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1.
Numerical modelling was done at the Cold Lake Air Weapons Range, Canada, to test whether the dissolved RDX and nitrate detected in groundwater come from the same sources, and to predict whether contamination poses a threat to the surface water receptors near the site. Military live fire training activities may indeed pose a risk of contamination to groundwater resources, however field investigations on military bases are quite recent, and little information is available on the long-term behaviour of munition residues related contaminants. Very limited information was available about the contaminant source zones, which were assigned based on our knowledge of current training activities. The RDX plume was well represented with the model, but the heterogeneous distribution of nitrate concentrations was more difficult to reproduce. It was nonetheless determined that both contaminants originate from the same areas. According to the model, both contaminants should reach the nearby river, but concentrations in the river should remain very low if the source zone concentration does not change. Finally, the model allowed the recommendation of a new location for the main bombing target, which would offer added protection to the river and the lake into which it flows.  相似文献   
2.
INTRODUCTIoNTheDabie-Suluregion,Chinahasbeenrecognizedasthelargestultrahigh-pressuremetamorphic(UHPM)(peakp>2.7GPa)andHPMbeltsintheworld,andattractedexten-siveinterestfrominternationalgeoscientists.AwealthofpublicationsexistsabouttheoccurrenceofUHPMindexmin-erals,thegeochronology,metamorphicPTpaths,andthelarge-scaleconceptualtectonicevolutionofUHPMandhigh-pressuremetamorphic(HPM)rocksintheDabie-Suluregion.Morerecentoverviewsaregiven'byErnstetal.(1995),Liouetal.(l996),andHackere…  相似文献   
3.
INTRODUCTIONTheageofultrahigh-pressuremetamorphism(UHPM)andhigh-pressuremetamorphism(HPM)hasbeendeterminedat24OMato2loMabyseveralchronologicalmethods(Lietal.,1998;Maruyamaetal.,l998iAmesetal.,l9961Hack-erandWang,l995;Johnetal,,1994).Theseagedatare-f1ecttheTriassicobliquecollisionbetweentheSino-KoreanandYangtzecratons.ThermobarometricestimatesoftheUH-PMandHPMintheDabie-SuluregionshowthatthecoldcontinentalcrustmaterialoftheYangtzecratonwasunder-thrust,alongthesuture,northwardtoma…  相似文献   
4.
The increasing focus on new biological risks and threats together with unsatisfactory progress in international negotiations about biological disarmament have opened up new questions about the further development of the biological weapons regime. The present paper focuses on the politics of biological (post-)disarmament from the perspective of critical security studies and scrutinizes the changing role of scientific experts in relation to the shifting understanding of the threat of bioweapons. Specifically, it argues that the move toward a networked approach to biosecurity governance relying on an increasing role of experts and nonstate actors may be read in the context of a broader insecuritization of biological risks and threats and the evolution of new techniques of government. Drawing on sociological approaches in security studies, the paper unfolds the connections between the construction of biosecurity and the politics of expertise and explores the changing role of scientific experts in biological disarmament. The paper also finds that the attempts to manage bio-insecurity create demand for new types of expertise and empower actors with a specific form of knowledge who can navigate in the changed structural environment, and enable new forms of governing security.  相似文献   
5.
BOOK REVIEWS     
Book Reviewed in this article: Unfairly Structured Cities . Blair Badcock Religion and Rural Revolt . Janos M. Bak and Gerhard Benecke The Industrial Geography of Canada . Anthony Blackbourn and Robert G. Putnam The Cuban-American Experience, Culture, Images, and Perspectives. Thomas D. Boswell and James R. Curtis Quaternary Paleoclimatology . R. S. Bradley Development and Crisis in Brazil, 1930–1983 . Luiz Bresser Pereiras Centres of Origin in Biogeography . John C. Briggs Analytical Urban Geography . Martin Cadwallader Geomorphology . Richard J. Chorley , Stanley A. Schumm, and David E. Sugden South Africa: The Impact of Past Geographies . A. J. Christopher The Geography of Underdevelopment. A Critical Survey . D. K. Forbes Health Care in Developing Countries . Wilbert M. Gesler Place to Grow Old: The Meaning of Environment in Old Age . Stephen M. Golant The Emerging Marine Economy of the Pacific . Chennat Gopalakrishnan An Introduction to Agricultural Geography . David B. Grigg The Soviet Union: A Geographical Study . G. Melvyn Howe Geographical Aspects of Health: Essays in Honour of Andrew Learmonth . N. D. Mc Glashan and J. R. Blunden Physical Geography: A Landscape Appreciation . Tom L. Mc Knight