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1.
渭河盆地的地质构造与构造地貌类型   总被引:4,自引:1,他引:3  
胡孟春 《地理研究》1989,8(4):56-64
渭河盆地位于祁吕系、秦岭纬向构造体系,华夏系、陇西旋卷构造四大构造体系交汇地带,这种地质构造背景是形成盆地构造地貌的基础。按照构造-成因分类原则,对本区构造地貌划分为两级8个类型,又按新构造运动特点划分出相应的亚类。这些地貌类型分布具有东西延伸成带,南北对应,垂向成层具阶梯状的空间配置特点。渭河盆地在四大构造体系制约下,共地堑构造是决定地貌空间配置的主要原因。  相似文献   

2.
冀中南黄土潜蚀地貌与黄土构造节理*   总被引:6,自引:0,他引:6  
王景明  王君 《地理研究》1994,13(1):90-93
本文对冀中南黄土分布区的潜蚀地貌进行了研究后发现,与我国西北黄土区一样,该区黄土潜蚀地貌具有区域性、方向性和空间分带性特征,黄土构造节理控制了相应地区的潜蚀地貌形态、展布方向和发育程度,是黄土潜蚀地貌的构造基础。  相似文献   

3.
李靖 《干旱区地理》1991,14(2):21-27
本文论述了天山南北麓山前地带及山间盆地边缘普遍存在的山前褶皱构造地貌特征。用板块构造理论探讨天山山区的板块运动与山前褶皱构造的成因。  相似文献   

4.
本文在对天山构造地貌形成、演化及构造地貌特征分析的基础上,对天山作为陆内古板缘山的构造、边界及动力条件进行了研究,进而提出了活动性陆内古板缘山地的造山旋回模式。  相似文献   

5.
晚新生代以来,青藏高原北东向扩展,致使祁连山地区遭受了强烈的构造隆升,造就了祁连山地区复杂的构造格局和急剧变化的构造地貌,其典型水系流域地貌特征揭示了该地区的新构造活动和地貌演化过程。庄浪河流域位于祁连山东段,作为青藏高原北东向扩展的前缘地区,庄浪河流域的地貌参数对构造活动非常敏感,提取庄浪河流域的地貌信息,有助于揭示祁连山东段庄浪河流域地貌对构造活动的响应,及系统探讨该区地貌发育特征及其所蕴含的构造意义。庄浪河流域内及边缘发育有庄浪河断裂、天祝盆地南缘断裂、疙瘩沟隐伏断裂以及金强河-毛毛山-老虎山断裂。晚新生代以来,这些断裂仍在活动,并且控制着流域内的构造变形、山体隆升和河流水系地貌发育。本研究采用ALOS DEM 12.5 m数据,基于ArcGIS空间分析技术,通过高程条带剖面、河流坡降指标体系(K,SL,SL/K)和Hack剖面、面积-高程积分值(HI)和积分曲线(HC)等方法,对庄浪河流域地貌特征进行了初步分析。结果表明,庄浪河地区地形起伏由北西向南东递减,构造活动存在东西分异的规律;庄浪河流域内部K值、SL、SL/K、HI值西侧高于东侧,Hack剖面西侧相比东侧上凸更明显;H...  相似文献   

6.
论云南地貌体系   总被引:6,自引:0,他引:6  
阐述了云南地貌学研究发展概况,分析了云南地貌构造体系,进行了云南新构造运动分区。在对云南地貌类型划分的基础上,根据岩石类型、大地构造和地貌形态、特征的相异性,进行了云南地貌分区。  相似文献   

7.
广东地质构造特征及其与地貌发育的关系   总被引:3,自引:0,他引:3  
本文从大地构造运动、各构造旋回中形成的地层岩石特征、新构造运动与外力作用结合等与广东地貌发育的关系,阐述了构造运动控制了地貌发育过程,构造形迹构成了地貌的骨架,沉积建造是地貌形成的本底,新构造运动及外力地质作用最终塑造了现代地貌等地貌成因观点。  相似文献   

8.
阿尔金山及其毗邻地区构造地貌的形成和演化   总被引:4,自引:1,他引:3  
李志中 《地理研究》1994,13(3):35-43
在新构造运动中复活的阿尔金走滑断裂带制约着本区构造地貌的分布格局和发育过程.阿尔金山即是该断裂带所控制的断块发生强烈上升而成的差异性断决山地,以阿尔金山为轴成反对称分布的区域地貌格局也是阿尔金走滑断裂带发生大规模左旋平移和逆冲推覆的产物.本区构造地貌演化则经历了三个阶段,其间断块上升活动西强东弱并自西向东发展,因而形成阿尔金山西高东低的起伏形态.  相似文献   

