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广东省主要地质灾害发育特点与防治对策 总被引：6，自引：3，他引：6
广东省主要地质灾害类型有崩塌、滑坡、泥石流、地面塌陷、地裂缝、地面沉降、水土流失等。其中以崩塌、滑坡及地面塌陷为主，多分布在粤东、粤西和粤北等广大中低山区和丘陵区。具有点多面广，活动频繁，危害严重特点。据不完全统计，“九五”期间全省共发生较大规模突发性地质灾害217处，死亡497人，伤597人，直接经济损失约17．43亿元。过量抽取地下水引起的地面沉降主要分布于湛江市区。至2001年，沉降中心最大累计沉降量达178．7mm；工程作用引起的地面沉降(软土地基压缩变形)，主要分布在珠江三角洲及潮汕平原地区。地质灾害主要诱发因素是降雨和人类工程经济活动。根据地质环境条件和致灾地质作用特征将全省划分为5个地质灾害区：粤北中低山崩塌、滑坡、泥石流、地面塌陷为主的地质灾害发育区(I)；粤西低山丘陵滑坡、泥石流灾害、地面塌陷为主地质灾害发育区(Ⅱ)；粤东低山丘陵崩塌、滑坡灾害、水土流失为主的地质灾害发育区(Ⅲ)；沿海台地平原区软土地基沉降、风暴潮地质灾害发育区(Ⅳ)；珠江三角洲平原台地地区软土地基沉降、地面塌陷为主的地质灾害发育区(V)。论文还提出了广东省地质灾害防治对策。 相似文献
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唐山是我国北方岩溶塌陷地质灾害多发地,1976年唐山大地震以来,岩溶塌陷已发生多起。在分析岩溶发育现状的基础上,描述了该区的岩溶发育特征,进而研究了岩溶塌陷的成因机理。研究认为,采矿活动和过量开采岩溶地下水是造成岩溶塌陷的直接诱因,它直接改变了地下水动力条件,局部形成了水位漏斗;地面建筑物的重力荷载、煤矿透水灾害和地震等将直接导致岩溶塌陷地质灾害的发生。据此提出了较为具体的防治措施。 相似文献
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广东沿海陆地地质环境质量定量评价研究 总被引：13，自引：1，他引：12
广东沿海陆地不仅是我国经济较为发达的地区 ,而且也是地震、水土流失、崩塌、滑坡、地裂缝、地面沉降、岩溶塌陷、软土地基形变等地质灾害较为频发的地区。基于对广东沿海陆地主要物理地质灾害形成条件与影响因素调查、统计与分析 ,将广东沿海陆地地质环境质量划分 :构造稳定性、斜坡稳定性和地基稳定性三个质量层面 ,进而构造了隶属三个层面的指标体系 ,该指标体系包括活动断裂、地震活动、地形起伏度、斜坡坡地、冲沟切割密度、水土流失程度、崩滑面密度、土体承载力和地裂缝面密度 9个指标。基于地质环境质量五值逻辑等级取值 :优等、良好、中等、较差和差等 ,对评价指标进行了相应地量化分级取值和标准化处理 ,在建立指标专家权重体系和线性隶属函数的基础上 ,构造了模糊数学综合评价模型。基于 Fortran程序对 190个剖分单元指标数据进行了模型运算 ,将广东沿海陆地地质环境划分为五个质量级共 17个地质环境质量单元。 相似文献
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河北平原地裂缝分布特征及成因机制研究 总被引：14，自引：8，他引：14
河北平原是地裂缝地质灾害较发育的地区。通过河北平原地裂缝地质灾害时空分布规律研究,对河北平原地裂缝形成的主要因素及成因机制进行了研究。河北平原地裂缝主要分布在山前冲洪积扇裙区,发育在全新世地层中。地裂缝地质灾害平面形态上可分为直线型、雁列型、锯齿型、折线型和弯曲形。地裂缝地质灾害空间分布上有方向性、群集性和系统性。河北平原地裂缝分布范围呈逐渐扩大的趋势;分布区域从时间上呈逐渐由南向北扩展之势。河北平原从时间上地裂缝发育条数和发育长度随时间各有不同特点。导致河北平原地裂缝发生的主要因素有地震构造、地下水超采和地面塌陷。 相似文献
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贵州二叠系茅口组古岩溶及其埋藏型地下水系统研究 总被引：2，自引：1，他引：1
二叠系茅口组古岩溶发育,在一定的构造组合下构成埋藏型地下水系统。本文探讨了贵州省茅口期古岩溶地貌类型及空间分布、不同类型古地貌区的岩溶发育特征,进而对茅口组埋藏型地下水系统和地下水赋存条件进行了探讨。研究结果认为,贵州省茅口期古岩溶地貌可分为台地、斜坡和盆地三大类型,其中古斜坡和台地中的岩溶谷地以及硅质岩分布区茅口组古岩溶最为发育,成为省内茅口组埋藏型地下水系统中最有利的赋存地带。 相似文献
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丁琛 《中国地质灾害与防治学报》2020,31(6):122-129
近年来,广州市花都区花东镇、花山镇发生多起岩溶地面塌陷,而对该地区岩溶发育规律研究较为薄弱,故本次利用《广东省广州市地质灾害详细调查（1:50 000）》项目平台,以"点面结合"为手段,采用野外调查配合钻探、物探等方法研究花东镇、花山镇南部冲洪积平原岩溶发育规律、规模及成因。研究表明,本区属于岩溶强发育区,主要为埋藏型岩溶,受地形地貌、地层岩性、地质构造、地下水特征等因素控制,人类工程活动通过改变地下水平衡,促进岩溶的发育。地形地貌和标高控制研究区岩溶的纵、横向发育,纵向上主要分布在-15~-10 m标高段,向上下两侧依次递减,横向上一般分布在地势低洼地段。而在相似地质环境条件下,岩溶发育的规模及数量与Ca2+的含量呈正相关。 相似文献
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北京地区突发性地质灾害危险度评价 总被引：1，自引：0，他引：1
赵忠海 《地质灾害与环境保护》2009,20(3):39-44
北京地区地质构造条件复杂,新构造活动频繁,人为活动剧烈,故地质灾害较为发育。主要的突发性地质灾害有泥石流、采空塌陷、崩塌以及地裂缝等。本文在北京市各区县地质灾害调查与区划工作的基础上,对北京地区的突发性地质灾害的发育情况进行了深入调查和分析。采用袭扰系数法,对突发性地质灾害的易发程度进行了综合评价。采用模糊综合评判模型,对影响地质灾害演变趋势的降雨条件、人类工程活动、地震活动以及区域岩组结构等因素进行了综合评判。并在此基础上．对突发性地质灾害的危险度进行了评价和预测,将北京地区划分出了地质灾害高风险区、地质灾害中风险区及地质灾害低风险区。 相似文献