Mountain Experience. The Psychology and Sociology of Adventure. Richard G. Mitchell Jr . Systematic and Regional Biogeography. Stanley A. Morain The Economic Transformation of American Cities. T. J. Noyelle and T. M. Stanback , Jr . Normal Accidents: Living With High-Risk Technologies. Charles Perrow Vanishing Farmland: A Legal Solution for the States. Sarah E. Redfield Applied Methods of Regional Analysis: The Spatial Dimensions of Development Policy. Dennis A. Rondinelli Urbanization in Romania. A Geography of Social and Economic Change Since Independence. Per Ronnas Statistical Techniques in Geographical Analysis. Gareth Shaw and Dennis Wheeler The Granite Garden: Urban Nature and Human Design. Anne Whiston Spirn Political Geography: Recent Advances and Future Directions. Peter Taylor and John House Geographia y Medio Ambiente. Manuel Valenzuela -Rubío Nãgara and Commandery: Origins of the Southeast Asian Urban Traditions. Paul Wheatley The Common Fisheries Policy of the European Community. Mark Wise Geography and Gender. Women and Geography Study Group of the IBG Technological Hazards. D. J. Zeigler , J. H. Johnson , S. D. Brunn  相似文献   
6.
BOOK REVIEWS     
Book Reviewed in this article: Main Street: Northeastern Oregon: The Founding and Development of Small Towns . Barbara Ruth Bailey . Food Politics: The Regional Conflict . David N. Balaam and Michael J. Carey , eds. The International Economy and Industrial Development: Trade and Investment in the Third World . R. Ballance , J. Ansari and H. Singer . Neighborhoods in Urban America . Ronald H. Bayor , ed. The English Heartland . By Robert Beckinsale and Monica Beckinsale . Regional Dimensions of Industrial Policy . Michael E. Bell and Paul S. Lande , eds. Tension Areas of the World . D. Gordon Bennett , ed. Latin America: an Introductory Survey . B. W. Blouet and O. M. Blouet , eds. Integration and Division: Geographical Perspectives on the Northern Ireland Problem . Frederick W. Boal and J. Neville H. Douglas , eds. Energy and Land Use . Robert W. Burchell and David Listokin , eds. Slopes and Weathering . Michael Clarke and John Small . Alaska's Rural Development . Peter G. Cornwall and Gerald Mc Beath , eds. The Politics of Park Design: A History of Urban Parks in America . Galen Cranz . World Congress on Land Policy, 1980, Proceedings . Matthew Cullen and Sharon Woolery , eds. Oregon Divided: A Regional Geography . Samuel N. Dicken and Emily F. Dicken . Urban Food Marketing and Third World Rural Development . T. Scarlett Epstein . South Africa: Spatial Frameworks for Development . T. J. D. Fair . Institutions and Geographical Patterns . Robin Flowerdew , ed. Industrialization of U.S. Agriculture, An Interpretive Atlas . Howard F. Gregor . Planning Theory: Prospects for the 1980s . Patsy Healy , Glen Mc Dougall and Michael J. Thomas , eds. Neighborhood Mobilization: Redevelopment and Response . Jeffrey R. Henig . The American Urban System: A Geographical Perspective . R. J. Johnston . Climate, History and the Modern World . Hubert H. Lamb . Climate and History: Studies in Past Climates and Their Impact on Man . T. M. L. Wigley , M. J. Ingram and G. Farmer . China: Railways and Agricultural Development, 1875–1935 . Ernest P. Liang . A Desirable Energy Future—A National Perspective . Robert S. Livingston , T. D. Anderson , T. M. Besmann , M. Olszewski , A. M. Perry , and C. D. West . Topothesia: Essays Presented to T. S. Ó Máille . B. S. Mac Aodha , ed. Transportation for the Poor: Research in Rural Mobility . Hal S. Maggied . Land Uses in American Cities . Harold M. Mayer and Charles R. Haves . Industrial Organisation and Location . Philip Mc Dermott and Michael Taylor . Human Adaptability: an Introduction to Ecological Anthropology . Emilio F. Moran . Regional Analysis and the New International Division of Labor . Frank Moulaert and Patricia W. Salinas , eds. The Nuclear War Atlas. Victoriaville, Quebec, Canada : Urbanization and Environmental Quality . Isao Orishimo . The Garden of Eden: The Botanic Garden and the Re-Creation of Paradise . John Prest . Earthfire, The Eruption of Mount St. Helens . Charles Rosenfeld and Robert Cooke . Contest for the South China Sea . Marwyn S. Samuels . The Future of the Wetlands: Assessing Visual-Cultural Values . Richard C. Smardon , ed. Tucson: the Life and Times of An American City. C. L. Sonnichsen . The Geography of Multinationals . Michael Taylor and Nigel Thrift , eds. Impact of Marine Pollution on Society . Virginia Tippie and Dana Kester . Reviving the Industrial City: the Politics of Urban Renewal in Lyon and Birmingham . Jerry A. Webman . Andean Reflections: Letters from Carl O. Sauer While on a South American Trip under a Grant from the Rockefeller Foundation, 1942 . Robert C. West , ed. Cartographic Drawing with Computers . P. Yoeli .  相似文献   
7.
Book Reviewed in this article:

