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331.
恰什坎萨伊沟玄武岩年代学、地球化学特征及其对北阿尔金洋盆闭合过程的制约 总被引:5,自引:0,他引:5
北阿尔金恰什坎萨伊沟红柳泉以南早古生代蛇绿岩剖面发育两段玄武岩岩片.北段玄武岩锆石LA-ICP-MS U-Pb定年与前人对南段玄武岩定年结果(晚奥陶世)相近,表明该玄武岩形成于中—晚奥陶世;样品TR050-10-1锆石热干扰年龄为421~412 Ma、395~388 Ma和283~228Ma,TR050-13-1锆石热干扰年龄为442~434Ma、415Ma和241~221Ma.地球化学特征显示北段玄武岩和南段玄武岩的岩浆演化过程中均以单斜辉石结晶分异为主,仅表现极轻微地壳物质混染;二者均来自尖晶石二辉橄榄岩地幔源区,前者源区为原始尖晶石二辉橄榄岩相,后者源区为原始—亏损尖晶石二辉橄榄岩过渡相,前者的部分熔融程度更高.微量元素、稀土元素及构造判别图解指示其为形成于聚合背景下的E-MORB型拉斑玄武岩,具弧后盆地性质.结合区域资料,提出北阿尔金早古生代洋盆4阶段闭合模式:①早期俯冲阶段(∈2~O1),②晚期俯冲阶段(O1~O3),③俯冲-碰撞转换阶段(O3~S2),④后碰撞造山阶段(S3~D2). 相似文献
332.
多孔介质广泛存在于地下岩土结构、工程材料、生物体中,由于多孔介质微结构的复杂性,多孔介质渗流问题受到广泛关注。总结介绍了多孔介质渗流理论在国内外的研究现状,对多孔介质的描述、渗流问题的研究方法以及多孔介质中溶质运移、热量运移以及数值模型等方面的研究进展作了评述,并就多孔介质渗流理论在环境、农业、生态等领域的应用与发展方向提出看法。 相似文献
333.
《China Geology》2018,1(2):286-303
Nanogeology is a subject that is a combination of geology and nanoscale science, and it has been a frontier field in recent years. It is also a new subject with the features of intersectionality and multidisciplinary. Digging deeper into geological problems and nanoscale phenomena helps better revealing the more essential mechanisms and processes in geological science, which is also an evitable path in the development of geology. In this paper, we elaborate the concept, feature and main subdisciplines, and summarize three stages of nanogeology development from preliminary research in the 1990s to subject formation in China. After summarizing the researchers’ achievements in this field, we illustrate some primary research progresses of nanogeology in China as eight subdisciplines. On the basis of the above content, we propose the development prospect of nanogeology in China. There are many geologic problems with scientific values and economic benefits, such as research of geologic fundamental problems, resource exploration and development, mechanism study and prediction of geological activities (disasters), mechanism research and management of environmental pollution and others. Nanogeology has a great potential in China to solve all of these problems. As a result, the theories and methods of nanogeology will become enriching and advanced. It offers important theoretical basis and technological methods to deal with major issues concerning the national economy and the people’s livelihoods, such as the prediction of geological activities, as well as resource distribution and its exploration and utilization. 相似文献
334.
Stefan Bouzarovski 《Area》2009,41(4):452-463
Energy developments in the post-Communist states of Eastern and Central Europe (ECE) have a major impact on global energy security and sustainability, thanks to this region's key geographical position between the energy-exporting states of the former Soviet Union, on the one hand, and the energy-importing states of Western and Southern Europe, on the other. At the same time, post-socialist reforms of energy industries in this region provide unique insights into the complex relations of power, economic transformation and spatial inequality that govern energy production and consumption. This paper therefore aims to provide an initial look at some of the theoretical and policy issues that underpin the emergent 'geographies' of energy reform in ECE, as well as their embeddedness in relations of power stemming from organisational, infrastructural and economic inequalities in the region. It employs an analysis of local news reports, policy papers and statistical data to examine the intricate institutional networks and spatial formations that have governed the energy transformation process. In broader terms, the paper aims to emphasise the important role that human geography can play in making sense of the territorial differences and frictions that have emerged during the post-socialist reform process, while challenging the idea of a 'neat' neoliberal transition from a centrally planned to a market-based mode of energy regulation . 相似文献
335.