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城市岩溶塌陷地质灾害风险评估--以贵州六盘水市为例 总被引：9，自引：0，他引：9
岩溶塌陷是我国岩溶区主要地质灾害.它和崩塌、滑坡、泥石流以及地面沉降、地裂缝等构成我国6大地质灾害类型.随着我国"地质灾害防治管理办法”的颁布和实施,不同灾种的风险评估已成为地质灾害防治管理的重要内容.针对城市岩溶塌陷风险评估问题,中国地质科学院岩溶地质研究所塌陷项目组结合多年岩溶塌陷研究的经验,研制开发了基于GIS技术的岩溶塌陷灾害管理与风险评估系统(GMRS).本文以水城盆地为例,全面介绍运用GMRS进行岩溶塌陷风险评估的内容、方法和步骤,最后,对风险评估的结果作了详细讨论. 相似文献
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多年冻土区斜坡稳定性研究综述 总被引：1，自引：0，他引：1
全球变暖、极端天气频发,引发的地质灾害对自然生态环境和人类生产生活造成了很大的影响。尤其对气候变化较为敏感的高温（年平均地温>-1 °C）和高含冰量多年冻土区,气候变暖以及人类活动导致的冻融地质灾害日益频繁。冻土退化条件下,土体结构和物理力学性质发生改变,黏聚力和抗剪强度降低,造成多年冻土区斜坡发生滑坡、崩塌、泥流等灾害。斜坡失稳加剧了多年冻土区脆弱生态环境的恶化,同时对建（构）筑物安全运营产生威胁。与非冻土区相比,多年冻土区斜坡稳定性研究主要针对高含冰量斜坡段,斜坡失稳模式主要以热融滑塌和活动层滑脱为主。热融滑塌由斜坡段地下冰暴露融化引起,而活动层滑脱产生的原因是冻土融化导致土体孔隙水压力过大,形成的超孔隙水压力降低了土体强度,造成斜坡失稳。此外,多年冻土区斜坡失稳模式还包括融冻泥流、崩塌以及蠕变滑坡等。通过综述近期多年冻土区斜坡稳定性研究进展,概括了多年冻土区斜坡失稳的模式、特征、影响因素、失稳机理、分析方法及防治措施等,并对未来多年冻土区斜坡失稳的研究重点提出建议。 相似文献
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Girish Ch. Kothyari P. D. Pant Khayingshing Luirei 《Journal of the Geological Society of India》2012,80(1):101-110
Main Boundary Thrust (MBT) zone is constituted of some of the landslide prone areas in southeastern part of Kumaun Sub-Himalaya. Role of landslides as natural hazard and hill slope modifying agent is well documented from various part of Himalayan region and southern hills of Kumaun particularly in the MBT zone, which are susceptible to various type of mass movement. The rocks making up the slopes has been put to a number of brittle deformation phases during the movement along the MBT, and are traversed by number of joint sets. In the open slope these intersecting joint sets forms wedges and are the most favorable site for initiation of rockfalls and other types of landslides. Landslides are taking place primarily due to high angle slopes, formation of structural wedges along the free steep slopes, sheared nature of the rocks due to proximity to the MBT and neotectonic activities along the MBT and other transverse faults. Wedge failure is a common type of landslides in rock slopes characterized by multiple joints and acts as sliding planes for the failed blocks. Field observations and wedge failure analysis indicates most of the landslides taking place in MBT zone of Kumaun Sub-Himalaya are joint controlled. Safety Factor analysis suggests MBT zone of Kumaun Sub-Himalayan region is prone to landslides and related mass movements. This zone is also neotectonically active as indicated by various geomorphic signatures such as structurally controlled drainage pattern, offsetting of fan by MBT and formation of number of small lakes. 相似文献
