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951.
官房钨矿床位于滇东南薄竹山W多金属矿集区,是近年来新发现的大型白钨矿床。矽卡岩多产于层间破碎带,呈似层状、透镜状和脉状,一般不与花岗岩体接触而形成远端矽卡岩(深部揭露有少量产于接触带),矽卡岩矿物发育。为进一步查明矽卡岩矿物学和矿物化学特征,揭示矽卡岩形成环境,探讨矽卡岩与矿化类型之间的关系,笔者采集了KT3近端矽卡岩与KT5远端矽卡岩进行对比,通过开展系统的矿物学镜下观察,利用EMPA进行石榴子石成分分析,LA-ICP-MS对典型的矽卡岩矿物进行了单矿物分析。研究表明,官房钨矿床矽卡岩属典型钙质矽卡岩,矽卡岩矿物主要有石榴子石、辉石、符山石等,其中石榴子石为钙铝榴石-钙铁榴石系列,辉石为透辉石-钙铁辉石系列,符山石属普通符山石。由近端矽卡岩向远端矽卡岩,石榴子石主要成分由钙铝榴石向钙铁榴石转化;辉石几乎全部为透辉石向透辉石、钙铁辉石的组合转化,石榴子石与辉石的特征表明矿床的矽卡岩由还原型矽卡岩转为氧化型矽卡岩;KT5形成条件较KT3氧逸度更高,两者流体交代方式以扩散交代为主。石榴子石、辉石端员组分及Mn/Fe、Mg/Fe比值稍高的特征,综合指示其矿化类型属于铁铜锌等多金属矿化类型;符山石中较低的w(W)可作为钨矿找矿标志。  相似文献   
952.
Forward and inverse mineral equilibria modelling of metapelitic rocks in the hangingwall and footwall of the Plattengneiss, a major shear zone in the Eastern Alps, is used to constrain their tectonometamorphic evolution and assess models for their exhumation. Forward (pseudosection) modelling of two metapelitic rocks suggests a steep clockwise P–T path with a near‐isothermal decompression segment from a pressure peak at ~18–19 kbar and 670 °C to the metamorphic peak at 680–720 °C and 11–13 kbar. A subsequent decrease to 600–645 °C and 8–9 kbar is inferred from the late growth of staurolite in some samples. Conventional thermobarometric calculations (inverse modelling) on 18 samples with the inferred peak assemblage garnet + plagioclase + muscovite + biotite + quartz + rutile ± ilmenite ± kyanite are associated with large 2σ uncertainties, and absolute pressures calculated for all samples are statistically indistinguishable. However, calculations constraining relative pressure differences (ΔP) between samples sharing a common mineral assemblage are associated with much smaller uncertainties and yield pressure differences that are statistically meaningful. Although the overall pattern is complicated, the results suggest a pressure gradient of up to 3 kbar across the shear zone that is consistent with volume loss and a model of exhumation related to slab extraction for the Plattengneiss shear zone.  相似文献   
953.
Aims and Scopc     
正Being an international journal,China Ocean Engineering takes as its prime function the integration of nev\research concepts,equipment,technology,materials and structures and olhcr scientific advances within the field of cstuarial.coastal.ot Tshorc.and deepwater engineering with particular reference to developments.The Journal is conccrncd with all engineering  相似文献   
954.
Abstract

Mineral matter in coals has been found to host valuable elements including germanium, lithium and rare-earth elements (REE), but such content of Australian coals remains under-explored. The aim of this paper is to provide a proof-of-concept study that determines elemental concentrations in the mineral matter of the high-ash, Fort Cooper Coal Measures (FCCM), Bowen Basin, Queensland. Coal in the FCCM has good coking properties but has not been extensively explored owing to its high ash content. This study performs a preliminary assessment of the elements from the coal portion that would typically become waste after washing or combustion. Given that the needs for industrial extraction methods will change over time, cataloguing and documenting the elemental composition of coal may assist future development of multiple products for the benefit of both the coal and mineral industries. This preliminary study has revealed similar elevations of REE and higher-than-average crustal concentrations of lithium, bismuth and scandium in some of the samples. Further analyses will be required on a larger dataset to better understand elemental associations and explore spatial patterns of elemental content that may indicate localised enrichments. Understanding the potential of valuable elements in the FCCM may stimulate interest in multiple-product-coal (or elemental-coal) mining in this under-exploited resource and further encourage the reduction of waste from other Australian coals at the wash-plant stage.  相似文献   
955.
