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1.
I.S. Novikov O.V. Cherkas G.M. Mamedov Yu.G. Simonov T.Yu. Simonova V.G. Nastavko 《Russian Geology and Geophysics》2013,54(3):324-334
The fault system reflected in the topography and structure of Cenozoic cover sediments in the Kuznetsk Basin is mostly recent. The positions of recent faults match those of Paleozoic and Mesozoic disjunctive dislocations only at the Kuznetsk Alatau and the Salair Range boundaries. These marginal features are associated with the greatest amplitudes of vertical movements in recent time: 80–100 m; less frequently, up to 250 m in the north and within 600 m in the south. The recent disjunctive dislocations are generally fractured zones from 300 to 2000 m in width, which were occupied by watercourses during the formation of the erosion valley system. Except for marginal recent tectonic bodies, vertical movements along the majority of recent faults do not exceed 5–10 m, reaching 30–70 m at the boundaries of recent tectonic regions and subregions. There is no reliable evidence of notable horizontal movements. For particular bodies, it is conjectured to be within 300–700 m by analogy with other regions of the Altai–Sayan folded area.The recent fault pattern can be interpreted as a result of crushing by submeridional compression with a slight right slip. The types of recent tectonic activity are different in different areas of the depression. The smallest uplift is recorded in the north of the basin, where the elevations of the Late Cretaceous peneplain are within 300 m, being within 230–250 m in the near-Salair subregion. This points to an insignificant downwarping in this area. Vertical movements along recent faults within the region are small, and the most intense movements are at its boundary. The central region is slightly elevated with reference to the northern one, and the elevation of its planation surface is within 300–380 m. It is characterized by differentiated movements along block boundaries with amplitudes reaching 60–70 m. The maximum activity occurred in the southern region. The elevations of its Late Cretaceous peneplain vary from 400 to 600 m. This region is characterized by notable vertical movements along block boundaries in the form of straight tectonic scarps and valleys. The northern and central regions constitute the present-day Kuznetsk intermontane depression, whereas the southern region belongs to the periphery of the mountainous framing of the Kuznetsk Depression. 相似文献
2.
《Geodinamica Acta》2013,26(1):51-71
Neotectonic movements have been proposed in the literature in order to explain some landforms of the equatorial passive margin of northeastern Brazil. Its seismo-tectonic activity is concentrated in a few sectors located on or near the coast. Active or recently active structures are mainly identified in Neogene deposits. Identifying a contribution of neotectonics to the morphogeny is difficult in a context where most major morphostructural patterns are explained by Cretaceous tectonics related to oceanic opening and by differential erosion induced by Tertiary epeirogenic uplift. We aim to assess the nature of features considered as possibly neotectonic in origin. Seismogenic faults are not related to significant topographic breaks, except on the coast, where they usually reach only a few meters in height. A study of landforms located near zones of seismo-tectonic activity indicates a possible, probably weak, contribution of neotectonics to the formation of a few high scarps. These scarps occur along or near fault zones reactivated in Cretaceous times. We conclude that neotectonic movements are the result of ongoing deformation along predominantly strike-slip fault zones, with long term deformation rates similar to those recorded by dated landmarks (0.01 mm.yr -1). Despite reported deformation rates that can amount in places to 0.4 mm.yr -1, neotectonic rates are lower than erosion rates. The consequence is that major structural landforms in the region mainly originated in Cretaceous to early Tertiary events. 相似文献
3.
R. Rexford Upp 《Engineering Geology》1989,27(1-4):375-412
The Maacama fault zone is a north-northwest trending, right-lateral zone of structural weakness in eastern Sonoma and Mendocino Counties, California, and fault-related landforms along its trace suggest that it may well have been active during Holocene time. Urbanization and dam construction in the vicinity of the zone have made it especially desirable to determine the extent and history of such geologically recent movements in order to better understand the seismic capability of faults within the zone.
