工艺矿物学近十年的主要进展

云南思茅地区有大量难选铜锌多金属硫化矿资源,由于其矿石结构、成分及构造复杂,采用传统的镜下鉴定工艺矿物学分析对铜、锌等有价金属的赋存状态等难以自动准确定量。本文采用化学分析、偏光光显微分析及矿物解离度分析（MLA）等多种现代分析测试方法,研究该地区矿石的主要元素组成、矿物种类、嵌布和包裹特性等。分析表明,铜锌硫化矿的主要元素及含量为Cu 3.03%、Zn 3.90%、S 27.44%、Pb 0.13%。金属矿物主要是黄铁矿、黄铜矿和闪锌矿,含少量方铅矿;目的矿物黄铜矿、闪锌矿主要与黄铁矿连生和被其包裹;其次黄铜矿和闪锌矿相互连生和被其包裹,且96%以上的黄铜矿、闪锌矿和黄铁矿均分布在粒度大于9.6 μm的易选粒级范围。方铅矿多呈细粒嵌布状,与铜、锌、硫矿物之间的磨矿解离有一定困难。根据工艺矿物学研究结果,本文提出,思茅地区的铜锌硫化矿矿石需磨至约31 μm方能实现铜-锌-硫矿物的解离,需磨至约14 μm方能实现铅与其他矿物的解离,同时预测了铜锌硫化矿中铜和锌的理论选矿回收率分别为91.22%和84.92%。本文研究成果对该地区难选多金属硫化矿的选矿技术制定和指标选择具有实际的指导意义。

     

Testing a solution to the King liberation model

A solution to the King liberation model is proposed and tested against the results of King and liberation of sphalerite, galena and chalcopyrite from a complex sulphide ore. For the King data, good agreement is shown. For the complex sulphide data, the trend is correct, but calibration is required for a close fit. A potentially important use of the model solution is to predict liberation size of an ore at the exploration stage.     

Geology and the liberation of Normandy, France, 1944

The Allied victory in Europe in May 1945 marked the end of an 11-month campaign which began with the invasion of Normandy on 6 June 1944 - D-Day. Geologists participated in both the planning and operational phases of the campaign. Geological factors influenced the trafficability of the Normandy beaches, site selection for temporary airfields, quarrying for road metal and development of potable water supplies, and were also involved in ground response to aerial bombardment, vehicular movement cross-country and characteristics of both sea floor and river beds. Little-known applications of geology thus contributed to the final victory.     

A model for the quantitative estimation of mineral liberation by grinding

An exact expression is derived for the fraction of particles of mesh size D that contain less than a prescribed fraction of any particular mineral. The expression is obtained entirely in terms of the distributions of linear intercept lengths of the minerals in the ore. These distributions can be obtained by line traverses across a section of the ore. No other statistical information regarding the mineral grain sizes is required. The theory is completely free of empirical constants or other parameters and in particular no assumptions are made regarding the shape of the mineral grains in the ore or of the particles.The theory predicts that the fractional liberation of mineral at mesh size D is given by:

$\text{L(D)=1?}\text{1}\text{μ}\text{∫}\text{0}\text{D}{}_{\mathrm{u}}\text{{1?N(}\text{l}\text{D}\text{)} {2?F(l)}dl}$

where F(l) is the distribution of linear intercept lengths for the mineral and μ is the mean linear intercept length for the mineral. N(l/D) is the linear intercept distribution function for particles of mesh size D and Du is the largest intercept length across any particle of mesh size D.The theory was confirmed experimentally for the liberation of pyrite from Witwatersrand quartzite.     

