A behavioural analysis of hop farming in Hereford and Worcestershire

Behavioural studies in agricultural geography are comparatively rare, and this paper demonstrates the importance of the satisficer concept of economic behaviour when examining patterns of hop production in the West Midlands. The main farm and farmer characteristics of the hop growers are outlined before attention is focused on the relative importance of physical, economic and socio-personal factors in the decision-making process. Whilst economic factors dominate the ranking, socio-personal factors have a significant effect on the hop growers' decision-behaviour. Opportunity cost and social inertia are forwarded as important concepts in accounting for patterns of hop farming and a multivariate analysis emphasized the complexity and individuality surrounding farmers' decision-making behaviour. Differences in attitudes and behaviour are shown to be related to variations in the hop farmers' personality and rationality and to differences in their age, education, experience and traditions.     

A review of sandstone illite cements and aspects of their significance to hydrocarbon exploration and development

Current understanding of the origin of illite cements within the pore systems of sandstone reservoirs is at best speculative whilst knowledge of the control of illite morpholoy is, to all practical purposes, non-existent. This is unfortunate considering the widespread occurrence of illite and the often disastrous decrease in reservoir performance associated with its presence (up to 200-fold decreases in permeability have been recorded from aeolian sandstones of the U.K. southern North Sea for example). An advanced knowledge of the origin of this clay mineral is thus of considerable importance to the future of the hydrocarbon exploration and production industry. This paper presents an assessment of sandstone illite morphotypes and reviews the mechanisms which have been proposed for their formation.     

Energizing historical materialism: Fossil fuels, space and the capitalist mode of production

In this paper, I present a theoretical argument that fossil fuel represents a historically specific and internally necessary aspect of the capitalist mode of production. Despite sustained attention to distributional conflicts between international capital and energy rich nation-states, few historical-materialists have paid attention to the relations between fossil fuel and capital accumulation in industrial capitalist societies. In opposition to ecological economic notions of fixed thermodynamic “laws”, I first propose a dialectical conception of energy as embedded in dynamic social processes and power relations. Second, I review the historical importance of the energy shift from solar or biological sources of energy (muscles, wind, and water) to fossilized sources of energy (coal, oil, and gas). I then demonstrate how attention to fossil fuel energy forces a reexamination of the core insights of ecological Marxism and the political economy of nature. In the core argument of the paper, I reconsider the shift from biological to fossil energy as internal to the generalization and extension of capitalist social relations from two basic vantage points - (1) capitalist production based on wage labor; (2) the spatial conditions of capitalist circulation. I conclude by asking whether it is accurate to conceptualize capitalism as a “fossil fuel mode of production” and highlight the political urgency of a historical materialist perspective that takes seriously the importance of energy to the reproduction of capitalist social relations.     

Relation between U-series nuclide migration and microstructural properties of sedimentary rocks

Natural radionuclide migration in Miocene sedimentary rocks has been studied at the Tono U deposit in Japan, which is a potentially useful analogue of radioactive waste isolation in geological environments.Uranium series disequilibrium studies have revealed that natural radionuclides have been redistributed during the past 3.5 × 10⁵ a in the U-mineralized zone. Permeability tests using core samples of the U-mineralized zone have shown that the microfabrics of sedimentary rocks, such as the connectivity of pores which control the groundwater movement, directly influence the redistribution of nuclides.Detailed observations using cathodoluminescence (CL) and electron probe microanalysis (EPMA) were carried out after a dye-impregnation test in order to improve the understanding of the importance of microfabrics in relation to nuclide migration. Results of the observations show that U has migrated within detrital grains, such as biotite and quartz, as well as between these grains. Uranium-series disequilibrium studies of each detrital quartz and biotite grain have been shown that these detrital minerals behave differently in respect of the migration of U, owing to their different textural properties. The detrital biotite flakes, especially along the (001)-cleavage planes, appear to have fixed U for a long period of time, whereas the U has remained mobile within the microfractures in detrital quartz grains.     

Trace element compositions of submicroscopic inclusions in coated diamond: A tool for understanding diamond petrogenesis

Trace element compositions of submicroscopic inclusions in both the core and the coat of five coated diamonds from the Democratic Republic of Congo (DRC, formerly Zaire) have been analyzed by Laser Ablation Inductively Coupled Mass Plasma Spectrometry (LA-ICP-MS). Both the diamond core and coat inclusions show a general 2-4-fold enrichment in incompatible elements relative to major elements. This level of enrichment is unlikely to be explained by the entrapment of silicate mantle minerals (olivine, garnet, clinopyroxene, phlogopite) alone and thus submicroscopic fluid or glass inclusions are inferred in both the diamond coat and in the gem quality diamond core. The diamond core fluids have elevated High Field Strength Element (Ti, Ta, Zr, Nb) concentrations and are enriched in U relative to inclusions in the diamond coats and relative to chondrite. The core fluids are also moderately enriched in LILE (Ba, Sr, K). Therefore, we suggest that the diamond cores contain inclusions of silicate melt. However, the Ni content and Ni/Fe ratio of the trapped fluid are very high for a silicate melt in equilibrium with mantle minerals; high Ni and Co concentrations in the diamond cores are attributed to the presence of a sulfide phase coexisting with silicate melt in the diamond core inclusions. Inclusions in the diamond coat are enriched in LILE (U, Ba, Sr, K) and La over the diamond core fluids and to chondrite. The coats have incompatible element ratios similar to natural carbonatite (coat fluid: Na/Ba ≈0.66, La/Ta≈130). The coat fluid is also moderately enriched in HFSE (Ta, Nb, Zr) when normalized to chondritic Al. LILE and La enrichment is related to the presence of a carbonatitic fluid in the diamond coat inclusions, which is mixed with a HFSE-rich hydrous silicate fluid similar to that in the core. The composition of the coat fluid is consistent with a genetic link to group 1 kimberlite.     