9.
陈志明 《地理学报》1993,48(2):105-113
该图以多层次表示法和表列式分解型图例,着重表现构造地貌为基础的内外力地貌成因、形态及其发展过程的基本规律。在内力方面,采用板块构造理论为指导,表现了构造地貌;外力方面,除表现传统的堆积成因形态类型外,辅以气候地貌的地带分异;而形态分类则利用DTM,对国土地形进行了基本形态要素的机助分析与制图,并引进地形起伏度概念,调整了传统的形态分类方案。通过项目研制,作者力求探讨一种符合现代地貌学理论,服务于科研、教学和国土整治的新型国家地貌图。  相似文献   

10.
阿尔泰山构造地貌与砂金   总被引:1,自引:1,他引:0  
阿尔泰山构造地貌的基本特征不仅决定了砂金成因类型,也控制着砂金的沉积分布规律,在阿尔泰山不同走向的断裂交汇处往往形成断陷盆地、断陷谷地等负地形、或构成断块山结并发育有放射状水系,它们是对砂金富集成矿极为有利的地貌场所.  相似文献   

11.
中国东部大同火山群发育的构造地貌背景   总被引:6,自引:0,他引:6  
大同火山群是我国东部重要独特地貌类型之一。火山群及其所在的大同盆地位于上地幔隆起带上,受中国东部最突出的构造地貌格局——NNE向雁行右旋剪切拉张断陷带控制。火山群及熔岩溢出带即明显沿着这个右旋剪切拉张破裂带以及与NW压扭性断裂交汇处发育,同时受到断裂多次活动的影响。  相似文献   

12.
The Fore-Alps of western Veneto and Trentino regions belong to the central Southern Alps (NE Italy), in which there is little evidence of very fresh surface ruptures or surface faulting. This does not seem to match historical data about earthquakes, some of which have been very intense. The strong influence of the inherited structures makes it difficult to detect a direct link between morphotectonic features and present-day stress fields.In the present study, four areas (Orsara, Scandole, Naole and Soran) with surface faulting and surface rupture features were examined, and models of morphotectonic evolution are discussed. In the Lessini Mountains, the Orsara graben and Scandole ridge show examples of surface faulting and surface rupture, respectively, reactivating Paleogene normal faults and fractures. Within the Orsara graben, rocky bluffs displace the previous morphological features. The bluffs are some decimetres to some metres high and are practically devoid of evidence of either physical or chemical weathering; on the slopes above them are steep areas which may be interpreted as the remnants of previous strongly weathered bluffs. The Scandole ridge has many trenches, some with rocky walls, which may be the result of several episodes of morphotectonic rupture.In the Giudicarie Belt, the Naole and Mt. Soran surface faulting landforms are details within large frontal culmination walls of Neogene thrusts. The Naole ridge corresponds to the southeastern sector of Monte Baldo. Here, inside a fault angle valley, a sinuous scarp originating from surface faulting marks the base of the fault scarp slope. Ridge splitting is the expression of the backward migration of separation niches due to slope tectonics, also evidenced on the slope by several terrace-like features and by a lower belt of very thick slope breccias. On Mt. Soran, in the Gruppo di Brenta massif, the surface faulting scarp faces uphill, giving rise to a trench-like feature. Downvalley of the scarp, there is the niche of a large landslide dated to 3 kyears B.P.All these landforms are consistent with slope tectonic movements caused by intense earthquakes. Whereas the morphostructures in the Lessini Mountains are the result of responses by sensitive structures, the Naole and Mt. Soran features express the evolution of frontal culmination walls of thrusts, with clear evidence of present-day tectonic activity.On the basis of the weathering of the scarps and associated features, the relative seismotectonic episodes probably occurred between the Bronze and Middle Ages.  相似文献   