The Maacama fault zone is a segment of one of two north-northwest trending zones of right-lateral faulting that diverge as major branches from the easterly side of the San Andreas fault zone north of Hollister. These branches extend at least as far north as Eureka and may mark the eastern boundaries of slivers of a separate tectonic plate.
This investigation was conducted to evaluate Holocene activity along the part of the Maacama fault zone in Mendocino County. The investigation shows that this zone comprises discontinuous, subparallel fault strands which extend from points south of the Sonoma—Mendocino county line to points north of Laytonville. Some fault segments are expressed by alignments of topographic features clearly caused by Holocene strike-slip movements. Other topographic features are less distinct and may well represent fault segments with pre-Holocene activity.
The Maacama fault zone creeps at a current rate of possibly as high as 2 mm/yr. The total amounts of Holocene offset are unknown.
Evidence obtained from exploratory trenches indicates that at least two surface rupture events have occurred within the past 16,200 years, that at least one has occurred within the past 8,310 years, and that there probably has been no surface rupturing within the past 1,140 years.
I conclude that surface offsets have occurred along major portions of the Maacama fault zone during Holocene time, and that this fault zone should be regarded as capable of producing a moderate to strong future earthquake with accompanying surface rupture in Mendocino County. 相似文献
4.
I. Yu. Lobodenko 《Moscow University Geology Bulletin》2010,65(2):115-120
This article considers the problem of the seismic activity of the Kheiton fault located in the northern part of Sakhalin Island.
The fault is active, well expressed in relief, displaces Holocene deposits, and is studied by trenching. Its geomorphological
expression, as well as the character of displacement of rock strata in the trench walls and the relief was investigated. Convincing
evidence is provided for periodic sudden movements along the Kheiton fault with amplitudes of up to several meters, which
in their turn have recently caused strong earthquakes. 相似文献
5.
中国喜马拉雅构造运动的陆内变形特征与油气矿藏富集 总被引：12，自引：0，他引：12
在前人研究的基础上,结合近年来在油气勘探中不断积累的地质资料和地质认识,提出了中国喜马拉雅构造运动的陆内变形特征及其分布规律受控于小型克拉通板块拼贴的基底结构和印/欧碰撞与太平洋板块俯冲所主导的双重控制因素;喜马拉雅构造运动的发育特征主要表现为三种动力学机制:青藏高原隆升、盆地与造山带体制和东部拉张活动。喜马拉雅构造运动的大地构造格局及其构造变形分布规律集中体现为4个构造域:青藏高原隆升区、环青藏高原盆山体系、稳定区和环西太平洋裂谷活动区。我国沉积盆地在喜马拉雅构造运动中的构造特征分为三种类型:(1)东部渤海湾、松辽等盆地受拉张构造环境控制的裂谷沉降;(2)中部四川、鄂尔多斯等盆地受青藏高原的向东推挤、盆缘冲断、盆内抬升剥蚀;(3)西部的塔里木、准噶尔、柴达木等盆地受青藏高原的向北推挤、冲断挠曲沉降,表现为克拉通单边或双边的压缩挠曲沉降与克拉通内部的冲断隆升沉降等多种盆山耦合形式。喜马拉雅构造运动控制着中国油气晚期定位与富集成藏,主要体现在:盆地的沉积与成藏,形成新生界自生自储的含油气盆地和油气藏;圈闭形成与油气运聚成藏;早期油气藏的调整和再分配;油气藏的破坏。 相似文献
6.