地理格网模型研究进展 总被引:14,自引:2,他引:12
地理格网系统起源于早期的制图研究,并发展成为表达复杂地理现象、综合分析自然与人文数据、模拟地理系统功能与行为的基本方法。地理格网系统的组成包括格元、格边和格点,格元代表了区域面状特征,格点确定了格元的基本位置和点状特征,格边用于度量格元间的通量关系。在现代地球测量技术驱动下,地理格网系统的功能从传统的地图定位框架与地理现象表达,进一步拓展出多源地理空间数据融合、地理综合分析等新功能。研究椭球空间下的地理格网系统构建模型、误差分布、地学计算等是地理格网系统研究的前沿和基础性科学问题。 相似文献
336.
文化创意产业的地理学研究进展 总被引:6,自引:0,他引:6
从20世纪90年代开始,西方人文地理学与社会学、新闻传播学、城市规划、经济学等学科一道对文化创意产业进行了一系列的研究。这些研究涉及了很多议题。其中与地理学关系较为密切的包括:文化创意产业的概念和特征;产业的空间集聚;城市环境与文化创意产业发展的关系;以及文化创意产业研究的方法等。由于文化创意产业作为一种经济现象是新生事物,上述每一个议题都充满争议。西方地理学在这一领域取得了引人瞩目的成就,并且对城市政策、文化政策领域产生了实质性的影响,十分值得我国地理学界加以借鉴。针对我国国情,笔者指出文化创意产业集聚区的发展政策,地方社会文化环境对文化创意产业发展的影响,文化、经济与地理理论的结合应当是我国地理学界当前主要关注的议题。 相似文献
337.
This paper reviews the history and progress of research on active tectonics in China and overseas. By giving a brief introduction on the history of active tectonic research in China and other countries, the paper sums up the process and development of quantitative investigation of active tectonics since the 1980s. The focus is on the main efforts and progress made in China on certain aspects of research, such as basic surveys and applied investigation of active tectonics, the study of theories related to regional active tectonics and their kinematics and geodynamics, surveys on coupling relations between deep and shallow structures, active fault surveys and prospecting and seismic hazard assessment in urban areas, as well as the efforts made using Quaternary geochronology. Furthermore, the paper looks back on Chinese quantitative investigation of active tectonics in China and sums up cognitions derived from studies on the determination of several basic and measurable parameters of active tectonics. These parameters include the length of fault and fault segmentation, coseismic slip and cumulative slip, fault slip rate, the sequence of paleoearthquake events and the time elapsed since the most recent event. At the same time, efforts and progress made in China on assessing the long-term seismic potential for active faults and evaluating the risk from potential active fault movement have been reviewed by summarizing research on developing theories, models, methods and the application of time-dependent seismic potential to prohabilistic assessment, magnitude estimation for potential earthquakes on active faults, and the forecast of potential risk caused by active fault movement. Finally, in consideration of the realities and problems in the research of active tectonics in China, the authors put forward several suggestions for issues worthy of more attention for further investigation in the future. 相似文献
338.
张海滨 《气候变化研究进展》2009,5(3):145-150
近年来,美国关于气候变化对国家安全影响的研究成果频出。在概述其研究现状及主要成果的基础上,分析了美国在该领域研究的特点及其对我国开展相关研究的启示。美国关于气候变化影响国家安全的研究成果主要体现在围绕气候变化影响美国国家安全的方式、范围、程度以及美国的应对之策等几个方面展开了全面而深入的讨论。其突出特色是:第一,在研究理论和方法方面,与时俱进,转型较快;第二,在研究内容方面,既视野开阔,又有较强的针对性;第三,在研究水平上呈现逐步提高的趋势;第四,在研究体制上,形成官、学、研三位一体的联合研究体制。当前,我国的相关研究还处在起步阶段,在未来的研究中可以借鉴美国的一些有益经验。 相似文献
339.
青海高原沙漠化研究进展 总被引:7,自引:1,他引:6
20世纪50年代末到21世纪初,对青海高原沙漠化的分布、基本特征、沙丘类型、形成演化、风沙移动规律、野外观测、沙化监测的科学考察研究到防沙治沙试验的过程;从地域上涉及了青海的柴达木盆地、共和盆地、青海湖盆地、黄河源区和长江源区全部5个沙漠化土地分布地区,全面综述了高原沙漠化研究的成果、防沙治沙经验和研究进展,提出了存在的问题及今后研究的内容。 相似文献
340.