Evolution of the mineral liberation characteristics of an iron ore undergoing grinding

The main objective of this experimental study was to investigate the evolution of the mineral liberation characteristics of an ore undergoing grinding. Six samples of an iron ore containing hematite, magnetite and quartz have been tested. Mineral grade and liberation measurements have been performed with an image analyser on polished sections of particles from several discrete size intervals.For each product, the grade in iron oxides was increasing greatly with the fineness of the particles. Moreover, in each size interval down to 270 mesh, it was slightly decreasing as grinding proceeded. These behaviors are due to the fact that iron oxides were ground more easily than the siliceous gangue. The degree of liberation of the valuable minerals was evidently increasing with the particle fineness. Moreover, for each size interval coarser than 48 mesh, it has also shown a slight decrease with grinding. For finer sizes however, it appeared in practice invariant and independent of the grade or of the degree of grinding. These observations are of interest when considering that the grinding products tested were very different in fineness while corresponding to various modes of fragmentation.(jaw crushing, roll crushing and ball milling) and to an ore with a high tendency to break along the mineral grain boundaries.     

Investigation of the pyrolytic liberation of molecular nitrogen from Palaeozoic sedimentary rocks

Open-system non-isothermal pyrolysis up to 1,200°C in combination with elemental analysis was used to study the thermal liberation of molecular nitrogen (N₂) from sedimentary rocks and kerogen concentrates of Palaeozoic age from the Central European Basin system and an Eocene shale (Liaohe Basin, China) with a high content (36%) of ammonium feldspar (buddingtonite). The N/C_org (atomic) ratios of the kerogen concentrates ranged from 0.005 to 0.014, which represents the range commonly observed for coals. Bulk N/C_org ratios of the Palaeozoic shales extended from 0.035 to 0.108, indicating the presence of significant amounts of inorganic nitrogen. Namurian A and A-B (CnA; CnA-B) samples typically exhibited the earliest onset of N₂ generation with intense, characteristic peaks around 600°C. N₂ liberation from the buddingtonite-rich sample occurred at higher temperatures, with a broad peak around 700°C. Pyrograms of the kerogen concentrates showed no or strongly reduced N₂ generation in the 500–700°C range. On-line isotope-specific analysis of the pyrolytically liberated N₂ on one sample revealed a variability of ∼10‰ in the δ¹⁵N values and a steady increase in δ¹⁵N with temperature during the main phase of N₂ generation.     

Oolite liberation of oolitic iron ore,Wadi Fatima,Saudi Arabia

This is an experimental work on a local oolitic iron ore deposit. The objective was to determine the operating conditions of batch rod mill operations which yield maximum liberation of the oolites from the cementing gangue minerals. The recommended operating conditions were expressed as size of crushing rods, rods/ore mass ratio and time of operation. Also calculated is Bond's constant to be used for estimating the power requirements of large mills. Scaling up of the results could be done using Gow's formula.     

可持续发展中的跨越式发展

可持续发展是国家社会为摆脱人类面临的各种危机而提出的世界总体发展战略；而跨越式发展则是发展中国家为赶上或超过世界发达国家采取的具体策略。跨越式发展不应违背可持续发展的总体要求，而可持续发展也不应限制跨越式发展的可能性和必要性，两者的协调统一是解决发达国家与发展中国家矛盾的有效方式，也是建立国际政治经济新秩序的有效手段。文章由此探讨了吉林省可持续发展可跨越式发展的相互关系。     

Windows of metamorphic sulfur liberation in the crust: Implications for gold deposit genesis

