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1.
新疆干旱区地质灾害研究   总被引:1,自引:0,他引:1  
本文详尽叙述了新疆干旱区突发性较强的地震、崩塌、滑坡、泥石流灾害以及具牵延性特点的土地沙漠化、盐渍化、水土流失等为主要类型地质灾害的活动规律和时空分布特征;根据灾害强度,进行了灾害等级区域划分;结合新疆干旱区特点,提出了减轻新疆地质灾害的主要对策和措施。  相似文献   

2.
南海西部灾害性地质研究   总被引:5,自引:0,他引:5  
灾害地质学(hazard geology)是研究对海底工程,特别是海洋石油工程能够产生直接危害,或具有潜在性危害的地质因素的特征及分布规律的科学。在过去几十年的海上石油开发中,由于事先未能对灾害性地质进行详细调查而造成重大损失的事件不乏其例。1973年3月,墨西哥湾一钻井平台,因浅层天然气喷发引起火灾,数千万美元的仪器设备毁于一旦。1977年南海莺歌海盆地作业的一架自升式钻井平台,在水深75m处插桩时,由于埋藏古河道的影响,地层分布不连续,两只柱腿插在古河岸上,至海底以下3m即稳定,另一只桩腿落入古河床,插入21m尚不稳定,致使钻井平台倾斜,后被迫移位才免遭于害。灾害性地质问题的研究已成为海洋石油和天然气开发成败的关键问题之一,因而引起了国内外有关部门的极大重视。1985-1987年,中国科学院海洋研究所受南海西部石油公司的委托,对珠江口以西至北部湾东部的广大海域,进行了大规模的灾害性地质、工程地质的普查及井位调査。调查中先后使用了“科学一号”科学考察船和“南海502”、“南海503”等工程物探及工程地质调查船,在海上进行了七千余公里的综合性工程物探测量,为研究调查区灾害性地质问题积累了丰富的资料。  相似文献   

3.
南黄海灾害性地质研究   总被引:2,自引:0,他引:2  
本文研完了南黄海10种灾害地质因素的性质、危害性及分布,对其进行了分类,在此基础上对本区之灾害地质进行了区划和评价。  相似文献   

4.
黄河口有着我国典型的新生湿地生态系统,生态环境非常脆弱,极易受到陆源和海洋污染事故的影响。本文针对黄河口附近海上油田的开发和运输带来的潜在溢油风险,结合溢油污染概率模型以及河口的生态脆弱性,对黄河口湿地潜在溢油污染风险进行评估。在河口水动力模拟的基础上,采用随机情景模拟法选取300种风和潮流组合作为溢油模拟的强迫条件,分别模拟溢油后72 h和720 h的污染结果,并统计黄河口湿地受溢油污染影响的最大概率和最短时间,采用环境敏感指数表征湿地对溢油污染的敏感程度、危害后果指数量化表征其危害程度及风险矩阵量化风险高低。结果表明黄河口国家公园受潜在溢油污染概率较大,危害后果指数值为29,处于较高危害等级,属于中风险区;河口岸线受潜在溢油污染概率较小,危害后果指数值均小于1,溢油危害后果低,属于低风险区。  相似文献   

5.
Bathing beaches are usually the first to suffer disasters when tsunamis occur, owing to their proximity to the sea. Several large seismic fault zones are located off the coast of China. The impact of each tsunami scenario on Chinese bathing beaches is different. In this study, numerical models of the worst tsunami scenarios associated with seismic fault zones were considered to assess the tsunami hazard of bathing beaches in China. Numerical results show that tsunami waves from the Pacific Ocean could affect the East China Sea coast through gaps between the Ryukyu Islands. The Zhejiang and Shanghai coasts would be threatened by a tsunami from Ryukyu Trench, and the coasts of Hainan and Guangdong provinces would be threatened by a tsunami from the Manila Trench. The tsunami hazard associated with the Philippine Trench scenario needs particular attention. Owing to China’s offshore topography, the sequential order of tsunami arrival times to coastal provinces in several tsunami scenarios is almost the same. According to the tsunami hazard analysis results, Yalongwan Beach and eight other bathing beaches are at the highest hazard level. A high-resolution numerical calculation model was established to analyze the tsunami physical characteristics for the high-risk bathing beaches. To explore mitigating effects of a tsunami disaster, this study simulated tsunami propagation with the addition of seawalls. The experimental results show that the tsunami prevention seawalls constructed in an appropriate shallow water location have some effect on reducing tsunami hazard. Seawalls separated by a certain distance work even better. The analysis results can provide a scientific reference for subsequent preventive measures such as facility construction and evacuation.  相似文献   