崔海 《吉林地质》1993,12(4):42-54
本文对山门银矿矿体及围岩中黄铁矿进行了成因和找矿矿物学特征的研究,并在矿床研究方面和找矿方面得到应用。  相似文献   
956.
通过不同类型中低品位铝土矿选矿试验结果,论述了河南铝土矿选矿的必要性和可行性。中低品位铝土矿开发的趋势就是走选冶结合的道路,这将是铝工业发展的必然。  相似文献   
957.
BOOK REVIEWS     
Books Reviewed in this article: Lob Trees in the Wilderness . Clifford and Isabel Ahlgren . Satellite Microwave Remote Sensing . T. D. Allan , ed. Sunbelt Cities: Politics and Growth Since World War II . Richard M. Bernard and Bradley R. Rice , eds. Legacy of Minneapolis: Preservation Amid Change . John R. Borchert , David Gebhard , David Lanegran , and Judith A. Martin . Bloomington, MN: Preparing a Historic Preservation Ordinance. Richard J. Roddewig . The Mountains of Northeastern Tasmania, A Study of Alpine Geomorphology . Nel Caine . Introductory Cartography . John Campbell . Englewood Cliffs, NJ: Changing Climate . Manual of Remote Sensing, Second Edition . 2 Vols. Robert N. Colwell , ed.-in-chief; David S. Simonett and John E. Estes , vol. eds. Remote Sensing in Meteorology, Oceanography and Hydrology . A. P. Cracknell , ed. Multidimensional Scaling . Mark L. Davison . Environmental Karst . Percy H. Dougherty , ed. The Urban Environment . Ian Douglas . Geomorphology of Europe . Clifford Embleton , ed. An Introduction to South Asia . B. H. Farmer . Great Geological Controversies . A. Hallam . Hazardous Waste Management: In Whose Backyard? Michalann Harthill , ed. Energy for Subsistence . Margaret Haswell . Perspective on Ratzel's Political Geography . James M. Hunter . Economic Deposits and their Tectonic Setting . Charles S. Hutchison . Energy Risk Assessment . Herbert Inhaber . Discovering the Vernacular Landscape . John Brinckerhoff Jackson . Climate and Energy Systems: A Review of Their Interactions . Jill Jäger . Dilemmas in Regional Policy . Antoni Kuklinski and J. G. Lambooy , eds. California Farmland: A History of Large Agricultural Landholdings . Ellen Liebman . The Spatial Organization of New Land Settlement in Latin America . Jacob O. Maos . Dark Continent: Africa as Seen by Americans . Michael McCarthy . Westport, CT: Climatology: An Introduction . John E. Oliver and John J. Hidore . Columbus, OH: The Geography of Warfare . Patrick O'Sullivan and Jesse W. Miller . The Expanding City. Essays in Honour of Professor Jean Gottmann . John Patten , ed. Scotland's Environment During the Last 30,000 Years . Robert J. Price . Integrated Urban Models . S. H. Putman . Development and the Environmental Crisis: Red or Green Alternatives? Michael Redclift .  相似文献   
958.
The Dempster-Shafer theory has been successfully applied to mineral resource potential mapping in G1S environmental. In this applied form, basic probability assignment and combined basic probability assignment are applied to measuring map pattern and map pattern combination, respectively; and the environment composed of the only two singleton sets (deposit set and non-deposit set), is used for expressing the entire map area. For a subarea in which the certain map pattern combination exists, the combined basic probability assignment corresponding to the map pattern combination existing in this subarea, expresses the belief of inferring the subarea belonging to the deposit set from the evidence that the corresponding map pattern combination existing in the subarea. Thus, it may be served as a statistical index measuring the relative mineral resource potentials of the subarea. And it may be determined like 1) dividing the map area into a series of small equal-sized grid cells and then select the training sample set composed of the well-known grid cells or the entire grid cells; 2) estimating the basic probability assignments corresponding to each map pattern from the training sample set; 3) determining the map pattern combination existing in each cell, and then appling the Dempster's Rule of Combination to integrating the all basic probability assignments corresponding to the map patterns existing in the cell into the combined basic probability assignment. Mineral resource potential mapping with the Dempster-Shafer theory is demonstrated on a case study to select mineral resource targets. The experimental results manifest that the model can be compared with the weights of evidence model in the effectiveness of mineral resource target selection.  相似文献   
959.