13.
The Pakuashan anticline is uniquely suited for study of the forward and lateral growth of fault-related folds. The Pakuashan ridge development arises from the late Quaternary uplift of the most external thrust zone of the western foothills of Taiwan. From Kaoshiung to Taichung, recent and active westward thrusting occurs at the front of the foothills. The Pakuashan anticline, trending N 150°E in the northern part to N 000° in the southern part, has been active throughout the Quaternary period. This activity is marked by geological structures, tectonic geomorphology and seismicity. A multisource and multiscale approach to study of the continental collision setting has been undertaken to combine tectonics, sedimentology and geomorphology. Studies of fracture patterns allow identification of two main features of stress orientations: a WNW/ESE compression direction, and E–W and N–S extension directions. Quantitative geomorphic parameters have been used to define the morphotectonic evolution and to infer tectonic style along the mountain front. Geomorphic evidence provides significant information on the processes that govern lateral propagation of an active anticline. Quaternary terraces are uplifted, tilted and folded over the Pakuashan ridge. Drainage systems in areas of active compression give information on the thrust zone structures and their development. Steep drainage and high local relief indicate that the Pakuashan anticline forms a well-defined zone of high uplift, especially in the southern part. The two main controls on drainage in that area are rock strength in the hanging wall and propagation of the deformation towards the south.  相似文献   

14.
The San Lorenzo area belongs to the Esmeraldas–Tumaco seismic zone where some of the strongest earthquakes of South America occurred during the 20th century. This paper provides evidence for a succession of geomorphic changes characterized by the disruption of the Quaternary drainage network and the reshaping of the Cayapas–Santiago estuary. The rise of the La Boca uplift bordered by the La Boca and San Lorenzo faults is responsible for the southward diversion of the Palabi, Tululbi, Bogotá and Carolina rivers toward the Santiago and Cayapas rivers. The increase of the discharge directed to the Cayapas River generated the change of the channel pattern downstream from the confluence, and the avulsion of a new estuary through the coastal plain. According to the dating of beach ridges the avulsion occurred in the period 3200–2800 BP. This period corresponds also to a faster accretion of the beach ridge margin, interpreted as a response to a small uplift of the shore. The coherency of the three morphologic evidences—diversion of drainage network, avulsion and increase of coastal accretion—suggest a unique morphotectonic event, in relation with the activity of the Esmaraldas–Tumaco seismic zone. The opening of a direct communication through the mangrove margin may have brought favorable conditions for the development of the La Tolita archaeological site after 3000 BP.  相似文献   

15.
Integration of landform and structural analysis allowed the identification of Late Pleistocene–Holocene pulses of tectonic activity in the Campos do Jordão Plateau with ages and regimes similar to the ones from the continental rift. Fault reactivation along Precambrian shear zones give rise to a series of conspicuous morphotectonic features, determine the formation of stream piracy phenomena, and divide the plateau into smaller blocks. Recognition of these tectonic pulses as well as of their effects in landform development—particularly clear on the Campos de São Francisco at the highest area of the SE edge of the plateau—show that besides the climate-related Quaternary environmental changes significant neotectonic instability should be considered in the geomorphic evolution of the Campos do Jordão Plateau.  相似文献   

16.
《Geomorphology》1995,12(1):37-44
In southeast Australia the history of river development, basin sedimentation and the evolution of major divides can all be related. The region has a basement of Palaeozoic rocks eroded to a palaeoplain. Two sedimentary basins are separated by a system of tectonic warp axes that correspond closely to drainage divides. The Great Artesian Basin (GAB) is Mesozoic; the Murray Basin is Cenozoic. The Cretaceous-Cenozoic Gippsland-Otway Basin lies to the south, and a Cenozoic sedimentary wedge on the continental shelf to the east.In the Jurassic, before the breakup of Gondwana, Australia extended further east and south. Rivers from the south and east provided coarse sediment to the GAB.The catchment of Jurassic drainage was bounded to the east by the Tasman Divide. Downwarping of the palaeoplain formed the east-west Victoria Divide and the Gippsland Basin in which Cretaceous sediments accumulated. Rifting and seafloor spreading formed the Tasman Sea, starting about 80 m.y. ago. The palaeoplain was downwarped, creating the Great Divide and a new continental shelf on which marine sediments accumulated. Drainage from the Victoria Divide and the Great Divide continued to flow to the GAB until the Murray Basin started to subside in Paleocene times. A new warp axis, the Canobolas Divide, appeared between the GAB and the Murray Basin. Basically west-flowing drainage developed across the Murray Basin, Cenozoic sediments accumulated, and sediment supply to the GAB was further depleted.Ancillary features consistent with this morphotectonic history include: Ancient channels with gravels cross the Victoria, Great and Canobolas Divides. Volcanicity follows the warp axes. Reversed rivers are found on the coastal side of the Victoria and Great Divides. Deposition on the continental shelf is roughly equal to erosion on land. The change from coarse to fine sediment which gives the GAB its artesian character fits with the shrinkage of its catchment. The Divides are in different stages of erosion consistent with their ages.The morphotectonic development of southeast Australia, with responses to non-cyclic unique events on the time scale of global tectonics, is an example of evolutionary geomorphology.  相似文献   