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《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》1999,24(10):925-934
Detailed geomorphological mapping carried out in 5 sample areas in the North of Lisbon Region allowed us to collect a set of geological and geomorphological data and to correlate them with the spatial occurrence of landslide. A total of 597 slope movements were identified in a total area of 61.7 km2, which represents about 10 landslides per km2.The main landslide conditioning factors are: lithology and geological structure, slope angle and slope morphology, land use, presence of old landslides, and human activity.The highest landslide density occurs in Cretaceous marls and marly limestones, but the largest movements are in Jurassic clays, marls and limestones.The landslide density is higher on slopes with gradients above 20 °, but the largest unstable area is found on slopes of 10 ° to 15 °, thus reflecting the presence of the biggest slope movements. There is a correlation between landslides and topographical concavities, a fact that can be interpreted as reflecting the significance of the hydrological regime in slope instability.Concerning land use, the highest density of landslides is found on slopes covered with shrub and undergrowth vegetation.About 26% of the total number of landslides are reactivation events. The presence of old landslides is particularly important in the occurrence of translational slides and complex and composite slope movements.20% of the landslide events were conditioned by anthropomorphic activity. Human's intervention manifests itself in ill-consolidated fills, cuts in potentially unstable slopes and, in a few cases, in the changing of river channels.Most slope movements in the study area exhibit a clear climatic signal. The analysis of rainfall distribution in periods of recognised slope instability allows the distinction of three situations: 1) moderate intensity rainfall episodes, responsible for minor slope movements on the bank of rivers and shallow translational slides, particularly in artificial trenches; 2) high intensity rainfall episodes, originating flash floods and most landslides triggered by bank erosion; 3) long-lasting rainfall periods, responsible for the rise of the groundwater table and triggering of landslides with deeper slip surfaces. 相似文献
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根据地质环境背景资料和近350个地质灾害点和数十个水土流失区的数据库对广东沿海陆地表层地质灾害进行了综合分析和统计分析。结果表明，地质灾害的主要控制因素可分为三大类：地质环境因素、气候气象因素和人类活动因素，其中地质环境因素又可分为构造不稳定因素、斜坡不稳定因素和地面不稳定因素。指出，在广东沿海地区，除了地震灾害外，陆地表层地质灾害的主控因素是气候气象因素和人类活动因素，这是与山区以地质环境因素(尤其是内动力作用)为主是不相同的。降雨强度和时间、台风雨和风暴潮以及人类活动等对边坡和植被的改造是在沿海地区现有的地质环境背景下地质灾害多发的主要动力源。 相似文献
