated with the North African passive margin evolution. Geologic data highlight reactive diapirism during Albian time (most extreme extension period) and passive diapirism during the late Cretaceous post-rift stage. Northeastern Maghreb salt province gives evidences that contractional deformations are not associated with significant diapirism. During shortening, the initial major graben deforms as complex anticlines where diapirs are squeezed and pinched from their feeding. 相似文献
14.
Gabor Tari Rudi Dellmour Emma Rodgers Chloe Asmar Peter Hagedorn Adel Salman 《Arabian Journal of Geosciences》2016,9(10):570
A variety of distinct salt tectonic features are present in the Sab’atayn Basin of western Yemen. Based on the interpretation of regional 2D seismic reflection data and exploration wells in the central part of the basin, an Upper Jurassic evaporite formation produced numerous salt rollers, salt pillows, reactive, flip-flop, and falling diapirs. Due to regional extension, halokinetics began as soon as the early Cretaceous, within just a few million years after the deposition of the Tithonian Sab’atayn evaporite sequence, by formation of salt rollers. The salt locally formed salt pillows which evolved to reactive and active salt diapirs and diapiric salt walls as the result of renewed, but low-strain extension in the basin. Some of the diapiric walls further evolved into falling diapirs due to ongoing extension. As the result of a prominent extensional episode at the end of the Cretaceous, many of the diapiric walls in the basin are controlled by large normal faults on their updip flanks. As the post-Cretaceous sedimentary cover is largely missing in the study area, the assumed reactivation of salt structures during the Cenozoic remains poorly constrained. The interpreted changes in the style of salt tectonics in the Sab’atayn Basin offer a better understanding of the regional-scale tectonic development of the Arabian plate during the late Jurassic and Cretaceous. 相似文献
15.
东营凹陷盐底辟作用与中央隆起带断裂构造成因 总被引：23，自引：10，他引：13
华北渤海湾盆地济阳坳陷的东营凹陷中央隆起带同生断层非常发育,断层数量较多。主干正断层的下降盘上形成“逆牵引”构造,组成“负花状”地堑断裂系。这些断裂系将中央隆起带分割为一系列小断块。本文将这些断裂系和相关的小断块划分为3个构造,分别称为辛镇、东营和郝家—现河庄(简称郝—现)构造。研究证明,复杂断裂与断块组合构造主要为盐底辟作用的结果,伴生的逆牵引作用形成“包心状”的复杂断裂构造形态,总体上,东营凹陷中央隆起带构造成因是区域北北西—南南东向伸展作用下局部底辟作用和逆牵引作用共同形成的,而不是走滑成因。据强度,底辟构造可分为低幅度隆起和隐刺穿构造。其形成时期主要为沙河街组三段沉积期开始持续到馆陶组沉积前。底辟物质由盐岩为主的塑性层组成。 相似文献
16.
南天山库车褶皱-冲断带喀拉玉尔滚构造带新生代变形特征及其控制因素 总被引：1，自引：0，他引：1
喀拉玉尔滚构造带是南天山库车褶皱-冲断带的变形前缘, 其地下深层变形特征仍然不清楚.结合野外地质调查结果、数字高程模型数据、钻井数据和高品质二维地震反射剖面, 厘定喀拉玉尔滚构造带背斜的平面展布、几何学和运动学特征及变形时间, 并结合前人研究成果探讨喀拉玉尔滚构造带新生代变形控制因素.喀拉玉尔滚构造带为典型的挤压构造带, 近EW向延伸约165km, 由一系列带状背斜组成, 且背斜核部发育多条隐伏逆冲断层.喀拉玉尔滚构造带新生代变形特征主要表现为5个方面: (1)北喀背斜为盐枕构造; (2)中喀背斜和南喀背斜的几何形态不对称、背斜倾伏方向相反, 分别为向北和向南, 二者交汇处发生了位移转换; (3)羊塔克背斜和英买力背斜为基本对称的低幅度滑脱褶皱; (4)背斜幅度整体上从西往东逐渐降低; (5)背斜变形时间从西往东逐渐变新.研究结果表明, 喀拉玉尔滚构造带新生代变形主要受区域挤压作用、盐层和基底构造共同控制. 相似文献
17.