Main Street: Northeastern Oregon: The Founding and Development of Small Towns. Barbara Ruth Bailey.

Food Politics: The Regional Conflict. David N. Balaam and Michael J. Carey, eds.

The International Economy and Industrial Development: Trade and Investment in the Third World. R. Ballance, J. Ansari and H. Singer.

Neighborhoods in Urban America. Ronald H. Bayor, ed.

The English Heartland. By Robert Beckinsale and Monica Beckinsale.

Regional Dimensions of Industrial Policy. Michael E. Bell and Paul S. Lande, eds.

Tension Areas of the World. D. Gordon Bennett, ed.

Latin America: an Introductory Survey. B. W. Blouet and O. M. Blouet, eds.

Integration and Division: Geographical Perspectives on the Northern Ireland Problem. Frederick W. Boal and J. Neville H. Douglas, eds.

Energy and Land Use. Robert W. Burchell and David Listokin, eds.

Slopes and Weathering. Michael Clarke and John Small.

Alaska's Rural Development. Peter G. Cornwall and Gerald McBeath, eds.

The Politics of Park Design: A History of Urban Parks in America. Galen Cranz.

World Congress on Land Policy, 1980, Proceedings. Matthew Cullen and Sharon Woolery, eds.

Oregon Divided: A Regional Geography. Samuel N. Dicken and Emily F. Dicken.

Urban Food Marketing and Third World Rural Development. T. Scarlett Epstein.

South Africa: Spatial Frameworks for Development. T. J. D. Fair.

Institutions and Geographical Patterns. Robin Flowerdew, ed.

Industrialization of U.S. Agriculture, An Interpretive Atlas. Howard F. Gregor.

Planning Theory: Prospects for the 1980s. Patsy Healy, Glen McDougall and Michael J. Thomas, eds.

Neighborhood Mobilization: Redevelopment and Response. Jeffrey R. Henig.

The American Urban System: A Geographical Perspective. R. J. Johnston.

Climate, History and the Modern World. Hubert H. Lamb.

Climate and History: Studies in Past Climates and Their Impact on Man. T. M. L. Wigley, M. J. Ingram and G. Farmer.

China: Railways and Agricultural Development, 1875–1935. Ernest P. Liang.

A Desirable Energy Future—A National Perspective. Robert S. Livingston, T. D. Anderson, T. M. Besmann, M. Olszewski, A. M. Perry, and C. D. West.

Topothesia: Essays Presented to T. S. Ó Máille. B. S. Mac Aodha, ed.

Transportation for the Poor: Research in Rural Mobility. Hal S. Maggied.

Land Uses in American Cities. Harold M. Mayer and Charles R. Haves.

Industrial Organisation and Location. Philip McDermott and Michael Taylor.

Human Adaptability: an Introduction to Ecological Anthropology. Emilio F. Moran.

Regional Analysis and the New International Division of Labor. Frank Moulaert and Patricia W. Salinas, eds.

The Nuclear War Atlas. Victoriaville, Quebec, Canada:

Urbanization and Environmental Quality. Isao Orishimo.

The Garden of Eden: The Botanic Garden and the Re-Creation of Paradise. John Prest.

Earthfire, The Eruption of Mount St. Helens. Charles Rosenfeld and Robert Cooke.

Contest for the South China Sea. Marwyn S. Samuels.

The Future of the Wetlands: Assessing Visual-Cultural Values. Richard C. Smardon, ed.

Tucson: the Life and Times of An American City. C. L. Sonnichsen.

The Geography of Multinationals. Michael Taylor and Nigel Thrift, eds.