BOOK REVIEWS     
Books reviewed in this article: The Mexican Colonial Copper Industry. Elinore M. Barrett . The Control Revolution: Technological and Economic Origins of the Information Society . James R. Beniger . Land Degradation and Society . Piers M. Blaikie And Harold C. Brookfield , Eds . La carte, mode d'emploi. Roger Brunet . France: les dynamiques du territoire . Roger Brunet AND Jacques Sallois , EDS. At the Crossroads—The Mineral Problems of the United States . Eugene N. Cameron . A Census of One Billion People , Papers for International Seminar on China's 1982 Population Census. Li Chengrui , ED. Les Milieux “Naturels” du Globe . Jean Demangeot . The Geophysiology of Amazonia: Vegetation and Climate Interactions : Robert E. Dickinson , ED. Tenn-Tom Country . James F. Doster And David C. Weaver . Family Farming in Europe and America . Boguslaw Galeski And Eugene Wilkening , EDS. The Geography of Urban Transportation . Susan Hanson , Ed. Combating Desertification in Developing Countries . J. K. Jain , ED. Cartography in France—1660–1848. Science, Engineering and Statecraft . Josef W. Konvitz . Distribution of Distances in Pregeographical Space . Hans Kuiper . Physical Geography Lab Manual: A New Experimental Approach . Neal G. Lineback And John M. Harlin . Physical Geography: A Landscape Appreciation , 2nd ed. Tom L. Mc Knight . The Desert Is No Lady: Southwestern Landscapes in Women's Writing and Art . Vera Norwood And Janice Monk , EDS. France: A Geographical, Social, and Economic Survey . Philippe Pinchemel , translated, by D. Elkins and T. H. Elkins. Gene Banks and the World's Food . Donald L. Plucknett , Nigel J. H. Smith , J. T. Williams , And N. Murthi Anishetty . Latin American Development: Geographical Perspectives . David Preston , Ed. Making Sense of Development: An Introduction to Classical and Contemporary Theories of Development and Their Application to Southeast Asia . P. W. Preston . The History of the Countryside. Oliver Rackham . The Third World in Perspective . H. A. Reitsma AND J. M. G. Kleinpenning . The Industrial Geography of Australia . David C. Rich . The Recruiting Game , 2nd Ed., revised. John F. Rooney , JR. A Cultural Geography of North American Indians . Thomas E. Ross AND Tyrel G. Moore , EDS. Eastern Europe . Dean S. Rugg . Human Territoriality: Its Theory and History . Cambridge Studies in Historical Geography: 7. Robert David Sack . Experimental Fluvial Geomorphology . Stanley A. Schumm , M. Paul Mosley , AND William E. Weaver . The New Urban Landscape . David Schuyler . Atlas of American Women . Barbara Gimla Shortridge . Impacts of Hazardous Technology: The Psycho-Social Effects of Restarting TMI-1 . John Sorensen , Jon Soderstrom , Emily Copenhaver , Sam Carnes AND Robert Bolin . Modern Physical Geography , 3rd Ed., (Third Edition). Arthur N. Strahler AND Alan H. Strahler . India: Economic Resource Base and Contemporary Political Patterns . B. L. Sukhwal .  相似文献   
960.
我国蛇绿岩分布广泛。蛇绿岩中有着成因上和时空上紧密联系的一系列非金属矿床,它们构成了蛇绿岩建造非金属矿床成矿系列。这一成矿系列中的主要非金属矿有橄榄岩、玄武岩、蛇纹岩、石棉、滑石、玉石类等等,主要的成矿作用有岩浆作用、接触变质作用、交代蚀变作用等。其成矿作用和矿床分布模式有明显规律,这些规律对于地质勘查、资源开发等都具有重要的意义。  相似文献   
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