Understanding the source of metamorphic sulfur is critical to clarifying the complete cycle of ore genesis, from source to sink, for several mineral deposit types. In this study, a mass balance approach and the thermodynamic computer programs Thermocalc and PerpleX were used to constrain the P-T range of pyrite breakdown to pyrrhotite (which liberates sulfur) in common metamorphic lithologies. The results suggest that most of the continental crust’s metamorphic sulfur is liberated in a relatively narrow temperature-pressure window corresponding to the terminal breakdown of chlorite at moderate to low pressures. This is because pyrite stability is controlled partly by temperature and pressure, and partly by the amount of H₂O present. During prograde metamorphism from the greenschist to the amphibolite facies, metamorphic H₂O is produced primarily through chlorite breakdown in mafic to pelitic bulk compositions. As temperature increases, more sulfur is required from pyrite to maintain equilibrium proportions of H₂O, H₂S and SO₂ in the fluid, and in addition, progressively more sulfur is required at lower pressures. At low temperatures, little sulfur is required by metamorphic fluid released during initial chlorite breakdown, whereas at higher temperatures coinciding with the terminal breakdown of chlorite, not only is more fluid present, but the fluid’s sulfur requirement has also increased dramatically. In this way, metamorphic dehydration drives pyrite breakdown and generation of sulfur-rich hydrothermal fluids at mesothermal conditions. Beyond the chlorite stability field there is minimal metamorphic fluid production, except at low pressures and high temperatures where muscovite can break down without causing melting; conditions that are a long way from typical crustal geotherms. However, deformation also plays a key role in pyrite breakdown. Without deformation, small amounts of fluid in chemical communication with individual pyrite grains will quickly acquire equilibrium concentrations of the sulfur species and minimal pyrite breakdown is necessary. Whereas during deformation, there may be a continuous fluid flux past pyrite grains, promoting ongoing sulfur liberation. In this way, periods of deformation may be the major sulfur-liberating episodes during a metamorphic cycle. Since hydrothermal fluids are inherently buoyant and consequently tend to migrate upwards and towards cooler temperatures through the crust, these results imply that orogenic gold deposits are most likely to form at lower-amphibolite to prehnite-pumpellyite facies conditions, and unlikely to form at higher temperatures. The pressure constraint on metamorphic sulfur liberation implies that tectonic settings that allow prograde metamorphism to follow low pressure P-T-t paths in an occasionally compressional or transpressional environment are necessary. Settings that promote extensive injection of felsic magma into a mid-crust that contains a significant proportion of pyritic carbonaceous metasediment are shown to be ideal for orogenic gold deposit genesis. Inverted back-arc basins are interpreted to be the most favourable of these.     

The Welsh development agency

This paper traces the development of the concept of a regional development agency for Wales in Labour Party policy and the pressures which interacted within the policy-making structures of the party to finally create the Welsh Development Agency, set up under the Welsh Development Agency Act (1975). The influences which combined together to create the WDA are chronicled together with the policies of the agency under the three headings of industrial investment, advance factory building and land reclamation. The relationship of the WDA with other governmental organisations, and its success in creating employment and in promoting the restructuring of an economy heavily dependent on the traditional primary industries, such as coal and steel, is assessed. The work of the agency is also placed in the context of the changes which have occurred in the Welsh economy over the last few years.     

地下水管理模型研究进展

本文在分析和总结前人研究成果的基础上,将地下水管理模型的研究过程划分为两大阶段:模型理论探索到推广应用阶段(1970~1990年)和模型实用性研究阶段(1990年至今)。在对各阶段的研究内容以及存在问题等进行概述的基础上,指出建立地下水资源管理的多目标动态规划模型将是未来地下水管理模型的发展方向和趋势,但需要采用更为先进的优化算法对其进行求解,同时对地下水管理模型与GIS技术的集成进行了展望。     

The regional development problems of Transcaucasia

This article examines the economic development of three distinctive republics (Georgian S.S.R., Armenian S.S.R., Azerbaydzhan S.S.R.) on the periphery of the U.S.S.R. Planned as three republican territorial production complexes, they have recently undergone considerable industrialization with growing integration of their economies. Increasingly urban, environmental and social problems associated with development have become more prominent in the planning process.     

The development of warehousing in England

Over the past decade there has been a growing recognition by the business community, central government and local planners of the economic importance of warehousing. This importance can be measured in terms of the value of stock held in warehouses, their very rapid growth relative to other types of commercial property and the employment they create. This article reviews changes in business and planning attitudes to warehousing, accounts for the recent growth of warehouse floorspace in England and examines the spatial distribution of this growth.     

The development of India's mining industry

This paper evaluates the development of India's mining industry, its present status and future outlook. Despite its growth, the contribution of India's mining industry to GDP has remained relatively stable since 1970. At present the nation is a leading world producer of 11 major mineral and energy commodities, including bauxite, chromite, coal, iron ore and manganese. Recent economic reforms have stimulated industrial expansion in India; however, problems, including a restricted private sector role in resource development and ineffective government mineral strategies, may limit future growth in output. Capital investment levels in India's mining industry are examined in the paper to assess possible long-term expansion levels.     

