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1.
凤城地区是我省地质灾害严重的地区之一,其特点是灾域广、发生频、灾情重、灾史长。尤其是泥石流灾害,已经引起了各级政府和科研产业部门的高度重视。灾害评价已成为帮助有关部门决策的重要途径之一。从凤城地区泥石流灾害评价中,可找出滑坡泥石流形成的基本条件、诱发动力  相似文献   

2.
以盐源县的泥石流发生为例,研究了凉山地区出现局地强降雨引发的中型泥石流灾害的气象成因。运用天气学方法,使用NCEP再分析资料以及卫星云图和雷达回波等遥感资料,从环流形势、强对流不稳定、卫星云图和雷达回波图像演变特征,研究了台风登陆时凉山地区强降雨引起泥石流灾害形成的气象成因,并讨论了应用多普勒雷达回波对局地强降水及泥石流灾害短时临近监测和预报预警的思路。  相似文献   

3.
本文探讨了西宁地区黄土重矿物的特征。并结合粒度、石英砂表面结构特征分析结果,提出西宁地区黄土主要来源于青藏高原内部。  相似文献   

4.
贡嘎山东坡雅家埂河特大型泥石流动力学特征   总被引:1,自引:0,他引:1  
对2005年8月11日贡嘎山东坡雅家埂河特大型泥石流运动过程进行了描述,并采用现场实地勘查等手段,定量计算泥石流流速和流量等动力学特征,还运用得到的流量反演泥石流运动过程,从而得到雅家埂河特大型泥石流的形成机理。结果表明:雅家埂河特大型泥石流的形成与降雨有直接关系;雅家埂河支沟泥石流的群发性造成主河泥石流规模巨大;经对雅家埂河流域泥石流形成、发生的历史分析,推断出该流域泥石流存在18~21年的暴发周期;雅家埂河松散物源充足,降雨与水源丰富,地形地貌陡峭,极易再次发生规模较大的泥石流。  相似文献   

5.
全省现状 河南省是一个泥石流多发地区,全省有泥石流沟475条,受地形和地质条件制约,泥石流多发生在中低山区及黄土丘陵地区,集中分布在伏牛山、小秦岭、太行山、豫西黄土地区.按地貌条件划分,沟谷型和河谷型泥石流沟400条.  相似文献   

6.
栖霞市生木树泥石流隐患点为烟台市471处地质灾害隐患点其中1处,曾于1979年7月因暴雨引发泥石流灾害,给当地村民造成严重经济损失。以该泥石流沟流域作为研究区,并以区内泥石流发育的自然环境、基本特征及形成泥石流的地质条件、物源条件和水源条件等勘察成果为基础,综合分析区内泥石流发育特征、类型、形成机理、引发因素,并选取相关参数对泥石流基本特征值进行计算,为同类型泥石流的防治提供科学依据。综合研究确定区内泥石流易发程度为轻度易发,现阶段泥石流沟发展阶段为发展期,泥石流灾害趋于相对稳定,但一旦遭遇暴雨至特大暴雨,可能会再次引发泥石流地质灾害。  相似文献   

7.
滑坡和泥石流是陕南山地成灾的主要物理地质现象。本文根据野外调查资料和前人研究成果,从地质、地貌、水文工程地质特征、水文气象、人为因素诸方面,简要的分析了陕南山地滑坡、泥石流形成条件、区域分布规律滑坡对泥石流形成的影响和滑坡转化成泥石流的辩证关系。  相似文献   

8.
干江沟位于栾川县城西部伏牛山北麓的石庙镇常门村,该沟道储存大量松散物质,中上游有尾矿库,尾矿库溃坝引发沟道泥石流,损失惨重。本文从降水条件、洪水流速分析入手,研究沟道颗粒启动形成泥石流的临界速度,从而判断洪水为本次泥石流形成创造了有利条件,尾矿库溃坝是决定条件。尾矿库溃决后,洪水携带矿粉形成巨大洪流以较快的流速拖拽揭起沟床砂石及冲垮沟岸松散堆积物混合形成泥石流。通过泥石流形成机理和溃坝分析,提出预防方案,为地灾减灾提供地质依据。  相似文献   

9.
全省现状河南省是一个泥石流多发地区,全省有泥石流沟475条,受地形和地质条件制约,泥石流多发生在中低山区及黄土丘陵地区,集中分布在伏牛山、小  相似文献   

10.
浙江由于其独特的地理位置,复杂的地质、地形和气候背景,是我国降雨引发滑坡、泥石流等突发地质灾害最频繁的地区之一。浙江经济最发达,人口稠密,极易出现小滑坡(泥石流)大灾害情况。为科学防范降雨引发的滑坡、泥石流等地质灾害,最大可能地减少人员伤亡,我省建立的突发地质灾害预警预报系统从2003年7月开始投入运行,至今已进入第8个年头,已初步形成了预警预报系统与群测群防结合的防灾体系,并在实际应用中取得了显著的减灾成效。  相似文献   

11.
牛眠沟流域泥石流形成条件、发展趋势及其防治探讨   总被引:1,自引:0,他引:1  
汶川地震使牛眠沟流域变成了一个多泥石流灾害的区域,到目前为止,已经发生7次大规模泥石流灾害。经研究,该流域诱发泥石流灾害的3个基本条件非常发育,而目前正处于发展阶段,在震后5~10年内的雨季,极易发生危害性较大、冲击力较强的大规模降雨型泥石流。如果考虑直接利用主沟内沉积的泥石流堆积物,在主沟堆积区的中上游左右两侧修建约为沟宽一半的交替式拦挡土石坝、在中下游修建与沟宽大致相等的拦挡土石坝及在相邻两坝间修建与沟向相对且具有一定坡度斜坡的土木防治工程,可实现消能与耗能双重目的。  相似文献   

