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1.
拉丁美洲大地构造轮廓、成矿区带和成矿系列   总被引:1,自引:0,他引:1  
拉丁美洲是全世界矿产资源最丰富的地区之一。总结该地区的成矿地质背景、划分成矿区带、研究成矿系列将对进一步规划勘查和开发起到指导作用。在大地构造轮廓方面分成3个构造亚域,对次级构造单元的划分方案进行了探讨。在成矿区带划分方面,按5级成矿区带的划分方案,对一级成矿域和二级成矿省进行了划分,三级及其以下的成矿单元,对前人的划分方案作了扼要的比较。在成矿系列方面以大地构造演化为主导,以成矿作用和矿床类型为标志,将有内在成因联系的一系列矿床整合成一个成矿系列,并细分为成矿亚系列和成矿组合。  相似文献   

2.
《Atmósfera》2014,27(1):61-76
The Carbon Tracker system will play a major role in understanding CO2 sinks and sources, gas exchange between the atmosphere and oceans, and gas emissions from forest fres and fossil fuels in Latin America and the Caribbean. This paper discusses the trends in carbon fluxes in the biosphere and ocean, as well as emissions from forest fres and fossil fuel use in the above-mentioned region, using the Carbon Tracker (CT) system. From 2000 to 2009, the mean carbon fluxes for the biosphere, fossil fuel use, wildfires and the ocean in Latin America and the Caribbean were −0.03, 0.41, 0.296, −0.061 Pg C/yr, respectively, and −0.02, 0.117, 0.013, −0.003 Pg C/yr, respectively, in Mexico. The mean net carbon flux for Latin America and the Caribbean was 0.645 Pg C/yr, and 0.126 Pg C/yr for Mexico. The terrestrial sinks in Latin America and the Caribbean are dominated by the forest, agricultural, grass and shrub regions, as well as the Andes mountain range and the net surface-atmosphere fluxes including fossil fuel are dominant in regions around large cities in Mexico, Brazil, Chile, and areas undergoing deforestation along the Amazon River. The results confirm that forest fres are an important source of CO2 in Latin America and the Caribbean. In addition, we can confirm that policies encouraging the use of ethanol in light vehicles in Brazil have helped to decrease carbon emissions from fossil fuel, and assume the effects of the Proárbol program on carbon sinks from the biosphere and from fire emissions sources in Mexico. Based on this analysis, we are confident that the CT system will play a major role in Latin America and the Caribbean as a scientific tool to understand the uptake and release of CO2 from terrestrial ecosystems, fossil fuel use and the oceans, and for long-term monitoring of atmospheric CO2 concentrations.  相似文献   

3.
介绍拉丁美洲铝土矿资源概况、地质特征及成因类型。拉丁美洲铝土矿资源主要分在巴西、苏里南、牙买加、圭亚那、委内瑞拉等国家,储量为60.3×10~8t,占世界铝土矿总储量的21.54%。巴西为拉丁美洲最大的铝土矿生产国和出口国。拉丁美洲铝土矿成因类型主要为红土型和岩溶型2种,主要的铝土矿矿山有45座。牙买加岛弧、圭亚那地盾、中巴西地盾、圣弗朗西斯科地盾为4个铝土矿勘查开发潜力区。  相似文献   

4.
Ismail-Zadeh  Alik 《Natural Hazards》2022,111(2):2147-2154
Natural Hazards - Many nations face challenges in assessing, understanding, and responding to the time-dependent nature of disaster risk. Changes in the intensity of occurrences of extreme events...  相似文献   

5.
6.
地质灾害土地资源易损性评价定量探讨   总被引:3,自引:0,他引:3       下载免费PDF全文
地质灾害风险评估中对土地资源易损性考虑较少,作为自然资源的主要承灾体,土地资源应和人口和物质财富一样进行定量化研究。在地质灾害评价理论和土地资源价值理论的基础上,探讨了地质灾害风险评估中的土地资源易损性评估的技术方法。易损性的影响因素是灾害强度和土地资源承灾能力,承灾能力的影响因素是土地利用方式、土壤类型等,基于此,建立了数学模型进行易损性计算,核算了土地资源的经济价值、社会价值、生态价值,进行了综合易损性计算和土地资源易损性区划,并在西乡县进行了实例验证。  相似文献   

7.
The regionalization of urban natural disasters in China   总被引:1,自引:1,他引:0  
An integrated urbanization level (CL) index and an integrated natural disaster intensity (QC) index were developed on the basis of Disaster System Theory and China Natural Disaster Database for integrated urban disaster risk assessment. Integrated quantitative assessments of the urban socio-economic system and the intensity of hazards in China were carried out by the Model-Tupu (map series) and inter-feedback process using digital map technology. On the basis of this assessment, China can be regionalized into three regions, namely, coastal urban disaster region, eastern urban disaster region and western urban disaster region, 15 sub-regions and 22 units. These results can provide a scientific basis for determining a city’s disaster risk management and natural disaster relief regionalization in China.
Pei-jun ShiEmail:
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8.
9.
Natural hazards in Central Java Province,Indonesia: an overview   总被引:2,自引:0,他引:2  
Central Java Province, Indonesia, suffers from natural hazard processes such as land subsidence, coastal inundation, flood, volcanic eruption, earthquake, tsunami, and landslide. The occurrence of each kind of natural hazard is varied according to the intensity of geo-processes. It is necessary to learn from the historical record of coastal inundation, flood, volcanic eruption, earthquake, tsunami, and landslide hazards in Central Java Province to address issues of comprehensive hazard mitigation and management action. Through the understanding about the nature and spatial distribution of natural hazards, treatments can be done to reduce the risks. This paper presents the natural hazard phenomena in Central Java Province and provides critical information for hazard mitigation and reduction.  相似文献   

