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861.
新疆坡北基性-超基性岩带1号岩体地质特征及其含矿性研究 总被引:3,自引:0,他引:3
坡北1号岩体是幔源基性岩浆以深部分异多次侵入和结晶分异两种方式形成的基性-超基性复式岩体。该岩体属于橄榄辉长岩—橄榄单辉岩—单辉橄榄岩型,规模较大,分异良好,地表发现铜镍硫化物矿化带。与国内已知含矿岩体对比,1号岩体的类型、岩石化学特征、有用组分含量和地表矿化特征都在含铜镍硫化物矿体的变化范围之内。物探测量结果显示深部存在低阻高激化体。因此,1号岩体是坡北岩带中寻找铜镍硫化物矿床远景很好的岩体。 相似文献
862.
中国地区地磁异常与地震分布关系 总被引:3,自引:0,他引:3
本文用1970.0年全国地磁普测的归化值,减去按国际地磁参考场(IGRF1985)计算的中国地区地磁正常值,得到地磁异常,绘制了异常等值线图,进而对我国大陆地磁异常分布的特点进行分析,发现地磁异常展布格局与地质构造格局相当吻合,地磁异常与地震分布有着密切的关系。 相似文献
863.
本文综述了液态包裹体压碎法的机理以及该方法在寻找热液型金矿中的应用,例举了用该方法判别岩石的含金性、圈定蚀变晕的空间位置等方面的实例。 相似文献
864.
《The Professional geographer》1984,36(1):106-142
Book Reviewed in this article: Development and Environment in Peninsular Malaysia . S. Robert Aiken, Colin H. Leigh, Thomas R. Leinbach, Michael R. Moss. The Rural-Urban Fringe: Canadian Perspectives . Ken B. Beesley and Lorne H. Russwurm, eds. Women and Development . Lourdes Benería, ed. The Border that Joins: Mexican Migrants and U.S. Responsibility . Peter G. Brown and Henry Shue, eds. Cities of the World: World Regional Urban Development . Stanley D. Brunn and Jack L. Williams, eds. Time Resources, Society, and Ecology: On the Capacity for Human Interaction in Space and Time (Vol. I, Preindustrial Societies). Tommy Carlstein. Urban Geography . David Clark. Spanish City Planning in North America . Dora P. Crouch, Daniel J. Garr, and Axel I. Mundigo. Not On Our Street: Community Attitudes to Mental Health Care . M. J. Dear and S. M. Taylor Unequal growth: Urban and Regional Employment Change in the U.K. Stephen Fothergill and Graham Gudgin. Agricultural Land in an Urban Society . Owen J. Furuseth and John T. Pierce. The Petroleum Industry in Oil-Importing Developing Countries . Fariborz Ghadar. Historical Understanding in Geography, An Idealist Approach . Leonard Guelke. Regional Planning in Europe . R. Hudson and J. R. Lewis, eds. Remote Sensing for Resource Management . Chris J. Johannsen and James L. Sanders, eds. Geography and The State . R. J. Johnston. Texas Graveyards: a Cultural Legacy . Tlrry G. Jordan. The Politics of Location: An Introduction . Andrew Kirby. A Social Geography of the City . David Ley. Energy and the Future . Douglas MacLean and Peter Brown, eds. The Natural Environment of Newfoundland Past and Present . A. G. Macpherson and J. B. Macpherson, eds. Tourism: Economic, Physical and Social Impacts . Alister Mathieson and Geoffrey Wall. Railroads and Land Grant Policy: A Study in Government Intervention . Lloyd J. Mercer. Progress in Rural Geography . Michael Pacione, ed. Progress in Urban Geography . Michael Pacione, ed. Models of Spatial Inequality: Settlement Patterns in Historical Archaeology . Robert Paynter. Natural Hazard Risk Assessment and Public Policy, Anticipating the Unexpected . William J. Petak and Arthur A. Atkisson. The Nature of Geomorphology . Alistair F. Pitty. Regional Conflict and National Policy . Kent A. Price Women and Spatial Change: Learning Resources for Social Science Courses . Arlene C. Rengert and Janice J. Monk, eds. Urban and Regional Analysis for Development Planning . Richard Rhoda. Rivers: Form and Process in Alluvial Channels . Keith Richards. This Remarkable Continent: An Atlas of United States and Canadian Society and Culture . John F. Rooney, Jr., Wilbur Zelinsky, and Dean R. Louder, gen. eds. The Origins of Open-Field Agriculture . Trevor Rowley, ed. Residential Location Determinants of the Older Population . Gundars Rudzitis. Borderland Sourcebook: A Guide to the Literature on Northern Mexico and the American Southwest . Ellwyn R. Stoddard, Richard L. Nostrand, and Jonathan P. West, eds. Arctic and Antarctic . David Sugden. Tall Timbers Ecology and Management Conference, February 22–24, 1979, Proceedings No. 16 . Graphic Communication and Design in Contemporary Cartography (Progress in Contemporary Cartography , Vol. II). D. R. Fraser Taylor, ed. Living with Energy Shortfall: A Future for American Towns and Cities . Jon Van Til. The United States: Habitation of Hope . J. Wreford Watson. Air Photo Interpretation for Archaeologists . D. R. Wilson. Urban and Rural Change in West Germany . Trevor Wild, ed. Population and Resources . Harry Robinson. 相似文献
865.
