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281.
借鉴花岗岩区单元—超单元填图理论方法 ,通过对乌增苏辉长岩体岩石学、岩石化学、微量元素、稀土元素等特征的研究 ,将岩体划分为四个单元  相似文献   
282.
After an earthquake, earthquake emergency response and rescue are important ways to mitigate earthquake-induced losses. Various earthquake emergency maps can provide effective references and guidance to those actions. Currently, related studies include the investigation on symbols of emergency maps, remote sensing emergency mapping and GIS-based mapping methods. However, the existing studies overlook the characteristics of rapidity, dynamicity and variety of presentation methods in making earthquake emergency maps. In this paper, a map template matching method is used to quickly make earthquake emergency maps considering their characteristics. We take investigations on the service objects(users)of the earthquake emergency maps to understand the needs of making earthquake emergency maps. The audience theory in mass media field and map information transmission theory are adopted to classify the users of the earthquake emergency maps into four categories: earthquake emergency commanders, technical staffs for decision-making, earthquake emergency rescuers, and the public. The components of different types of users are described and then their diverse demands in earthquake emergency maps are analyzed, such as the needs of on-field disaster information maps, earthquake information maps, physical geography and social economic maps. Following those needs, we introduce the representation methods of the earthquake emergency maps according to their formats(vector or raster)and contents, such as point symbolization method, kilometer grid method, line symbolization method and range method. Then, we study the rapid plotting method of earthquake emergency map based on map template matching method. The core steps of the method include: 1)before earthquake, the templates of different earthquake emergency maps are designed, prepared and connect the earthquake emergency features with their related spatial database. The map layout and map elements are stored in the templates. 2)After earthquake, the earthquake emergency features will be generated from seismic models(such as attenuation model of earthquake magnitude and seismic intensity)or the information obtained from field investigation. 3)Corresponding earthquake emergency map template is selected in accordance with the generated seismic features. And the features are used to update related features inside the selected template. 4)Minor adjustments are made such as to the map scale and some map annotations to finally generate the formal earthquake emergency map. Architecture of template system of the earthquake emergency maps is designed, including map user level, map template level, template layer level and map element level. Regrading to the architecture, the general map template of earthquake emergency is presented which includes four main regions: title region, main picture region, auxiliary region and annotation region. The main picture region is the essential, which lays geographic background maps and earthquake emergency features. Finally, an earthquake emergency mapping system is developed. Based on the system, a case study is presented, which demonstrates making a simulated seismic intensity influence map. From three aspects, the case presents the application of the template-matching method including: generating earthquake emergency features, substituting the features inside the template with the generated features, and revising map annotations. Therefore, the map template matching method is verified so that it can be used to quickly generate various earthquake emergency maps.  相似文献   
283.
 Systematic stream sediment investigation in a periurban area surrounding Genoa (Italy) revealed the existence of a significant mercury anomaly localized on the main (3rd rank) bed of the Bisagno river. Statistical multivariate analysis of elemental abundances points out the anthropic nature of this contamination. Because of the well-known bioaccumulation of Hg in contaminated media, attention must be focused on the risks associated with the discovered pollution. Received: 30 November 1999 · Accepted: 22 March 2000  相似文献   
284.
GROUNDWATER QUALITY AND CONTAMINATION INDEX MAPPING IN CHANGCHUN CITY, CHINA   总被引:13,自引:0,他引:13  
1INTRODUCTIONGroundwater in Changchun City assures about 45% of total water supply. Drinking water supply of Chang-chun City was mostly served by surface water from Shitoukoumen and Xinlicheng reservoirs located in the east and south of the city (ZHANG, 1993). However, with the development of urban construction the ground-water especially from deep boreholes is also used for drinking purpose in suburban areas. The urbanization process in Changchun City threatens the groundwater quali…  相似文献   
285.
Digital geological mapping fundamentally broke through the traditional working pattern,successfully carried out the geological mapping digitalization.By using the RGMAP system to field digital geological mapping,the authors summarized the method of work and the work flow of the RGMAPGIS during the field geological survey.First,we prepared material,set up the PRB gallery,then put the geographic base map under the background maplayer and organizing the field hand map,forming the field factual datum map.At last,the geological space database is formed.  相似文献   
286.
省级基础测绘1∶1万比例尺数字测绘产品包括DEM,DOM,DLG,DRG、元数据、文档簿等。为验证数字测绘产品最终成果的精度和可靠性,可选择多种方案进行质量检验;在选择检验方案时,既要考虑检验的成本、周期,又要考虑检验方案的科学性和严密性。针对不同的数字测绘产品,该文给出了与之相适应的检验方法,并阐明了检验内容和注意事项。  相似文献   
287.
Specifying the location of a rural residence is a common geographic problem. Most addressing systems are designed for urban areas and are not applicable to rural areas. The mile marker addressing system meets all of the requirements for a rural addressing system. With the addition of computer mapping techniques, rural addressing can be done efficiently and can provide the basis for a county's computer mapping system. Projects in New Mexico provide several examples of computerized rural addressing projects.  相似文献   
288.
The dissolved methane (CH4) plume rising from the crater of the blowout well 22/4b in the Central North Sea was mapped during stratified water column conditions. Geochemical surveys were conducted close to the seafloor at 80.3 m water depth, below the thermocline (61.1 m), and in the mixed surface layer (13.2 m) using membrane inlet mass spectrometry (MIMS) in combination with a towed CTD. Seawater was continuously transferred from the respective depth levels of the CTD to the MIMS by using an inline submersible pump. Close to the seafloor a well-defined CH4 plume extended from the bubble release site ∼460 m towards the southwest. Along this distance CH4 concentrations decreased from a maximum of 7872 nmol l−1 to less than 250 nmol l−1. Below the thermocline the well-defined CH4 plume shape encountered at the seafloor was distorted and filaments were observed that extended towards the west and southwest in relation to current direction. Where the core of the bubble plume intersected this depth layer, footprints of high CH4 concentrations of up to 17,900 nmol l−1 were observed. In the mixed surface layer the CH4 distribution with a maximum of up to 3654 nmol l−1 was confined to a small patch of ∼60 m in diameter. The determination of the water column CH4 inventories revealed that CH4 transfer across the thermocline was strongly impeded as only ∼3% of the total water column inventory was located in the mixed surface layer. Best estimate of the CH4 seabed release from the blowout was 1751 tons yr−1. The fate of the trapped CH4 (∼97%) that does not immediately reach the atmosphere remains speculative. In wintertime, when the water column becomes well mixed as well as during storm events newly released CH4 and the trapped CH4 pool can be transported rapidly to the sea surface and emitted into the atmosphere.  相似文献   
289.
莱芜地处山东省中部,区位优势明显,产业基础良好。经济发展战略的实施,迫切需要基础地理信息数据提供包括地理环境、生态体系以及战略布局等全方位的科学分析和辅助决策。该文分析了莱芜市基础测绘发展现状,找出了基础测绘工作中的差距,认为今后应建立完善稳定的基础测绘经费投入机制,加快成果的开发与应用。  相似文献   
290.
以济南市房屋安全管理云的整体设计与实现为研究内容,充分论述了该项目的建设目标、架构设计、建设内容和创新点,建设过程中广泛的引入了大数据、云计算、三维实景测量等先进技术手段,运用SuperMap系列GIS软件进行开发设计,为房屋安全管理模式的创新提供了有效的技术保障,为智慧房管建设提供了有益的探索和实践。  相似文献   
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