6.
山东沿海及近海地区主要地质灾害类型分析   总被引:3,自引:0,他引:3  
山东沿海与近海地区发育有多种地质灾害.通过对该地区存在的主要地质灾害进行系统的野外调查、统计与分析,编绘了研究区及邻域的地质灾害分布图,总结了各种地质灾害的空间发育特点.在成因分析的基础上,将研究区内的地质灾害划分为地震、地面变形、边坡灾害、流体灾害、水土质变异、气相灾害、不稳定沉积和其它地质灾害因素8类,并进一步细分为33种.作者从地质灾害的形成动力、成生关系、成灾过程、成灾关联性、成灾可控性及其危害性出发,阐述了各种地质灾害的属性特征.为防灾减灾提供了决策依据.  相似文献   

7.
珠江口海岛及海域地质环境与灾害初探   总被引:4,自引:0,他引:4  
珠江口海岛及其邻近海域是华南沿海地质灾害类型较齐全的地区之一,主要有活动断裂、地震、地裂缝、软土、风沙、滑坡、崩塌、地面沉降和海平面上升等。珠江口海岸主要发育弱活动和微活动断裂,活动断裂和断块构造的运动和调整是产生地震活动的主要因素。海平面上升已成为当今世界关注的环境恶化和未来50a内产生严重威胁的灾害。风沙作用和软土地基主要分布于珠江口海岛海岸带及近岸岛屿。本区的地质灾害以内动力类型为主。  相似文献   

8.
文章于杭州湾南岸潮滩布设3个采样断面并采集沉积物样本,采用地质累积指数法和潜在生态危害指数法评价重金属污染状况及其生态风险。研究结果表明:沉积物基本为粗粉砂和细砂,由海向陆粒径逐渐变细且分选性逐渐转差;所有站位重金属含量均值从高到低依次为Pb、Zn、Cu、Cr、Cd和Hg,断面重金属含量从高到低依次为高潮滩、中潮滩和低潮滩,Cu、Hg和Pb的空间分布差异较大;本次采样调查结果与邻近区域数据和同区域历史数据相比有所不同;根据地质累积指数评价结果,Cu、Pb和Zn有不同程度的污染;根据污染指数和潜在生态危害指数评价结果,Zn、Cd和Cr与地质累积指数评价结果区别较大,研究区重金属总体污染程度为低度和中度,除Cd外其他重金属处于低生态危害水平,研究区重金属总体生态危害为低度。调查和研究成果可为分析区域重金属环境影响和制定污染控制对策提供科学依据。  相似文献   

9.
中国沿岸有居民海岛受台风影响极大,综合考虑台风对有居民海岛的各方面影响因素,基于自然灾害风险理论从致灾因素、承灾体脆弱性和防灾减灾能力3个方面选取29个指标,建立有居民海岛台风灾害评估指标体系框架,采用层次分析法确定各个指标的权重,并分析指标体系的特点和应用。通过指标权重的排序明确了影响有居民海岛台风灾害的关键因子,为有居民海岛台风灾害防御奠定了理论基础。  相似文献   

10.
渤海海域地震海啸灾害概率性风险评估   总被引:1,自引:0,他引:1  
渤海作为我国地震活动性最为活跃的近海,其地震海啸风险不可忽视。本文应用概率性海啸风险评估方法对渤海周边区域的海啸风险进行评估。根据历史地震目录建立了渤海区域的震级-频率关系,基于蒙特卡洛算法随机生成了一套10万年的地震目录,最终通过对地震事件的海啸数值模拟及最大波幅的统计分析给出了环渤海区域典型重现期的最大波幅分布以及重点城市的海啸波幅曲线。评估结果表明,渤海地区海啸风险主要集中在渤海湾和莱州湾周边,波幅可达到1~3 m,辽东湾地区海啸风险较低。  相似文献   

