白云鄂博叠加褶皱及其变形机制   总被引：3，自引：0，他引：3  

张玉清  王弢  贾和义  尚恒胜 《华南地质与矿产》2003,(1):23-26

华北地块北缘中上元古界的白云鄂博群尖山组，在白云鄂博群东南花果山一带褶皱变形十分复杂，为了研究其褶皱形态、变形机制，在原1：5万填图的基础上选近1km^2的范围进行1：2000大比例尺地质填图，以变质长石石英砂岩为标志层，确定了两期褶皱构造。综合区域资料表明：早期EW向褶皱以纯剪切、纯剪切＋简单剪切为主，是加里东运动的结果；晚期褶皱表现为EW向压扁，为印支运动所形成。  相似文献   

Inversion tectonics, interference pattern and extensional fault-related folding in the Eastern Anti-Atlas, Morocco     

Charles Robert-Charrue  Martin Burkhard 《Swiss Journal of Geoscience》2008,101(2):397-408

  相似文献   

A general statistical test for the effect of folding     

Nicholas I. Fisher  Peter Hall 《Geophysical Journal International》1991,105(2):419-427

  相似文献   

平衡剖面技术中Suppe模型的求解及应用   总被引：1，自引：0，他引：1  

何维刚  王权锋  孙继军  周思华 《物探化探计算技术》2005,27(4):348-350

平衡剖面技术是根据几何守恒原理所确立的地质剖面正、反演方法,它是构造变形恢复的重要手段。通过对Suppe模型的求解讨论,给出了其数值解的实现方法,并给出了应用实例。  相似文献   

天山北麓活动构造基本特征   总被引：21，自引：2，他引：19  

汪一鹏  沈军 《新疆地质》2000,18(3):203-210

在近ＳＮ向强烈挤压下,天山北麓发育了两个不同类型的大型逆冲推覆构造,一是乌鲁木齐以西具有典型断裂扩展褶皱特征的依连哈比尔尕山山前推覆构造,二是乌鲁木齐以东博格达山前弧形推覆构造;同时水平剪切作用成了大型斜切天山的右旋走滑断裂。ＮＷ－ＮＮＷ向的博罗科努一阿齐克库都克断裂切割天山,右旋走滑特征非常清楚。天山北麓的应变分配特征在内陆造山带中具有典型性。  相似文献   

壳内熔融与大陆造山——中山大学地质学系成立90周年暨陈国达院士诞辰102周年纪念   总被引：1，自引：0，他引：1  

陈国能  陈震  陈雄  丁汝鑫  彭卓伦  RodneyGrapes  张珂  王岳军  娄峰  沈文杰  郑义  张俊浩  邱惟  许清燕  王勇 《大地构造与成矿学》2015,(3)

本文将造山作用分为地槽褶皱造山和地台(克拉通)活化造山两种类型,并认为两者均起因于板块的汇聚过程。地槽造山是洋壳向陆壳的转换过程,其标志是地槽沉积物初次熔融形成的、以TTG为主的"不成熟花岗岩"产生。板块俯冲过程的能量转换,导致大陆岩石圈内能升高,包括TTG在内的基底地槽构造层的再次熔融(重熔),产生再生或重熔岩浆形成活化造山期的"成熟花岗岩";壳内重熔岩浆层形成和增厚最终导致大陆克拉通发生大规模压缩变形(活化造山)。造山作用的多幕性和花岗岩活动多期性,以及上老下新的花岗岩"层序",被认为主要与板块俯冲过程的能量转换速度有关。  相似文献   

A 1.5D model of the steady-state thermal structure of detachment folds     

《Marine and Petroleum Geology》2014

We present a 1.5D steady-state model of thermal perturbations in the core of detachment anticlines. The model incorporates the effects of heat conduction, advection by folding, radiogenic sources, and conversion of work into heat by viscous dissipation. We work out analytical solutions of model's equations for heat flow and temperature field for the case of low amplitude detachment folds growing in a thick homogeneous stratigraphy.Our analytical solutions for the simplest case of no heat sources show that detachment folds develop a thermal boundary layer. Conduction of heat dominates inside the layer, whereas advection of heat by folding prevails outside the boundary layer. We also find that heat flow in a growing detachment fold decays exponentially with the square of the thickness of the detached stratigraphic section. When heat sources are included into the problem we find that radiogenic heat generates thermal anomalies at the crest of the anticlines whereas viscous dissipation produces thermal anomalies at the core of the detachment fold.We analyze three cases of geological interest: detachment folds growing in evaporitic sequences, marine carbonates, and shaley sediments. For a typical uplift rate of 2 mm/yr conduction dominates in the first class of rocks. Viscous dissipation dominates in folds growing in limestone due to its high viscosity. Advection and the generation of heat by radiogenic isotopes dominate the growth of detachment folds in shale. Additionally, the cooling histories of Lagrangian particles embedded in the fold for the last two cases are analyzed. The core of the fold is characterized by rapid cooling whereas the limbs cool at slower rates than the core. Thus, the development of detachment anticlines may either accelerate maturation of source rocks and expand the maturation window or halt it by removing source rocks from the generating window.  相似文献   