Impact of Marine Pollution on Society. Virginia Tippie and Dana Kester.

Reviving the Industrial City: the Politics of Urban Renewal in Lyon and Birmingham. Jerry A. Webman.

Andean Reflections: Letters from Carl O. Sauer While on a South American Trip under a Grant from the Rockefeller Foundation, 1942. Robert C. West, ed.

Cartographic Drawing with Computers. P. Yoeli.  相似文献   
8.
苏鲁地体南部高压变质带岩石地球化学特征及其地质意义   总被引:6,自引:0,他引:6  
苏鲁地体南部的高压变质带由中温高压变质岩片和低温高压变质岩片两部分组成,前一岩片自下而上依次为含砾白云石英岩、云母二长石英片岩、大理岩磷块岩、白云钠长石英片岩;后一岩片的主要岩石类型为二长石英片岩钠长石英片岩。两岩片中片岩内的斜长石端员组成为钠长石,长石斑晶具有明显的火山晶屑特征,锆石具有岩浆成因韵律环带,其Th/U>0.5。此外,它们都具有高硅、高碱、低钙,轻稀土元素富集、分馏程度高,重稀土元素亏损、分馏程度低,Eu强到中度亏损及Nb、P、Ti负异常的特征,在Si O2A·R图解上均位于碱性岩区,在铝饱和指数图解中分布在偏铝质过铝质区,在(K2O Na2O)/CaO Zr Nb Ce Y图解上落在A型岩区。这些特征说明其原岩为火山岩,其岩石类型为过铝质偏铝质碱性流纹岩类,其成因类型为A型。常量元素和微量元素组成特征及其判别图解反映其原岩形成于板内拉张环境,是新元古代Rodinia大陆裂解、扬子地块陆内裂谷形成过程中伴生的产物。  相似文献   
9.
Political geography's contribution to the debate about war and peace should include re-examining traditional geopolitical concepts (e.g. heartlands, buffer zones) which apparently infuse the superpowers’ nuclear strategies. The latter contain dangerously mismatching geopolitical perspectives, which beget NATO's “flexible response” vs. total retaliation by the Warsaw Pact and the latter's view of so-called “theater” weapons like Cruise as strategic. The research agenda also needs to consider whether new weapons technology may make traditional geopolitics and current nuclear strategies obsolete.  相似文献   
10.
A series of 2D petrological–thermomechanical numerical experiments was conducted to: (i) characterize the variability of exhumation mechanisms of ultrahigh pressure metamorphic (UHPM) rocks during collision of spontaneously moving plates and (ii) study the possible geodynamic effects of melting at ultrahigh pressure conditions for the exhumation of high‐temperature–ultrahigh pressure metamorphic (HT–UHPM) rocks. To this end, the models include fluid‐ and melt‐induced weakening of rocks. Five distinct modes of exhumation of (U)HPM rocks associated with changes in several parameters in the models of plate collision and continent subduction are identified as follows: vertical crustal extrusion, large‐scale crustal stacking, shallow crustal delamination, trans‐lithospheric diapirism, and channel flow. The variation in exhumation mechanisms for (U)HPM rocks in numerical models of collision driven by spontaneously moving plates contrasts with the domination of the channel flow mode of exhumation in a majority of the published results from numerical models of collision that used a prescribed plate convergence velocity and/or did not include fluid‐ and melt‐induced weakening of rocks. This difference in the range of exhumation mechanisms suggests that the prescribed convergence velocity condition and the neglect of fluid‐ and melt‐related weakening effects in the earlier models may inhibit development of several important collisional processes found in our experiments, such as slab breakoff, vertical crustal extrusion, large‐scale stacking, shallow crustal delamination and relamination, and eduction of the continental plate. Consequently, the significance of channel flow for the exhumation of UHPM rocks may have been overstated based on the results of the earlier numerical experiments. In addition, the results from this study extend over a larger proportion of the high‐temperature range of P–T conditions documented from UHPM rocks, including those retrieved from HT–UHPM rocks, than the results of experiments from previous numerical models. In particular, the highest peak metamorphic temperatures (up to 1000 °C) are recorded in the case of the vertical crustal extrusion model in which subducted continental crust is subjected to a period of prolonged heating by asthenospheric mantle abutting the continental side of the vertically hanging slab. Nonetheless, some extreme temperature conditions which have been suggested for the Kokchetav and Bohemian massifs, perhaps up to 1100–1200 °C, are still to be achieved in experiments using numerical models.  相似文献   
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