Tadesse Yihunie 《International Journal of Earth Sciences》2002,91(5):922-933
Polydeformed and metamorphosed Neoproterozoic rocks of the East African Orogen in the Negele area constituted three lithostructurally distinct and thrust-bounded terranes. These are, from west to east, the Kenticha, Alghe and Bulbul terranes. The Kenticha and Bulbul terranes are metavolcano-sedimentary and ultramafic sequences, representing parts of the Arabian-Nubian Shield (ANS), which are welded to the central Alghe gneissic terrane of the Mozambique Belt affinity along N-S-trending sheared thrust contacts. Structural data suggest that the Negele basement had evolved through three phases of deformation. During D1 (folding) deformation, north-south upright and inclined folds with north-trending axes were developed. East and west-verging thrusts, right-lateral shearing along the north-oriented Kenticha and Bulbul thrust contacts and related structural elements were developed during D2 (thrusting) deformation. The pervasive D1 event is interpreted to have occurred at 620-610 Ma and the D2 event ended prior to 554 Ma. Right-lateral strike-slips along thrust contacts are interpreted to have been initiated during late D2. During D3, left-lateral strike-slip along the Wadera Shear Zone and respective strike-slip movements along conjugate set of shear zones were developed in the Alghe terrane, and are interpreted to have occurred later than 557 Ma. The structural data suggest that eastward thrusting of the Kenticha and westward tectonic transport of the Bulbul sequences over the Alghe gneissic terrane of the Mozambique Belt, during D2, were accompanied by right-lateral strike-slip displacements along thrust contacts. Right-lateral strike-slip movements along the Kenticha thrust contact, further suggest northward movement of the Kenticha sequence during the Pan-African orogeny in the Neoproterozoic. Left-lateral strike-slip along the orogen-parallel NNE-SSW Wadera Shear Zone and strike-slip movements along a conjugate set of shear zones completed final terrane amalgamation between the Arabian-Nubian Shield and the Mozambique Belt in Neoproterozoic southern Ethiopia. 相似文献
7.
Backstripped basement subsidence histories from both the hanging wall and the footwall blocks adjacent to synsedimentary normal faults can be used to reconstruct the sense of fault motion through time and to quantify the vertical component of fault slip. Consequently, apparent dip-slip rates of faults can be calculated for each stratigraphic interval and times of increased fault activity can be distinguished. An application of this method to well data along a transect through the central part of the Miocene Vienna Basin indicates that two distinct phases of faulting occurred during the Karpatian, with rates as high as 3000 m Myr−1 . Changes in the sense of movements during the early Karpatian and the earliest Badenian indicate a major rearrangement in the fault patterns. During the early Sarmatian another short pulse of dip-slip is recorded along the investigated faults. 相似文献
8.
张文佑院士是我国最杰出的构造地质学家和大地构造学家,他提出和倡导的地质构造力学分析和历史分析相结合及断块构造理论符合当代构造地质和构造运动研究的新方向。断块构造是地球构造运动最基本的型式,板块构造是全球范围内的岩石圈构造,是最高一级的岩石圈断块构造。活动断块是现今构造运动最基本的型式,它既控制主要活动构造带和地震活动带的分布,也控制不同地区地震活动特征的差异。断块边界构造带是在构造变形和运动场中的不连续变形带,应力在此释放,应变在此局部化,位移在此发生,其差异活动最为强烈,因此,断块边界构造带是强震发生带,其活动性质会控制震源断层的特性。大地震孕育和发生在边界活动构造带的某些特殊部位,对其成核的构造和物理过程尚需深入进行研究。要特别注意断块整体性活动对地震活动的控制作用,断块的这种整体性活动与一定时期内地震活动主体地区分布有密切关系,所以,在活动构造研究中,要把断块的整体性活动与活动构造带的个体活动结合起来。 相似文献
9.
Forty‐four tremors which occurred in the Snowy Mountains of New South Wales during the years 1958–1962 have been accurately located, using a network of seismic stations operating in that area. The largest of these were a tremor of magnitude 5 north of Berridale in May, 1959, and one of magnitude 4 near Rock Flat in September, 1958. Fault plane analysis suggests that the former was caused by a high‐angle thrust movement along the plane of the Crackenback Fault, while the latter may be associated with the Murrumbidgee Fault. These conclusions are supported by macroseismic data. Twenty‐one minor shocks occurred in the vicinity of the Berridale tremor, and their strain release pattern is that of an after‐shock sequence. It is believed that they were produced as a result of secondary strains imposed by the original motion along an edge of the faulted block. The first motion data for these shocks is consistent with the hypothesis that the associated movements were transcurrent. With the decrease of activity in the Berridale region, tremors became more or less random in the Snowy Mountains. The strain release curve obtained for these movements suggests a gradual rebuilding of the stress field following the Berridale shock. 相似文献
10.