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Landslides triggered by slipping-fault-generated earthquake on a plateau: an example of the 14 April 2010, Ms 7.1, Yushu, China earthquake 总被引：3，自引：1，他引：2
On 14 April 2010 at 07:49 (Beijing time), a catastrophic earthquake with Ms 7.1 struck Yushu County, Qinghai Province, China. A total of 2,036 landslides were interpreted from aerial photographs and satellite images, verified by selected field checking. These landslides cover about a total area of 1.194 km2. The characteristics and failure mechanisms of these landslides are presented in this paper. The spatial distribution of the landslides is evidently strongly controlled by the locations of the main co-seismic surface fault ruptures. The landslides commonly occurred close together. Most of the landslides are small; there were only 275 individual landslide (13.5 % of the total number) surface areas larger than 1,000 m2. The landslides are of various types. They are mainly shallow, disrupted landslides, but also include rock falls, deep-seated landslides, liquefaction-induced landslides, and compound landslides. Four types of factors are identified as contributing to failure along with the strong ground shaking: natural excavation of the toes of slopes, which mean erosion of the base of the slope, surface water infiltration into slopes, co-seismic fault slipping at landslide sites, and delayed occurrence of landslides due to snow melt or rainfall infiltration at sites where slopes were weakened by the co-seismic ground shaking. To analyze the spatial distribution of the landslides, the landslide area percentage (LAP) and landslide number density (LND) were compared with peak ground acceleration (PGA), distance from co-seismic main surface fault ruptures, elevation, slope gradient, slope aspect, and lithology. The results show landslide occurrence is strongly controlled by proximity to the main surface fault ruptures, with most landslides occurring within 2.5 km of such ruptures. There is no evident correlation between landslide occurrences and PGA. Both LAP and LND have strongly positive correlations with slope gradient, and additionally, sites at elevations between 3,800 and 4,000 m are relatively susceptible to landslide occurrence; as are slopes with northeast, east, and southeast slope aspects. Q4 al-pl, N, and T3 kn 1 have more concentrated landslide activity than others. This paper provides a detailed inventory map of landslides triggered by the 2010 Yushu earthquake for future seismic landslide hazard analysis and also provides a study case of characteristics, failure mechanisms, and spatial distribution of landslides triggered by slipping-fault generated earthquake on a plateau. 相似文献