10.
C. N. Caviedes 《GeoJournal》1985,11(1):111-119
The exploitation of natural resources in Latin American countries has become one of the most controversial issues of contemporary development. Three positions arise: 1) a position that opens the development of natural resources to foreign priorities and capitals; 2) a position that opposes any kind of development if it is not conducted by the state, even if the state lacks the financial resources to do so; and 3) a position that sees advantages in negotiating the development of resources with external partnership but reserves for the state the determination of priorities and the leading role in the exploitation. The third position assumes the existence of a responsible government commited to safeguarding national interests. Unfortunately, this last assumption is not very operative with Latin American governments which seldom have standing policies concerning natural resources, which leaves them open to assaults from private national and international interests.Contrary to opposite views, it has been demonstrated that the development of natural resources brings about stimulation of regional economies and relocation of populations toward resource frontiers. Opposing the development of such areas of resources is to negate the concept of progress and to deepen chronic poverty.  相似文献   

11.
Traditional natural hazard researchers have failed to deal with hazard occurrences in Latin America in a comprehensive and coherent fashion because of their cultural bias and lack of knowledge about the regional implications of hazard conditions.The attempt is made in this paper to point out that some of the climatic hazards that beset South America, such as El Nino phenomenon on the coasts of Peru and Chile, the frosts in south-central Brazil, and the droughts of NE Brazil, are not isolated occurrences, but meteorological anomalies whose implications encompass not only the affected areas but also distant environments and economies.Systems analysis is utilized to prove that the oceanic-climatic El Nino phenomenon is genetically linked to global climatic anomalies and that the effects of such anomalies are felt in the ecological balance of the Pacific basin, of Africa, and of S Asia. Among their economic implications are shortages of anomal protein (from fish meal) and crop failures in Africa and the Soviet Union. Political consequences of hazardous conditions are also evident at hand of the 1971–73 climatic oscillations, of which El Nino was a symptom.In order to provide natural hazard research with a coherent theory, the cusp catastrophe theory of Thom and Zeeman is applied to the understanding of the conditions that lead to the onset of an oceanic-climatic El Nino occurrence. It is suggested that — considering that such a situation arises from interdependent ocean-atmosphere feedbacks — only under very special circumstances does this interplay lead to the sudden development of an El Nino condition. Catastrophe theory is not a deterministic theory but it considers the possibility of sudden change of states within a system.  相似文献   

12.
 Although British Columbia experiences many natural hazards, there is as yet no unified policy to promote natural hazard management in the province. The problem is not in the quantity and quality of geoscience assessment of natural hazards, but instead, it is suggested, in the isolation of that work from broader risk perspectives and in the lack of clarity of division of responsibilities between various levels of government. The example of recent changes in perception of the terrain stability problem illustrates how natural hazard problems are driven by social and political priorities rather than by geoscience priorities. Received: 22 November 1998 / Accepted: 22 November 1998  相似文献   

13.
The Bavarian Alps region is strongly affected by various natural hazards, mainly hydrological events (floods, debris flows), geomorphic/geological events (landslides, rock falls), and avalanches. Extraordinary floods, like in 2002 or in the summer of 2005 in south Bavaria, have again posed the question of the possible extent and frequency of recurrence of catastrophic events. To put risk assessment on a broader basis historical data about all kinds of past natural hazards were detected in the archives of local authorities and administrative offices for water management. More than 10,000 sources (written accounts, maps, and photographs) were collated in a database. The majority of this information reaches back to the middle of the 19th century. In addition, many documents referring to events dating back even as far as the middle age were found. The Historische Analyse von NaturGefahren (HANG, historical analysis of natural hazards) project at the University of Eichstaett mainly focuses on a small-scale examination of the data. Initial results of the data analysis show that most catastrophic events in the Bavarian Alps only affect parts of the area, but not the whole region. Therefore it is necessary to assess the risk potential on a local scale like valleys, the catchment areas of mountain streams, or even single streams. Firstly the presented data is aimed to help engineers in future planning of hazard-protection measures. Secondly the information can form a vital component to enhance our knowledge of hydrological and geomorphic/geological dynamics in the Alps.  相似文献   