则木河断裂带具有构造活动强烈、地震活跃、次生地质灾害严重的特点。本文以鹅掌河流域为例,通过对断裂的活动特征,地质灾害的分布规律、长期活动性与成因机制和地貌演化进行分析,研究得出:（1）则木河断裂带活动特征影响地质环境的演化。新构造运动引起断裂带局部应变失衡,断裂活动诱发频繁地震;隆起和断陷断块的差异性活动,加剧地貌演化与地表过程;沉积建造环境的不同,影响岩土体的剥蚀与沉积;断裂的掀斜运动,改变地表水系格局与地热运移。（2）活动断裂对地质灾害的控制作用,表现为灾害具有时空效应。空间上,灾害沿断裂带呈带状分布,沿水系呈线状分布,具有地层倾向性,集中于断裂破碎带的软岩,微地貌效应显著;时间上,现有地质灾害在多次地震扰动和强降雨触发下形成,鹅掌河形成高频泥石流。（3）断裂活动影响灾害成因机制和灾害类型及破坏模式,脆弱的地质环境在地震持续扰动和极端降雨的耦合作用是灾害频发的根本原因;依据灾害成灾机制,将灾害分为3大类,7小类,具有震裂斜坡的典型破坏模式。（4）活动断裂与地质灾害相互作用决定地貌演化。鹅掌河泥石流影响邛海的地貌变迁,通过计算构造隆起量与灾害剥蚀量,表明鹅掌河处于隆起区,邛海处于淤积区。由此可见,则木河断裂活动特征通过影响区域地质环境演化,诱发大量的地震地质灾害,最终由地震构造作用驱动的隆起和断陷,地表灾害过程驱动的剥蚀和淤积,两者相互作用决定现有地貌的演化。 相似文献
11.
Extensive deformations of mountain slopes occur in crystalline intrusive rocks in the southern Coast Mountains of British Columbia. Typical morphological evidence of slope movement includes extensive systems of tension cracks, grabens, and antislope scarps (collectively referred to here as linears). These landforms involve displacements along penetrative joints observed in surface exposures. Kinematic tests on rock-structural data indicate that the observed patterns of linears are generally consistent with the feasible gravitational movements along the dominant discontinuities. Most sites indicate sliding as the most likely initial mode of movement, followed by or accompanied by toppling and toppling-induced sliding movements, and do not support the view that linears are the traces of active faults. 相似文献
12.
利用地震后2009 ～ 2011年GPS监测数据,获得了龙门山断裂带所在地区2009～2010年、2010～2011年以及2009～2011年GPS测站运动速度场,分析了区域地壳运动总体趋势及形变特征;通过分析龙门山断裂带北段、中段、南段横切剖面的测站运动速度变化,探讨了汶川地震后龙门山断裂带运动特征.分析表明:汶川地震前后,地壳运动总体趋势未变,作顺时旋转;断裂带西侧GPS测站运动速度变大,东侧运动速度变小;龙门山断裂带的断裂性质地震前后都为右旋走滑挤压,断裂带运动速率受汶川地震影响较大,震后运动速率较震前有显著的增加.龙门山断裂带震后各段次级断裂活动不同,中南段以前山断裂运动为主,其它各段以后山断裂运动为主.地震后龙门山断裂带表现出的运动特征主要与地震活动有关.受汶川地震的影响,区域动力学、运动学平衡被打破,龙门山断裂带东侧震后初期弹性回返,表现为低速反向运动.龙门山断裂带西侧震后松弛为拉张区,运动速度加大.地震对断裂带的影响不同,导致断裂带各段及次级断裂表现出不同的运动特征. 相似文献
13.