The junction of the eastern Central Asian Fold Belt and the Siberian Platform: deep structure and Mesozoic tectonics and geodynamics     

B.F. Shevchenko  M.V. Goroshko  A.N. Didenko  V.A. Gur'yanov  V.S. Starosel'tsev  A.S. Sal'nikov 《Russian Geology and Geophysics》2011,52(12):1672-1679

The tectonic structure of the junction of the eastern Central Asian Fold Belt and the Siberian Platform, along with the deep structure of the Earth's crust and lithosphere in this region, has been described on the basis of new geological and geophysical data (seismic, geoelectric, and space-structural studies as well as new-generation geological maps), combined with new interpretation techniques (processing of the previous data by special software). The data suggest the existence of oblique collision during the convergence of the tectonic plates and, correspondingly, tectonic units composing these plates, when the Mongol–Okhotsk paleobasin closed. Such a scenario within the Aldan–Stanovoi Shield is evidenced by areas of syn- and postcollisional magmatism, with their deep-level and geochemical characteristics, and by the presence of a Late Mesozoic fold–thrust zone. Deep “traces” of these tectonomagmatic events, detected in the course of geological and geophysical modeling, are manifested in inclined deep boundaries between the crustal and lithospheric blocks. On the Earth's surface, they correspond to large fault systems: the Dzheltulak, North and South Tukuringra, Gulyui, and Stanovoi. It has been found that the influence of collision decreases northward with distance from the junction of the eastern Central Asian Fold Belt and the Siberian Platform (Dzheltulak and North Tukuringra transcrustal faults).  相似文献   

The Zagros hinterland fold-and-thrust belt in-sequence thrusting,Iran     

《Journal of Asian Earth Sciences》2014

The collision of the Iranian microcontinent with the Afro-Arabian continent resulted in the deformation of the Zagros orogenic belt. The foreland of this belt in the Persian Gulf and Arabian platform has been investigated for its petroleum and gas resource potentials, but the Zagros hinterland is poorly investigated and our knowledge about its deformation is much less than other parts of this orogen. Therefore, this work presents a new geological map, stratigraphic column and two detailed geological cross sections. This study indicates the presence of a hinterland fold-and-thrust belt on northeastern side of the Zagros orogenic core that consists of in-sequence thrusting and basement involvement in this important part of the Zagros hinterland. The in-sequence thrusting resulted in first- and second-order duplex systems, Mode I fault-bend folding, fault-propagation folding and asymmetric detachment folding which indicate close relationships between folding and thrusting. Study of fault-bend folds shows that layer-parallel simple shear has the same role in the southeastern and northwestern parts of the study area (α_e = 23.4 ± 9.1°). A major lateral ramp in the basement beneath the Talaee plain with about one kilometer of vertical offset formed parallel to the SW movement direction and perpendicular to the major folding and thrusting.  相似文献   

褶皱相关断裂构造形成条件与发育机制:燕山中部露头尺度变形研究为例   总被引：1，自引：1，他引：0       下载免费PDF全文

邓洪旦  张长厚  邓洪菱  欧阳嘉穗 《地学前缘》2012,19(5):61-75

总结了褶皱相关断裂发育机制的3个构造几何学模型:同心圆褶皱模型、膝折带褶皱模型和弯流褶皱模型。基于燕山中部中、新元古界地层中发育的5个露头尺度褶皱及其中、小型断裂构造的实例剖析,探讨了收缩变形过程中褶皱与断裂构造发育时序与褶皱相关断裂构造的产生机制。研究指出,规模与所在褶皱构造相当或略小的断裂构造当中,既有形成时间早于褶皱变形的断层,也有在褶皱变形过程中调节褶皱不同部位应变差异的褶皱相关断裂构造,而且卷入后期变形的早期断裂可能成为制约褶皱成核位置的影响因素,以及成为枢纽叠覆楔构造的形成方式之一。断层位移-距离曲线特征和断层与褶皱变形几何学、运动学关系分析,可用来判断断层、褶皱变形发生相对时序。认为影响褶皱相关断裂构造发育的机制主要有3种:(1)纵弯滑褶皱作用中,翼部顺层滑动受到限制而无法持续时,将通过断层向上切层的方式予以调节,从而形成翼部或转折端揳入逆冲断裂以及背离向斜和指向背斜逆冲断层;(2)各种因素导致的褶皱曲率变化是褶皱相关断裂产生的重要机制之一,褶皱曲率变化可由褶皱轴面的合并和新生直观反映,轴面合并引起褶皱曲率变化的层位,可能是诱发褶皱相关断裂,如背离向斜和指向背斜逆冲构造开始产生的重要部位;(3)能干性差异和强硬层之间距离较大的岩层组合发生纵弯褶皱变形时,软弱岩系在褶皱核部的聚集和逃逸,是迫使递进收缩的强硬层产生褶皱相关断裂构造的重要机制。  相似文献