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High incidences of slope movement are observed throughout Cuyahoga River watershed in northeast Ohio, USA. The major type of slope failure involves rotational movement in steep stream walls where erosion of the banks creates over-steepened slopes. The occurrence of landslides in the area depends on a complex interaction of natural as well as human induced factors, including: rock and soil strength, slope geometry, permeability, precipitation, presence of old landslides, proximity to streams and flood-prone areas, land use patterns, excavation of lower slopes and/or increasing the load on upper slopes, alteration of surface and subsurface drainage. These factors were used to evaluate the landslide-induced hazard in Cuyahoga River watershed using logistic regression analysis, and a landslide susceptibility map was produced in ArcGIS. The map classified land into four categories of landslide susceptibility: low, moderate, high, and very high. The susceptibility map was validated using known landslide locations within the watershed area. The landslide susceptibility map produced by the logistic regression model can be efficiently used to monitor potential landslide-related problems, and, in turn, can help to reduce hazards associated with landslides. 相似文献
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汶川8级地震地质灾害的类型及实例 总被引：11，自引：2，他引：9
龙门山地区活动断裂右旋斜冲运动与汶川8级强烈地震存在成因联系。汶川8级地震造成了惨重的人员伤亡和巨大的财产损失,地震地质灾害主要类型有地震灾害、地震触发地质灾害和地震引发地质灾害隐患。严重地震灾害包括房屋倒塌与部分坍塌、房屋平移、房屋倾斜变形、墙体破裂与结构破坏、桥梁垮塌等。地震触发严重地质灾害包括山体滑坡、山体滑塌、岩块崩塌,局部产生泥石流与沙土液化。地震引发地质灾害隐患包括潜在滑坡、不稳定边坡与滑塌隐患、危岩体与崩塌隐患及泥石流灾害隐患。地震地质灾害分布与活动断层存在密切关系,沿北川映秀断裂地震地质灾害最为严重,沿汉旺漩口断裂、茂县汶川断裂、青川断裂地震地质灾害也比较严重。在活动断裂之间相对稳定地块远离活动断裂超过3~5 km,地震灾害和地震触发地质灾害显著减轻。 相似文献
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黄土边坡的变形破坏多发生于降雨期间,由此也造成了大量的损失。为减小降雨诱发黄土滑坡的影响,开展降雨型滑坡现场实验研究,具有现实意义。本文选取泾阳一天然黄土边坡为研究对象,利用自行设计的模拟降雨系统,设计并进行了3组不同雨强下的大型黄土边坡人工模拟降雨试验,旨在研究不同雨强条件下天然黄土边坡的入渗规律及变形破坏模式。通过对边坡内埋设的土壤水分传感仪、土压力盒和张力计管的读数变化及试验现象进行分析,进而得出降雨条件下大型黄土边坡现场试验的变形破坏规律,总结出该类边坡的水分入渗规律和变形破坏模式。试验结果表明,边坡入渗呈现一定的规律:降雨条件下,坡肩入渗深度和速率最大,坡脚次之,坡面最小;同时,降雨强度越大,雨水入渗速率越快,入渗时间越长,边坡相同位置处体积含水率和土压力增大幅度越大,基质吸力减小的幅度越大。降雨条件下天然黄土边坡的变形破坏模式为:坡肩侵蚀及侵蚀扩展→坡面裂隙形成扩展→坡肩裂隙形成扩展→局部滑塌;若继续降雨,则坡肩局部裂隙逐渐贯通进而形成滑面,最终导致滑坡发生。 相似文献
19.
基于GIS的滑坡地质灾害地貌因素分析 总被引：7，自引：1，他引：6
基于ArcGIS平台, 利用SRTM-DEM数据资料, 选择青藏高原东缘及四川盆地为研究区, 提取了区内地形起伏度和坡度等地貌参数, 统计了区内2319个滑坡点的高程, 初步建立了地形地貌与滑坡灾害点分布之间的对应关系。结果表明, 研究区滑坡灾害点及其高程分布具有明显的区域规律性, 滑坡灾害点发生的高程为400~800m和1400~2000m, 这两个区间占研究区所有滑坡总数的40%和28%;滑坡所对应的地形起伏度主要在300~600m, 占研究区所有滑坡总数的48.68%;滑坡灾害发生的地形坡度为10°~25°, 占研究区所有滑坡总数的44.70%。研究发现, 这些地区对应的地貌类型主要是深切的"V"型河谷和山谷地貌。此外, 从断裂活动等方面分析了滑坡形成的动力机制。 相似文献