A. I. Konyukhov 《Lithology and Mineral Resources》2011,46(6):528-545
Among petroliferous regions of the world, a specific place is occupied by sedimentary basins confined to continental margins
at the eastern periphery of the Pacific Ocean and in the Caribbean Sea. In the Cenozoic and Quaternary, this region was dominated
by tectonic activity manifested as compression, movements along large fault systems (primarily, strike-slip faults), formation
of mountain chains, appearance of thick accretion prisms and foothills, and development of volcanism at certain stages. The
petroliferous structures of the region are mainly represented by fore-arc sedimentary basins complicated in some places by
fore- and backdeeps. 相似文献
14.
The Kangra Re-entrant in the NW Himalaya is one of the most seismically active regions, falling into Seismic Zone V along the Himalaya. In 1905 the area experienced one of the great Himalayan earthquakes with magnitude 7.8. The frontal fault system – the Himalayan Frontal Thrust (HFT) associated with the foreland fold – Janauri Anticline, along with other major as well as secondary hinterland thrust faults, provides an ideal site to study the ongoing tectonic activity which has influenced the evolution of drainage and landscape in the region. The present study suggests that the flat-uplifted surface in the central portion of the Janauri Anticline represents the paleo-exit of the Sutlej River. It is suggested that initially when the tectonic activity propagated southward along the HFT the Janauri Anticline grew along two separate fault segments (north and south faults), the gap between these two fault and the related folds allowed the Sutlej River to flow across this area. Later, the radial propagation of the faults towards each other resulted in an interaction of the fault tips, which caused the rapid uplift of the area. Rapid uplift resulted in the disruption and longitudinal deflection of the Sutlej river channel. Fluvial deposits on the flat surface suggest that an earlier fluvial system flowed across this area in the recent past. Geomorphic signatures, like the sharp mountain fronts along the HFT in some places, as well as along various hinterland subordinate faults like the Nalagarh Thrust (NaT), the Barsar Thrust (BaT) and the Jawalamukhi Thrust (JMT); the change in the channel pattern, marked by a tight incised meander of the Beas channel upstream of the JMT indicate active tectonic movements in the area. The prominent V-shaped valleys of the Beas and Sutlej rivers, flowing across the thrust fronts, with Vf values ranging from <1.0–1.5 are also suggestive of ongoing tectonic activity along major and hinterland faults. This suggests that not only is the HFT system active, but also the other major and secondary hinterland faults, viz. the MBT, MCT, SnT, NaT, BaT, and the JMT can be shown to have undergone recent tectonic displacement. 相似文献
15.
Geomorphic and seismic data relative to one of the major faults of Iran, the Doruneh Fault, are presented. It is shown that along its eastern section, the fault is presently active and connected with two destructive earthquakes during the twentieth century. Contrary to previous assumptions, recent and probably contemporary movements along it are essentially in the vertical direction. 相似文献
16.
No region is excluded from actions of recent geodynamic short- or long-term effects which can be observed even on the Earth’s
surface. The article delivers a geodynamic hazard assessment for the anthropogenic objects threatened by permanent shear movements
occurring along tectonic faults and a way how to mitigate and/or eliminate the object risk. The proposed approach is applied
to a case example of a motorway tunnel leading through rock masses where dynamically active zones with shear movements along
their faults are expected. To detect the shear movements among rock masses, the contemporary satellite geodetic GPS methodology
was used. 相似文献
17.