GPS技术的进一步发展及应用探讨

GPS作为一种新技术,其要得到进一步发展和应用,必须突出GPS技术的内涵性和外延性两个方面,通过在硬件及软件的不断更新发展,以及与其他技术的整体集成,GPS的应用前景必将更加广阔,进一步向着精确化、普遍化、实用化、系统化、定量化和数字化的方向发展。     

The structure and development of greater Lagos

In the period between 1965 and 1976, when German geographers carried out their fieldwork for the Afrika-Kartenwerk under the sponsorship of the German Research Society, remarkable progress in urban development especially in Lagos could be observed. The cooperation with the Federal Survey Department of Nigeria gave the opportunity for collecting several series of aerial photographs which bring into focus some stages of the overwhelming urban expansion.The materials presented here have been selected to demonstrate some regional structures of the Nigerian capital. — In the geography of today the scientific evaluation of aerial photographs together with findings from local observation and historical as well as statistical data is still undervalued. Through this technique, the more classical and conservative method of geographical analysis, relying on subjective judgement, may regain some of its importance, which it once had in the age of exploration of new territories.Where data is scarce and written records of urban expansion are not available or difficult to extract, aerial photographs can give an impression of certain stages of urban growth. A functional analysis under geographical aspects has to be regarded by changes within spatial units in order to the factors of influence. Those factors are numerous, their influence will cause changes in a series of pushes arising from economic developments of the vast hinterland as well as from social conditions of certain groups of the population. In a metropolitan center, as Lagos, the highest ranking central place of Africa's most populous nation, heterogenous events and a confusing number of planning decisions must be taken into consideration. One consequence of nationwide regional interactions with the metropolis is migratory population dynamics. In pursuing lines of interaction, which originate from economic power, population density, and natural resources, one can hardly isolate a single element of influence because all factors are closely interrelated. For Lagos, there is only limited data available on the social and economic standard of the population, valid basic demographic figures of some value are not available.One still has to accept very rough estimates on population figures, number of industrial workers, the standards of housing and the social and economic hierarchy of the population. The present retrospective analysis of aerial photographs gives an interpretation of the regional structure of the town and indicate possible future development.     

The development of geological structures in China

China is situated in the SE part of the Asian Continent, occupies a region where several intercontinental tectonic elements are superposed on one another. In the history of geology, China belongs largely to the North Continent, except for the Himalaya region lying on the N edge of the Indian massif of the South Continent. The greater part of the Oing-hai-Xizang Plateau (Chinghai-Tibet Plateau) belongs to the middle segment of the huge-type Tethys tectonic zone, and the E part of China belongs to the Circum-Pacific tectonic zone of the Meso-Cenozoic era.According to Guo Wenkui six stages of the geological development in China may be distinguished (Guo 1978). The author has absorbed some of his views and data in this paper, and taking the three tectonic movements: The Lüliang, the Jinning and the Indonesian movements as the turning points has summarized the evolution of geologic structures in China into four mega-stages: 1) the Pre-Lüliang stage, 2) the Lüliang-Jinning stage, 3) the Jinning-Indonesian stage, and 4) the Post-Indonesian stage. Some information of the regional geologic survey and results of specific studies, and also the unpublished data obtained from the colleagues of the Institute of Geology, especially the final stratigraphic materials, have been made references to during the preparation of this paper. The author wishes to express his thanks to all who have given him generous aid.     

The development of orientated symplectites during deformation

Abstract Orientated symplectites have been observed in deformed granulite facies metabasic rocks from the Ivrea-Verbano zone in northern Italy. The area underwent lower crustal extension, accommodated by movement on localized high- T shear zones. In areas of relatively low strain, such as at the margins of shear zones, symplectites of orthopyroxene, plagioclase and spinel have formed. The symplectites are vermiform and orientated parallel to the main foliation and in the regional stretching direction. The reaction was synkinematic with the deformation, and only developed in potentially dilatant grain boundaries in the rock. It was presumably inhibited in grain boundaries subjected to higher normal stress due to the relatively large volume increase involved in the reaction.
The observations support the interpretation that the deformation was related to regional extension under high- T granulite facies conditions, the symplectites forming as a result of decreasing pressure.