11.
An unstable rock volume of more than 50 million m3 has been detected in the Åkerneset rock slope in the narrow fjord, Storfjorden, Møre & Romsdal County, Western Norway. If large portions of the volume are released as a whole, the rockslide will generate a tsunami that may be devastating to several settlements and numerous visiting tourists along the fjord. The threat is analysed by a multidisciplinary approach spanning from rock-slope stability via rockslide and wave mechanics to hazard zoning and risk assessment.The rockslide tsunami hazard and the tsunami early-warning system related to the two unstable rock slopes at Åkerneset and Hegguraksla in the complex fjord system are managed by Åknes/Tafjord Beredskap IKS (previously the Åknes/Tafjord project). The present paper focuses on the tsunami analyses performed for this company to better understand the effects of rockslide-generated tsunamis from Åkerneset and Hegguraksla. Two- and three-dimensional site-specific laboratory experiments are conducted to study the generation, propagation, and run-up of the wave for several potential rockslide scenarios from Åkerneset. Furthermore, the two models GloBouss and DpWaves are applied for numerical simulations of the generation/propagation phase and a third model MOST is applied for numerical simulations of the near-shore propagation and inundation of the wave in selected locations. Strong emphasis is put on verification, validation, and sensitivity of the numerical models. The best match between the numerical simulations and the laboratory experiments is found for the larger scenarios with the linear dispersive solution for the propagation phase; the corresponding calculated run-up values are remarkably similar to the ones observed during the laboratory experiments.During the risk assessment it was found that the rockslide tsunami hazard (probability of impact) is higher than accepted by the Norwegian Planning and Building Act. This should at that time prevent any further development in all the exposed areas of the entire fjord system. The Act is today altered to open for specified further development in the various hazard zones. The results of the tsunami analyses are applied in risk management in terms of hazard map production and land-use planning. Two failure scenarios for each of the two unstable rock slopes are designed for the hazard zoning. The larger and less probable scenarios (1 in 5000 years) are applied for evacuation zones and routes, while the smaller and more probable scenarios (larger than 1 in 1000 years) are applied for location and design of less critical facilities accepted in the inundation zone.  相似文献   

12.
Coastal hazards are in the interface of human activities with natural coastal processes. The conflicts arising from this relationship require new approaches suitable for coastal management that consider the dynamic of coastal areas. A method to assess hazard in rock cliffs is presented, combining cliff evolution forcing mechanisms along with protection factors, according to a weighted factors system. This method provides a rapid evaluation of vulnerability for cliffed areas, supporting coastal management and hazard mitigation. The method was applied to the rocky cliffs of the densely populated coastal zone between Galé and Olhos de Água (Southern Portugal), where high and very high hazard values were found to be dominant. A method validation was made using the vulnerability areas and the recorded mass movements over a 45 year period in the same area.  相似文献   

13.
辽东湾北部浅海区海洋工程地质特征   总被引:2,自引:0,他引:2  
通过对浅地层剖面仪、侧扫声纳和海底取样等实测资料的详细分析,揭示了辽东湾北部浅海区的自然地质状况和复杂的海洋工程地质特征。该海区海底地形地貌较为复杂,存在海底冲刷深槽、埋藏古河道、浅层气、潮流沙脊与潮沟、埋藏古陡坡、软弱土层及可能的砂土液化层等潜在灾害地质因素,对海上构筑物存在直接或潜在的危险性,应引起高度重视。  相似文献   

14.
Coastal erosion and flooding are major threats to coastal dwellers, and the situation is predicted to worsen as a result of the impacts of climate change and associated sea level rise. In order to identify the level of vulnerability of various sections of Ghana's coastline for planning and future hazard management, a coastal vulnerability index approach was adopted for the creation of the relative vulnerability map. The coastal vulnerability variables used include geomorphology, coastal elevation, geology, local subsidence, sea level rise, shoreline change rates, mean tidal range, mean wave height and population density of the coastal areas. Risk factors were assigned to the various variables, and all the factors were combined to calculate the coastal vulnerability for the coastal front of each administrative district along the coast. The outcome was used to produce a vulnerability index map of coastal districts in Ghana. The results revealed that parts of the central coast and the eastern coasts of Ghana were the most vulnerable. It was identified that about 50% of the 540km shoreline of Ghana is vulnerable. This assessment will facilitate the long-term adaptation planning and hazard mitigation to inform the management of Ghana's coast.  相似文献   