The man-induced sediment disaster includes material erosion, transportation and accumulation by human activities. It possesses
special attribute in sociology and disaster science. In accordance with human activities, geomorphologic location, behavior
and particular, the man-induced sediment disaster can be divided into 4 types: the drainage network, slope and gully, channel
and plain-estuary-coastline. Each type includes erosion, transportation, accumulation, complexity and cascading. Based on
human activity, geomorphology, sediment mechanics and catastrophology, the man-induced sediment disaster is characterized
as follows: (1) accelerating tendency with geographical zoning back-ground; (2) non-order characters by blind action without
special technical training; (3) gradually and sharply changing with human environment vibration; and (4) complexity and non-linear
figure, etc. One of the reasons leading to man-induced sediment disaster is human environment vibration. 相似文献
866.
Composition and distribution of organochlorine pesticide residues in surface sediments from the Wu-Shi River Estuary,Taiwan 总被引:23,自引:0,他引:23
The contamination of organochlorine pesticides (OCPs) in sediments from the Wu-Shi River estuary was investigated to evaluate the pollution potentials and distribution of OCPs in central Taiwan. A total of 19 sediment samples were collected at five sampling stations along the River estuary. The concentrations of OCPs were in the range of 0.99–14.5 ng/g-dry weight (dw) for ΣHCH (-, β-, γ-, δ-HCH), 0.46–13.4 ng/g-dw for Σcyclodiene and 0.53–11.4 ng/g-dw for ΣDDT (p,p′-DDD, p,p′-DDE, p,p′-DDT). The mean concentrations of ΣHCH, Σcyclodiene and ΣDDT were 3.79, 4.87 and 2.51 ng/g-dw, respectively. The total concentrations of OCPs correspond to 1.73–71.9 μg/g-OC when normalized to TOC contents. Among the organochlorine pesticides, endosulfan sulfate, β-HCH, and p,p′-DDD were the most dominant compounds in the sediments with the average concentrations of 1.97, 3.43 and 2.08 ng/g, respectively. Also, different contamination patterns among sampling seasons were observed. The measured concentrations of OCPs collected in spring were higher than those in autumn and winter. A linear relationship between sediment characteristics and OCP residues was also demonstrated. The results obtained in this study show that there still exist a variety of organochlorine pesticide residues in the sediments from the near shore of central Taiwan. 相似文献
867.
868.
大骨结病是中国分布较广的地方病,在四川省阿坝州流行,特别在若尔盖的包座地区严重流行。笔者通过以往专家对于大骨结病病因研究、生命元素特征分析和大骨结病病区和非病区的元素背景的研究认为,四川阿坝地区大骨结病可能是病区腐植酸富集,Se、Mo、Cu、V的偏低和Ba、Sr、P对于CaO的拮抗作用造成Ca的缺乏所引起的地方病。与此同时,通过1:20万内江幅“趴病”区的土壤和水化学元素地球化学研究,认为有类似之处。因此,上述因素可能是这种骨骼病的地球化学的病因。 相似文献
869.
大青山金矿床位于北山古生代裂谷系,呈脉状、透镜状产于石炭系下统红柳园组下亚组含炭碎屑岩中,骆驼峰-大青山-险峰断裂带及其派生的断裂组为其提供了有利的导矿、容矿空间.矿化体中金的富集与石英脉的空间分布、矿石的结构构造、金属硫化物的含量、粒度有着密切的关系. 相似文献
870.
铜官山铜矿床是我国著名的铜产地,首次在罗村矿段圈定出具有工业意义的金矿体,是铜官山矿区找矿工作的一个突破.通过野外勘查分析得出金矿体主要赋存在矽卡岩、大理岩及闪长岩交汇处的次级小断裂或裂隙中,受岩浆岩、地层的岩性、接触带构造及次级小断裂或裂隙等多种因素控制,而金大量析出则发生在热液后期的碳酸盐阶段。 相似文献