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21.
北京房山世界地质公园岩溶景观特色   总被引:2,自引:2,他引:0  
吕金波 《城市地质》2007,2(3):26-30
北京房山世界地质公园是以岩溶洞穴景观和峰丛地貌景观为主题的地质公园。大石河流域发育中奥陶统马家沟组石灰岩,自上而下,依次发育鸡毛洞、银狐洞、石花洞和孔水洞,由一条地下暗河将其连为一个洞系,其水源补给点在大石河上游,排泄点为孔水洞。周口店猿人遗址属于中奥陶统马家沟组岩溶洞穴。拒马河流域发育中元古界雾速山组白云岩,岩溶洞穴包括云水洞、仙栖洞、龙仙宫和三清洞,均属唐县期夷平面时期的产物。拒马河流域地层平缓的中元古界雾速山组峰丛地貌区东从张坊起,西至大沙地,南临笔架山,北抵石人峰,流域面积395km~2,其中碳酸盐岩岩石面积占360km~2,山体上部的岩石被溶解,形成峰丛地貌景观。  相似文献   
22.
苏扣林  丁兴  郭宇  石晓龙 《中国地质》2021,48(1):161-172
广州市增城地质公园发育有大量的燕山期安山岩和流纹岩,由于缺少详细的岩石地球化学研究,这些火山岩的成因和所代表的大地构造意义一直未明确.文章对上述火山岩进行了较为系统的全岩地球化学以及同位素地球化学分析.研究结果显示,安山岩具有安第斯型火山岩特点,显示Nb、Ta、Sr和Ti的亏损,Isr值介于0.70332~0.7144...  相似文献   
23.
地磁匹配特征量的选择   总被引:1,自引:0,他引:1  
论文旨在选择合适的地磁特征量用于匹配制导.从地磁匹配的实际要求出发,提出了选择匹配特征量时应重点考虑的几个因素,通过理论分析初步拟定了选取准则,并针对特定区域,依据IGRF(International Geomagnetic Reference Field)和WMM(World Magnetic Model)计算出的地磁数据,结合选取准则进行了综合分析,给出了初选结果,对地磁匹配基准图的制备、实时图的获取、匹配算法的研究,以及地磁场资源应用于其他领域的相关研究有一定的借鉴意义.  相似文献   
24.
Spatial Accessibility to Health Care Facilities in Suhum District,Ghana   总被引:1,自引:1,他引:1  
To improve geographical accessibility to health facilities in rural Ghana, it has been recommended that additional health facilities be built. Resource constraints make this recommendation infeasible. Using location-allocation models, this paper demonstrates that in the Suhum District of Ghana substantial improvements in accessibility can be achieved with better locational choices and without additional facilities. Also, additional facilities will produce little improvement in accessibility if location is not explicitly considered. The paper demonstrates the utility of location-allocation models for improving accessibility to services in the Third World.  相似文献   
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26.
Pasargadae complex had been the main center of Persian history during the Achaemenian period (560–330 bc), registered as one of the world heritage sites by UNESCO in 2004. This research is an attempt to recognize the natural setting and landscape of Pasargadae during the Achaemenian period, in Iran. The method is based on the application of a multi-layer technique. Collected data by fieldwork, especially in geology, hydrology, and hydrogeology, along with the analysis of aerial data and satellite information provided the baseline information for preparing historic and environmental layers and have made it possible to recognize a natural lakelet in the this area. The results show that the geometry of lakelet together with the ancient river of Pasargadae had been the main elements that formed the character of the site; they were also important in the locations of buildings in the Pasargadae complex.  相似文献   
27.
Michael C. Ewers 《GeoJournal》2007,68(2-3):119-130
Urban areas compete with one another for people, goods, capital, ideas and other inputs of economic activity. Under the rubric of globalization, instead of only maintaining or improving the initial stock of assets in a city, the power of a place to attract outside flows of economic activity from elsewhere is increasingly important to economic development. Similarly, global or world cities are characterized as the command and control points through which these global economic flows operate. In response to the heightened mobility of highly-skilled labor across national borders, research has begun to examine the role of international human capital as an economic flow. This paper will examine the role of places in determining where the highly-skilled go in the global economy by viewing global city command and control functions as requiring unique labor flows. By reviewing the evidence found in the literature, we can better understand the potential for urban areas to compete for highly-skilled labor in the global economy. Known indicators of place attractiveness are assessed to examine the relationship between the economic trajectories of cities and their labor requirements. Cities are situated between firms and states as the key place-based actors which influence the mobility of highly-skilled labor. Finally, the paper also examines measurement issues and methodological problems in creating indices of world cities as well as explores possibilities for new research.  相似文献   
28.
世界应力图2000版( WSM2000)介绍及使用说明   总被引:5,自引:0,他引:5  
全球地壳应力状态对于地学及相关领域科学研究意义重大,因此测量全球地壳应力并绘制全球地壳应力图一直受到国际地学界广泛关注.1986年开始实施的世界应力图计划(WSMP:World Stress Map Project,以下简称WSM)经各国专家多年合作和努力工作,现已出版了最新WSM2000版本应力数据库.该数据库在WSMl997版基础上新增收录了4216个观测数据,使其总共包含了全球10920个可靠应力测量数据,并绘制了全球应力图和部分地区的局部应力图,为地质地球物理研究提供了准确详细的应力数据.本文结合WSM官方网站的资料从数据库结构、数据来源、数据质量、数据摘要描述等方面介绍WSM2000数据库,以使国内研究迅速利用此宝贵的数据资源.  相似文献   
29.
Remote sensing technology has been widely recognized for contributing to emergency response efforts after the World Trade Center attack on September 11th, 2001. The need to coordinate activities in the midst of a dense, yet relatively small area, made the combination of imagery and mapped data strategically useful. This paper reviews the role played by aerial photography, satellite imagery, and LIDAR data at Ground Zero. It examines how emergency managers utilized these datasets, and identifies significant problems that were encountered. It goes on to explore additional ways in which imagery could have been used, while presenting recommendations for more effective use in future disasters and Homeland Security applications. To plan adequately for future events, it was important to capture knowledge from individuals who responded to the World Trade Center attack. In recognition, interviews with key emergency management and geographic information system (GIS) personnel provide the basis of this paper. Successful techniques should not be forgotten, or serious problems dismissed. Although widely used after September 11th, it is important to recognize that with better planning, remote sensing and GIS could have played an even greater role. Together with a data acquisition timeline, an expanded discussion of these issues is available in the MCEER/NSF report “Emergency Response in the Wake of the World Trade Center Attack; The Remote Sensing Perspective” (Huyck and Adams, 2002)  相似文献   
30.
周兰云  尚艳丽  马传顺 《地下水》2006,28(2):53-54,57
为合理开发利用地下水资源提供科学依据,确保地下水资源可持续利用,防止由于超采地下水而诱发环境危害,对泰安市世行贷款二期项目区地下水动态变化规律、水资源的分布特征进行了分析研究,提出了地下水合理开发利用的建议.  相似文献   
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