12.
陕西商洛及河南卢氏、栾川地区上元古界和下古生界地层中发育有滑塌堆积物,其主要类型包括岩崩、滑动、滑塌和沉积物重力流,其中后者主要见到碎屑流、颗粒流和浊流沉积。它们多从下到上构成了由粗到细由浅水到深水的退积序列,呈海相扇三角洲沉积在晚元古代冰川边缘及早古生代碳酸盐台地边缘的两种大陆斜坡上,其沉积特征反映了中朝板块南缘从晋宁期到早加里东期呈强烈抗张断陷的大陆边缘环境。  相似文献   

13.
宏观上论述了我国西部道路交通开发中地质环境基本特点、主要工程地质问题及工程可行性,并着重指出,地形复杂、地壳强活动、滑坡泥石流、冻土和风沙等灾害构成了交通开发中施工、养护的突出问题,部分干旱区水源匮乏矛盾尤为突出,但工程地质环境仍具可选择的条件。  相似文献   

14.
Taiwan has disadvantageous conditions for sediment-related disasters such as debris flows. The construction of engineering structures is an effective strategy for reducing debris flow disasters. However, it is impossible to construct engineering structures in all debris flow areas in a short period. Therefore, the government aims to gradually develop non-structural preventive strategies, including evacuation planning, debris flow disaster emergency action system, disaster resistant community program, recruitment of debris flow professional volunteers, debris flow warning systems, and land management strategies, to mitigate disasters and secure the safety of residents. This review describes the processes and effects of recent debris flow non-structural preventive strategies in Taiwan. The average number of casualties prior to the year 2000 was far higher than the corresponding number after 2000 because debris flow evacuation drills have been promoted since 2000 and the debris flow disaster emergency action system has been progressively improved since 2002. Furthermore, the changes in risks caused by debris flow disasters before and after the implementation of non-structural preventive strategies were used to explain the effectiveness of these strategies at the community level. The results showed that software-based non-structural preventive strategies can effectively reduce the casualties caused by debris flows at both the national and community levels.  相似文献   

15.
《山地科学学报》2020,17(1):156-172
Loose deposits, rainfall and topography are three key factors that triggering debris flows.However, few studies have investigated the effects of loose deposits on the whole debris flow process.On June 28, 2012, a catastrophic debris flow occurred in the Aizi Valley, resulting in 40 deaths.The Aizi Valley is located in the Lower Jinsha River,southwestern Sichuan Province, China. The Aizi Valley debris flow has been selected as a case for addressing loose deposits effects on the whole debris flow process through remote sensing, field investigation and field experiments. Remote sensing interpretation and laboratory experiments were used to obtain the distribution and characteristics of the loose deposits, respectively. A field experiment was conducted to explore the mechanics of slope debris flows, and another field investigation was conducted to obtain the processes of debris flow formation, movement and amplification. The results showed that loose deposits preparation, slope debris flow initiation,gully debris flow confluence and valley debris flow amplification were dominated by the loose deposits.Antecedent droughts and earthquake activities may have increased the potential for loose soil sources in the Aizi Valley, which laid the foundation for debris flow formation. Slope debris flow initiated under rainfall, and the increase in the water content as well as the pore water pressure of the loose deposits were the key factors affecting slope failure. The nine gully debris flows converged in the valley, and the peak discharge was amplified 3.3 times due to a blockage and outburst caused by a large boulder. The results may help in predicting and assessing regional debris flows in dry-hot and seismic-prone areas based on loose deposits, especially considering large boulders.  相似文献   

16.
黑马渠沟流域滑坡较发育 ,密度达 9.4个 /km2 ,目前 ,滑坡及滑坡型泥石流灾害已成为制约卢氏县城社会和经济发展的因素之一。本文从地质、地貌、气象、水文等环境条件入手 ,分析了滑坡的分布规律及其成因 ,并针对滑坡的类型特征及危害方式 ,提出了相应的减灾对策  相似文献   

17.
柴达木盆地东北缘地质灾害及防治   总被引:1,自引:0,他引:1  
青海省柴达木盆地东北缘地貌类型复杂,新构造运动强烈,由各种内外应力造成的地质灾害具有类多、发生频繁等现象,集中反映在土地荒漠化、水土流失、草场退化、湖泊萎缩、地震、泥石流及滑坡等面,人类生存环境日趋恶劣。通过对该区各类地质灾害及生态环境现状进行评述,提出了治理建议。  相似文献   

18.
A probabilistic view of debris flow   总被引:1,自引:1,他引:0  
  相似文献   

19.
Techniques of gully-specific debris flow hazard assessment developed in four periods since the end of the1980s have been discussed in the present paper. The improvement for the empirical assessment method is the sectional-ized function transformation for the factor value, rather than the classified logical transformation. The theoretical equationof the gully-specific debris flow hazard is expressed as the definite integral of an exponential function and its numericalsolution is expressed by the Poisson Limit Equation. Current methods for assessment of debris flow hazard in China arestill valid and practical. The further work should be put on the study of the reliability (or uncertainty) of the techniques.For the future, we should give a high priority to the relationship between debris flow magnitude and its frequency of occur-rence, make more developments of prediction model on debris flow magnitude, so as to finally reach the goal of assessingthe hazard of debris flow by theoretical model, and realize both actuality assessment and prediction appraisal of debris flow.  相似文献   

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