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1.
卢昌仁 《冰川冻土》2003,25(8):127-132
根据拉萨市呈带状布局的现状,结合拉萨市城市规划和铁路线路引入方向及路网规划等具体情况,提出拉萨地区铁路按客货分设的思路进行方案比选,对拉萨铁路地区总图规划研究,提出了总图规划方案,主要站段位置的构想,肝对近期工程的实施方案作了简要的论述。  相似文献   

2.
杜蓓 《冰川冻土》2003,25(Z1):190-194
青藏铁路所经地区生态环境十分脆弱并呈退化趋势, 在此地区建设铁路, 由于工程建设大面积地扰动地表和植被, 大量的土石方开挖, 必将产生一系列的环境问题. 通过对青藏线唐古拉至拉萨段铁路沿线水土流失现状及水土保持现状的综合分析, 结合铁路工程特点和环境特征, 提出了青藏铁路唐古拉至拉萨段水土流失防治对策及建议, 达到遏制铁路沿线水土流失的进一步发展, 改善当地生态环境, 维护铁路工程正常运营的目的.  相似文献   

3.
以湛江铁路枢纽现状和路网构成为基础,就枢纽内近、远期引入的茂湛线、合湛线、东海岛线、湛海二线及海峡客专,按照"点线协调、客货分线、减少交叉、整合货运"的总体思路,以新建湛江西(客)站为重点,提出湛江枢纽总图规划方案。  相似文献   

4.
拉萨市夏季大气降尘单颗粒矿物组成及其形貌特征   总被引:3,自引:0,他引:3       下载免费PDF全文
应用带能谱的电子扫描电镜(SEM-EDX)对拉萨市夏季正常天气下收集的大气自然沉降气溶胶样品进行分析,研究了拉萨市大气降尘矿物组成和各种物相形貌特征信息。拉萨市大气颗粒物含有硅酸盐颗粒、富钙颗粒、富铁颗粒、富碳颗粒(燃煤飞灰颗粒和燃油飞灰颗粒)和植物残体颗粒。根据颗粒物数量统计发现拉萨市大气颗粒物以硅酸盐颗粒为主,富钙颗粒和富铁颗粒次之,需要指出的是以燃油飞灰为主的富碳颗粒已占到一定比重,说明以燃油为主的机动车尾气对拉萨大气污染在加强。研究结果表明,大气降尘矿物成分及其形貌特征可以用作判定污染物来源的重要标志,拉萨大气中颗粒来源的多样性决定了治理措施也应综合进行。  相似文献   

5.
扎西林卡后山崩塌为西藏拉萨地区及周边具有代表性的崩塌类型,通过实地地质调查、工程测量、地质测绘等工作手段,初步查明了地质环境条件,查明了危岩体分布及形态特征,在此基础上使用赤平投影法作出稳定性评价,并基于ROCKFALL进行了失稳危险性评价;确定了成因机制、稳定性、崩塌落石运动轨迹、运动距离等,有针对性的提出防治措施,对拉萨市周边及类似灾害的评价、治理具有一定的借鉴意义。  相似文献   

6.
杜蓓 《冰川冻土》2003,25(8):190-194
青藏铁路所经地区生态环境十分脆弱并呈退化趋势,在此地区建设铁路。由于工程建设大面积地扰动地表和植被,大量的土石方开挖,必将产生一系列的环境问题。通过对青藏线唐古拉至拉萨段铁路沿线水土流失现状及水土保持现状的综合分析,结合铁路工程特点和环境特征,提出了青藏铁路唐古拉至拉萨段水土流失防治对策及建议,达到遏制铁路沿线水土流失的进一步发展,改善当地生态环境,维护铁路工程正常运营的目的。  相似文献   

7.
土地资源与总图在社会经济活动中越来越凸显其重要地位,马钢传统的土地总图管理模式已不适应现代土地总图管理发展要求.本文提出了马钢土地总图管理信息化解决方案并将其应用于具体的土地总图管理中.实践证明,该成果的应用有效利用了信息资源,满足决策部门和业务部门的数据需求,实现资源共享和信息发布,提高了土地总图管理的工作效率与管理水平.  相似文献   

8.
应用大系统递阶分析的原理和方法,针对京津唐地区水资源大系统供水规划和调度问题,建立了京津唐地区水资源大系统供水规划和调度优化三级递阶模型和三层递阶模拟模型.提出模拟技术和优化方法相结合的求解方法,并应用该模型对2000、2020水平年近40个组合方案进行运算,对其中较好的20个方案运用所建立的京津唐水资源规划决策支持系统进行多目标综合评价和按优排序,并提出了具体建议.  相似文献   

9.
刘忠旗 《冰川冻土》2003,25(Z1):119-122
在青藏高原修建铁路其困难程度是空前的, 工程的施工组织所面临的问题也是多样的. 就青藏线格尔木至拉萨段施组方案研究和设计过程中对于劳动保护、环境保护、工期确定等几个要点问题的思考和解决做了简要阐述, 体现了这一国家重点工程施工组织的主要指导思想.  相似文献   

10.
川藏铁路是我国正在规划建设的重要铁路干线之一,是西部大通道的重要组成部分。该铁路线横跨扬子板块、川滇地块、羌塘地块和拉萨地块等大地构造单元,在复杂的地质构造背景条件下,川藏铁路沿线活动断裂、地震和地质灾害极为发育,严重制约着川藏铁路的规划建设。在野外地质调查、钻探、地应力测量和室内测试分析的基础上,对川藏铁路规划建设中可能遇到的活动断裂、高地应力、高地温、岩爆和地质灾害等主要环境工程地质问题进行了论述分析,认为:川藏铁路沿线及邻区发育有54条区域活动断裂,其中对铁路有直接重要影响的全新世活动断裂有17条;研究区内地震活动频繁,约有50%的规划线路位于地震动峰值加速度>02 g地区,部分地段>04 g,潜在地震风险大;铁路沿线主要的地质灾害类型为崩塌、滑坡和泥石流,地质灾害受活动断裂影响强烈,部分地段发育有高速远程滑坡;川藏铁路沿线构造应力场和地热场复杂,深埋隧道工程建设时容易发生岩爆、软岩大变形和高温热害等工程地质问题。  相似文献   

11.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

12.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

13.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

14.
Important tendencies in development of the world mineral-resources sector at the beginning of the 21st century were an increase in production and consumption of mineral materials differentiated by types of metals and nonmetallic mineral raw materials, by countries and regions, as well as the concentration of the production of mineral raw materials in a small number of countries, and a reduction in industrial reserves of minerals in the world economy, even at the current stage of their extraction. These tendencies should be taken into account in working out a strategy for development of the Russian mineral raw-material base.  相似文献   

15.
Taking the example of W Sudan, an analysis of the climatic incidents leading to the two recent famine disasters is made. On this natural background, the human side is investigated. Focus is directed towards the fragile economic structure of the famine-prone population groups. An early-warning system for famine in the Sahelian Zone is proposed taking grain production and storage, livestock development and the relationship between the prices of livestock and grain as major indicators.  相似文献   

16.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

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19.
郯庐断裂南段研究进展与断裂性质讨论   总被引:13,自引:3,他引:13  
据1:5万区域地质调查和专题研究资料,就郯庐断裂带是否南延与消失的原因,其与大别—苏鲁造山带交截形成的假位错效应,以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上,讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。  相似文献   

20.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

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