17.
Mapping of lateritic bauxites over the West African rifted margin and analysis of the geomorphic properties of these bauxites, combined with available geological data lead to a discussion of the presence of either two Meso-Cenozoic planation surfaces or a single Eocene surface to account for the morphotectonic and paleoclimatic evolution of the Guinean landforms. At large scale, two stepped bauxitic levels are documented. Ongoing or episodic uplift following Gondwana breakup and Meso-Cenozoic climate change are proposed to have allowed the formation and abandonment of an Early mid-Cretaceous surface today preserved as the higher bauxitic level, and the setting of an Eocene planation surface bearing a second generation of bauxites, making the lower bauxitic level. The single Eocene surface hypothesis requires that Paleogene bauxitization preserved large pre-existing relief to explain two stepped bauxitic levels of the same age. The two-surface hypothesis is favored because it would explain rebauxitization of alluvial pebbles of bauxites under the lower lateritic level.  相似文献   

18.
The Khazar fault is an active thrust fault in the northern part of the Alborz Range, which is associated with folding (the Khazar anticline) in its hanging‐wall. Regional geological studies indicate activity of the fault in Cenozoic time, and active propagation of the fault‐related folding towards the west. The Neka river drainage basin, which is a longitudinal river flowing mostly in the backlimb of the Khazar anticline, shows evidence for active folding and faulting influencing drainage evolution. Observations are made in different parts of the Neka river course, according to which a new morphotectonic feature is introduced within the river basin, termed as ‘tilted reach’. This feature is considered as a result of river course tilting in the backlimb of the growing fold, diversion, and capture of the river by other rivers. Consecutive episodes of similar events would have resulted in the development of a long drainage basin parallel to the growing fold structure.  相似文献   

19.
中国石油资源流动源—汇系统空间格局特征   总被引:9,自引:1,他引:8  
以中国石油(特指原油) 资源流动为研究对象,把中国省级行政单元抽象为石油资源流动节点,从1985-2009 年中选取5 个特征时点,根据各流动节点石油自给能力及流动比率,将各特征时点的石油流动省份划分为源地、汇地和交流地3 大流动职能类型,并将主要石油进口港(含陆上口岸) 作为进口石油源地;分别利用重心和标准差椭圆分析源地系统和汇地系统空间分布格局的集中与离散趋势,得出中国石油资源流动源—汇系统空间格局的位移和形变特征.结果表明:① 源地系统重心位于中国东偏北部,在经历了1985-1995 年的西北向移动后,1995-2009 年大幅向西南偏移,南北方向的移动速度快于东西方向;汇地系统重心偏于中国中东部,移动幅度相对较小,1985-1999 年呈南北向移动、1999-2003 年呈东西向移动,最终快速向西南方向偏移.② 从标准差椭圆分析来看,源地系统的空间分布先趋于分散后又趋于集中,由东北—西南的分布格局逐渐趋向于西北—东南的分布格局;汇地系统空间分布格局相对较为稳定,小幅极化后略趋分散,呈较为稳定的东北—西南分布.③ 中国石油资源流动的平均方向由东北—西南向偏转为南北向,平均运距呈下降趋势,主导流向由东北—西南向逐步转变为西北—东南向和东西向输流并存.  相似文献   

20.
Geomorphic analysis, employing topographic, morphologic, geologic, and bathymetric maps, and field studies show that the morphology of the southern coast of Mexico can be linked to lateral variations in the geometry and tectonism of the subduction zone. A reconnaissance study, based on the regional morphological characteristics and correlation with seismotectonic segments, regional tectonics and major bathymetric features, allows identification of several morphotectonic zones along the coast of southern Mexico: (1) Jalisco zone, (2) Colima zone, (3) Michoacan zone, (4) Guerrero zone, (5) Oaxaca zone, and (6) Tehuantepec zone. A range of geomorphological evidence, including marine terraces, river terraces, uplifted notches, and elevated wave-cut platforms, indicates local and regional uplift along the coast of the Jalisco, Michoacan, Guerrero and Oaxaca zones. Coasts of the Colima and Tehuantepec zones show morphological evidence of subsidence.  相似文献   

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