Christian Brandes Carolin Schmidt David Colin Tanner Jutta Winsemann 《International Journal of Earth Sciences》2013,102(8):2239-2254
Analysing the paleostress field in sedimentary basins is important for understanding tectonic processes and the planning of drilling campaigns. The Subhercynian Basin of northern Germany is a perfect natural laboratory to study the paleostress field in a developing foreland basin. The simple layer-cake geometry of the basin-fill is dominated by several piercing and non-piercing salt structures. We derived the paleostress field from the orientation of fracture sets, faults, slickensides and stylolites. On a regional scale, the basin-fill is characterized by a horizontal compressional paleostress vector that is mainly NNE-SSW-oriented, which reflects the Late Cretaceous inversion phase in Central Europe. We show that the local paleostress field is distinctly perturbated due to the salt structures. Along the edge of the salt pillows, the maximum horizontal paleostress vector is deflected by up to 90° from the regional trend. In the case of the Elm salt pillow, it forms a radial pattern. Restoration of balanced cross-sections demonstrates at least 9 % of the shortening of the north-western part of the Subhercynian Basin was achieved by folding. The salt structures in the north-western Subhercynian Basin are the result of varying stress conditions. Initial extension in the Triassic caused first salt movements that prevailed during the Jurassic and Early Cretaceous. Most important is the Late Cretaceous contractional phase that shortened the diapirs and led to the formation of the salt pillows between diapirs due to detachment folding. We derive four main controlling factors for such salt-dominated contractional basins: (1) the wedge-shape basin-fill is the product of the dynamic load at the southern margin of the basin, (2) a basal salt layer fed the diapirs and acted as a detachment horizon during the later shortening, (3) detachment folding was the dominating deformation mechanism during contraction, and (4) the pre-existing diapirs controlled the position of the detachment folds. 相似文献
18.
滇西兰坪中新生代盆地广泛发育盐岩层系。通过对金顶超大型铅锌矿区的露天采厂和地下采坑的最新野外调查及大量钻孔资料的综合分析,研究区盐岩层系具有多期、多阶段运动的特点,厚度分布极不均一,它们作为区域推覆构造作用的滑脱层,对盐上层构造变形起着重要控制作用,形成一系列储矿构造。研究表明,矿区盐构造主要包括盐枕、盐背斜、盐焊接、盐穿刺、盐推覆、盐岩滑脱-断层相关褶皱组合等多种盐构造变形样式。这些盐构造的形成演化及变形机制主要受到推覆挤压缩短作用、基底断层作用和塑性流动汇聚作用、盐下和盐上层断裂滑脱作用等控制,主要沿推覆断裂构造带呈串珠状分布。金项矿区盐构造分为两个阶段:古新世–始新世挤压–拗陷层内变形阶段,形成盐枕、隆升较低的盐背斜等整合型盐构造;渐新世的逆冲推覆–盐岩滑脱阶段,受强烈的挤压推覆作用而形成盐墙、盐株等盐穿刺型构造。盐构造不同阶段的变形演化对金属元素富集成矿起到关键作用,其流动变形而形成的盐构造圈闭促使了金属聚集成矿。 相似文献
19.
The NW–SE-striking Northeast German Basin (NEGB) forms part of the Southern Permian Basin and contains up to 8 km of Permian to Cenozoic deposits. During its polyphase evolution, mobilization of the Zechstein salt layer resulted in a complex structural configuration with thin-skinned deformation in the basin and thick-skinned deformation at the basin margins. We investigated the role of salt as a decoupling horizon between its substratum and its cover during the Mesozoic deformation by integration of 3D structural modelling, backstripping and seismic interpretation. Our results suggest that periods of Mesozoic salt movement correlate temporally with changes of the regional stress field structures. Post-depositional salt mobilisation was weakest in the area of highest initial salt thickness and thickest overburden. This also indicates that regional tectonics is responsible for the initiation of salt movements rather than stratigraphic density inversion.Salt movement mainly took place in post-Muschelkalk times. The onset of salt diapirism with the formation of N–S-oriented rim synclines in Late Triassic was synchronous with the development of the NNE–SSW-striking Rheinsberg Trough due to regional E–W extension. In the Middle and Late Jurassic, uplift affected the northern part of the basin and may have induced south-directed gravity gliding in the salt layer. In the southern part, deposition continued in the Early Cretaceous. However, rotation of salt rim synclines axes to NW–SE as well as accelerated rim syncline subsidence near the NW–SE-striking Gardelegen Fault at the southern basin margin indicates a change from E–W extension to a tectonic regime favoring the activation of NW–SE-oriented structural elements. During the Late Cretaceous–Earliest Cenozoic, diapirism was associated with regional N–S compression and progressed further north and west. The Mesozoic interval was folded with the formation of WNW-trending salt-cored anticlines parallel to inversion structures and to differentially uplifted blocks. Late Cretaceous–Early Cenozoic compression caused partial inversion of older rim synclines and reverse reactivation of some Late Triassic to Jurassic normal faults in the salt cover. Subsequent uplift and erosion affected the pre-Cenozoic layers in the entire basin. In the Cenozoic, a last phase of salt tectonic deformation was associated with regional subsidence of the basin. Diapirism of the maturest pre-Cenozoic salt structures continued with some Cenozoic rim synclines overstepping older structures. The difference between the structural wavelength of the tighter folded Mesozoic interval and the wider Cenozoic structures indicates different tectonic regimes in Late Cretaceous and Cenozoic.We suggest that horizontal strain propagation in the brittle salt cover was accommodated by viscous flow in the decoupling salt layer and thus salt motion passively balanced Late Triassic extension as well as parts of Late Cretaceous–Early Tertiary compression. 相似文献