14.
Alpine glacier retreat resulting from global warming since the close of the Little Ice Age in the 19th and 20th centuries has increased the risk and incidence of some geologic and hydrologic hazards in mountainous alpine regions of North America. Abundant loose debris in recently deglaciated areas at the toe of alpine glaciers provides a ready source of sediment during rainstorms or outburst floods. This sediment can cause debris flows and sedimentation problems in downstream areas. Moraines built during the Little Ice Age can trap and store large volumes of water. These natural dams have no controlled outlets and can fail without warning. Many glacier-dammed lakes have grown in size, while ice dams have shrunk, resulting in greater risks of ice-dam failure. The retreat and thinning of glacier ice has left oversteepened, unstable valley walls and has led to increased incidence of rock and debris avalanches.  相似文献   

15.
铜川市地质灾害及其防治对策   总被引:4,自引:0,他引:4  
铜川市是陕西省地质灾害最严重的地区之一。由于大规模地开发煤炭资源及频繁的人类工程经济活动,使该市成为地质灾害的多发区。滑坡、崩塌、地面塌陷、地裂缝等地质灾害分布广,活动频繁,危害程度大。目前,已造成巨额的经济损失和大量人员伤亡,严重地制约着地方经济和社会的可持续发展,危害着人民群众生命财产安全。文中分析了该市地质灾害的主要类型及其分布特征,总结了地质灾害的成因机理。认为该市地质灾害是自然因素和人为因素在一定条件下共同怍用的结果。随着人类活动的日益加剧,人为因素已成为地质灾害发生的主导诱发因素。据统计,全市约有70%的地质灾害是由不规范的工程经济活动所诱发。由此进一步提出了该市地质灾害的防治原则和防治对策,力求有效地预防和减少地质灾害的发生。  相似文献   

16.
江苏地质灾害特征、成因及防治建议   总被引:1,自引:0,他引:1       下载免费PDF全文
谢兴楠 《江苏地质》2009,33(2):154-159
通过对江苏省地质灾害类型、特征、分布和成因的介绍,阐述了对江苏社会经济可持续发展影响最大的地质灾害是当前的地面沉降和未来的海水人侵,并从行政法规管理与技术角度对江苏地质灾害的防治提出了建议。  相似文献   

17.
赵彦宁  孙秀菲 《吉林地质》2012,31(2):117-122
本文根据吉林省地质灾害发育类型及分布特征,分析了其形成条件及易发影响因素,进行了地质灾害易发程度及防治分区,提出了地质灾害防治对策建议。  相似文献   

18.
塔里木盆地是我国最大的半封闭型内陆盆地, 干旱、大风、沙尘暴、洪水以及地震、雪灾等自然灾害频繁.为了提高塔里木盆地城市应对自然灾害的能力, 以阿克苏地区为例, 在广泛借鉴国内外灾害脆弱性评价的指标体系与评价模型的基础上, 以多灾种复合情况为背景, 构建塔里木盆地自然灾害脆弱性评价指标体系, 运用模糊综合评价法进行脆弱性评价, 并对各指标进行对比分析.结果表明: 阿克苏市、新和县、阿瓦提县的高脆弱度值最高, 分别为0.48、0.36及0.40, 属于高脆弱度; 温宿县、沙雅县的中脆弱度值较高, 分别0.24和0.26, 属于中脆弱度; 库车县、拜城县、乌什县、柯坪县的低脆弱度值较高, 分别为0.48、0.45、0.36及0.35, 属于低脆弱度.根据各县市自然灾害脆弱性评价结果, 结合区域特点, 提出了防灾抗灾的对策建议, 对塔里木盆地城市降低脆弱性、减轻自然灾害影响有一定借鉴意义.  相似文献   

19.
青藏交通线的地质环境及地质灾害   总被引:1,自引:0,他引:1  
王治华 《地学前缘》2007,14(6):31-37
以ETM卫星影像为主要遥感信息源,采用数字滑坡技术调查青藏线区域地质环境及大型地质灾害。青藏线区域可分为6个基本地质构造单元,各单元出露不同的第四系堆积及岩石,有不同的构造特征,但构造延伸方向均以EW和NWW走向为主,断裂发育,以隆起抬升为主的新构造运动特别活跃强烈。青藏线区域地形以其不同的起伏特征及不同水系大致可分为北-上行陡坡、中-平缓高原面、南-下行陡坡3段。可能影响青藏交通线的大型地质灾害为与本区高海拔及冻土环境密切相关的冰缘地貌现象,如石冰川、滑坡、泥石流、石海、石流及移动沙丘。  相似文献   

20.
The population of Latin America will be increasing by 130 % between 1970 and the year 2000. Due to excessive rural exodus the urban population grows almost twice as fast as the rural does. The urbanization of the subcontinent must be regarded as being the dominant spatial process in Latin America. It results in fundamental changes of the structure and the way of life of the population as well as in the size and character of the settlements.Three case studies (Popayán/Colombia, Sucre/Bolivia and Santiago/Chile) show that a process of westernization can be observed within the analogous to their size, in the course of which the compact structure of the colonial town pattern is succeeded by a sectorially or cellularly arranged cityorganism.From today's point of view a definite judgement on urbanization as a relevant phenomenon of development cannot yet be made. It can be stated, however, that the southern countries of Latin America which have been urbanized the most show distinct signs of a social and economic take off.  相似文献   

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