台湾海峡地区横向构造及其对东南沿海地震的作用 总被引：1，自引：0，他引：1
台湾海峡两岸存在一系列断续分布、横贯台湾海峡的NW向断裂,研究表明为一系列具有走滑运动的横向构造,根据地壳运动、区域变形和断裂特征分为巴士断裂带、台中-晋江断裂带和宁德-三貂角断裂带。中部的台中-晋江断裂带是一条控制地壳运动南北差异的重要分界断裂,断裂带以北的东南沿海北部和台湾北部地壳整体向东运动,与琉球俯冲带右行走滑运动方向基本相同,形成一致的变形取向;断裂带以南处于华南地块与菲律宾海板块相向运动挤压变形环境,地壳变形比北部强烈。东南沿海地震强度增强趋势、地震南强北弱与该应变场和横向走滑有关:(1)由于该断裂以南比以北地区应力应变场变化大,多场耦合复杂,耦合程度降低,造成蠕动变形不均产生应力闭锁,孕育地震发生。(2)福建东部比台湾海峡地壳均一性差、地球物理场变化明显,组成更为复杂的多元、多场耦合,耦合场稳定性差,容易受横向构造活动干扰,产生弹性变形而孕育地震强度增强。 相似文献
18.
A numerical model to predict landslide movements along pre‐existing slip surfaces from rainfall data is presented. The model comprises: a transient seepage finite‐element analysis to compute the variations of pore water pressures due to rainfall; a limit equilibrium stability analysis to compute the factors of safety along the slip surface associated with transient pore pressure conditions; an empirical relationship between the factor of safety and the rate of displacement of the slide along the slip surface; an optimization algorithm for the calibration of analyses and relationships based on available monitoring data. The model is validated with reference to a well‐monitored active slide in central Italy, characterized by very slow movements occurring within a narrow band of weathered bedrock overlaid by a clayey silt colluvial cover. The model is conveniently divided and presented in two parts: a groundwater model and a kinematic model. In the first part, monthly recorded rainfall data are used as time‐dependent flow boundary conditions of the transient seepage analysis, while piezometric levels are used to calibrate the analysis by minimizing the errors between monitoring data and computed pore pressures. In the second part, measured inclinometric movements are used to calibrate the empirical relationship between the rate of displacement along the slip surface and the factor of safety, whose variation with time is computed by a time‐dependent stability analysis. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
19.
The Cantabrian Mountains, containing about 70% of the total coals of the country and 95% of the anthracitic and bituminous resources, is the most important coal-mining district of Spain. Coal-bearing successions are Late Carboniferous in age and their deposition took place in a syn-orogenic context during the Hercynian activity, mainly in three different time-successive locations: foreland basins, intrathrust basins and intramontane fault-controlled basins. Foreland deposition occurred in strongly asymmetrical basins located ahead of thrust sheets units. Intrathrust basins resulted from folding and tightening of these units during or after their emplacement. Intramontane and fault-controlled basins were developed along lineaments with strike-slip movements and as a result of fold and fault reactivation. Peat mires in foreland and intrathrust coal basins mainly occupied broad areas on abandoned delta and fan delta lobes. Coals in intramontane and fault-controlled basins were related with alluvial fan and lacustrine environments. Coal ranks vary from high volatile bituminous coals to anthracite, depending on the structural location of the coalfields. Hydrothermal activity seems to be the most important factor in coal evolution. 相似文献
20.
《Journal of African Earth Sciences》2008,50(4-5):211-221
The Late Panafrican evolution of the Hoggar shield is characterized by emplacement of magmatic intrusions and by occurrence of major shear zones separating different terranes. In Telloukh granite is close to the In Guezzam faults (western border of the Tin Serririne basin). Analysis of its visible and magnetic fabrics suggests an emplacement mode and deformation that are not related to the In Guezzam faults, but most likely to a N–S compression, an event not yet identified. Dioritic dykes crosscutting the granite have a very different magnetic fabric, which is related on the contrary to dextral strike-slip movements along the In Guezzam faults. In both cases, no visible fabric can be correlated with the magnetic fabric, which has been likely acquired during late magmatic stages. This magnetic fabric was not significantly affected by the tectonic events that took place after entire crystallization of the magma. The In Guezzam faults and the major 7°30 and 4°50 shear zones are close to intrusions such as In Telloukh dykes and the Alous En Tides and Tesnou plutons where quite similar magnetic fabrics are observed, all related with dextral strike-slip movements along these structures. 相似文献