15.
影响东海海底管道安全的灾害因素   总被引:1,自引:0,他引:1  
通过多年的海底管道检测成果,分析了东海海区对管道路由存在威胁的灾害因素,认为可以分为人类活动、海流冲刷、浅部地质灾害和砂质底质等;重点探讨了拖痕、海流冲刷、浅层气和砂土液化等灾害因素的致灾机理和致灾结果,目的是加深对这些灾害的认识,以期在今后的检测中能够及时发现存在的安全隐患,并能采取相应的防范措施,确保海底管道的安全运行。  相似文献   

16.
随着海洋资源的开发与滨岸工程的建设,越来越多地遇到海洋地质灾害的影响与危害。为了避免并降低海洋地质灾害的影响程度,应开展海洋灾害地质与工程地质调查。二十多年来的实践经验表明,若采用以高分辨率地震为主,配合浅地层剖面、旁侧声纳、测深及磁力测量等综合浅层物探技术,对于了解海洋地质灾害因素与海底浅部工程地质特性等方面都能取得良好的效果,这是一种既经济又较快速地提供成果资料的好方法。  相似文献   

17.
应急管理是海洋灾害风险管理和防灾减灾工作的重要内容。应急管理是一个综合复杂的系统,需要各组成部门的协调一致。文章以连江海洋减灾综合示范区为例,详细分析了海洋灾害应急管理体系的总体构成以及完善海洋综合防灾减灾应急预案体系的重要作用。通过连江海域海洋减灾综合示范区建设,进一步规范风暴潮和海浪灾害以及赤潮灾害应急处置流程,提升各级海洋综合减灾能力,为其他沿海地区开展海洋灾害综合示范区建设和海洋综合灾害应急管理体系的构建提供经验和参考。  相似文献   

18.
文章结合连江海洋减灾综合示范区的总体建设情况,重点分析海洋灾害监控防控系统的构建思路和成果应用,主要包括海洋在线监测系统、海洋灾害信息发布系统、海洋减灾综合应急标志系统和海洋减灾综合视频监控系统,为其他地区开展以沿海重点养殖区为重点保障目标的海洋减灾综合示范区建设提供借鉴和参考。  相似文献   

19.
The achievement progresses of investigation and studies on marine hazardous geology are summarized and presentsd in the late 20 century in China. The importance, research value and presentday studies of marine hazardous geology, a newly developing branch of geoscience, are well expatiated.Several often confused concepts and theories are explained and redefined here. The comment on the means of investigations, assessment of marine hazardous geology, as well as its evolution, innovation,existing questions and future tasks are also introduced and presented. The concepts of “hazard geology“,“geohazard“, “map of marine hazard geology“, “integrated evaluaton on seafloor stablity“ are respectively discussed, including their definition, research objects, methods and contents. The types and classification of marine hazardous geology, principles and methods of marine hazardous geology map compilation, the assessment methods and models of marine hazardous geology environment and seafloor stability and so on are also discussed.  相似文献   

20.
近十年来中国大陆沿海地区重大海洋灾害分析   总被引:4,自引:0,他引:4  
伴随中国海洋经济的发展,沿海重大海洋灾害已成为沿海地区可持续发展的重要影响因素。近十年来,中国沿海灾害直接经济损失数十亿元到数百亿元,并造成严重的人员伤亡。台风、温带气旋引起的风暴潮和海浪灾害是造成中国沿海重大海洋灾害的主要致灾因素。初步分析了近十年来重大海洋灾害和厄尔尼诺之间的关系,指出强厄尔尼诺年前后,多发生严重的海洋灾害,加强灾害预报和实施必要的减灾对策,对中国沿海的可持续发展具有重要意义。  相似文献   

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