Economics of the coal industry east of the Mississippi, 1973–1982

Government regulations on health, safety and environment have been poppular blamed for the declining productivity in U.S. coal mines since 1970. The stagnation in the coal industry east of the Mississippi is alleged to have been caused by this declining productivity and by the growth of cheaper and cleaner coal production west of the Mississippi. Economic evidence suggests, however, that productivity declines were more due to a relative lowering of labor costs in comparison with coal prices and due to work stoppages. The development of western coals fields was spurred by growth in local demand and had only a relatively small impact on coal production east of the Mississippi. Problems of the eastern coal industry are rooted mainly in slow economic growth in eastern U.S. which must be addressed in the long-term interests of the eastern coal industry.     

纯铁状态方程第一原理计算与外核密度亏损

本文利用第一原理计算了0K下铁磁性对铁状态方程的影响,计算了0K下纯铁的状态方程,通过与实验数据的比较,发现GGA更适合描述铁在高温高压下的状态方程.在此基础上,利用第一原理分子动力学方法模拟了外核条件下的液态铁,模拟温度从5000K到7000K,计算出内外核边界处的外核密度亏损值对应5000K的熔化温度时是8.9％,...     

High radiogenic heat production in the Kerala Khondalite Block,Southern Granulite Province,India

In situ radioelemental (K, U and Th) analysis and heat production estimates have been made at 59 sites in the Kerala Khondalite Block (KKB) of the Southern Granulite Province (SGP) of India. Together with the in situ analyses on granulites and gneisses previously reported from 28 sites, and heat production estimated from the published geochemical analyses on granites and syenites of the KKB, the new data set allows good characterization of heat production for the major granulite facies rocks and granitoids of the KKB. Garnet biotite gneisses are characterized by high levels of Th and U, with mean values of 60 and 3 ppm, respectively. Khondalites, leptynites and charnockites have slightly lower levels of Th (23, 20 and 22 ppm, respectively) and U (2.9, 2.4 and 0.9 ppm, respectively). The mean K, U, Th abundances for the granites, leucogranites and granitic gneisses ranges from 3.9 to 4.3%, 2.6 to 4.3 ppm, 22 to 50 ppm respectively, and for the syenites 4.8%, 2 ppm and 5.7 ppm. Mean radiogenic heat production values for garnet–biotite gneiss, khondalite, leptynite and charnockite are 5.5, 2.7, 2.4 and 2.2 μW m⁻³, respectively. For the granites, leucogranites, granitic gneisses and syenites it is 2.6, 3.4, 4.6 and 1.4 μW m⁻³, respectively. Heat production of granulite facies rocks, which are the most abundant rocks in KKB, correlate well with Th, but less with U, suggesting that variation is caused by Th and U bearing accessory minerals such as monazite and zircon. The high heat production of the KKB granulites are in contrast to the low heat production of the Late Archaean granulites of the Northern Block (NB) of the SGP which are highly depleted in radioelements and also the granulites of Madurai Block (MB) that have higher radioelemental abundances than in the granulites of the NB. The high heat production of the KKB granulites could be due to the nature of protoliths and/or metasomatism associated with Neoproteroic- to- Pan African alkaline magmatic activity represented by alkali granite and syenite–carbonatite emplacements and emplacement of pegmatites.     

世界稀土产业格局变化与中国稀土产业面临的问题

稀土元素在永磁材料等新材料领域有着广泛的应用,被世界各主要国家列为战略资源.从资源、生产格局上看,近年来随着世界范围内稀土探矿热潮的出现以及中国稀土资源的大量开发,中国稀土资源优势地位正逐渐降低;美国等西方国家大力推动中国之外稀土矿山和冶炼分离项目的建设,全球稀土生产格局或将发生变化.从消费方面看,稀土消费可被归为永磁...     

History of actinide and minor element mobility in an Archean granitic batholith in Manitoba,Canada

Surface and borehole core samples from the Lac du Bonnet granite, Manitoba, Canada, have been analysed for major element concentrations,Fe³⁺/Fe (total) ratios, rare earth element (REE) content and actinide isotopic abundances. This work forms part of the geological investigations of the Canadian Nuclear Fuel Waste Management Program, performed by Atomic Energy of Canada Limited (AECL). The study attempts to understand the history of, and processes governing, mobilisation of elements and naturally occurring radionuclides during high- and low-temperature alteration events in fluid-bearing fractures in the granite.One surface sample and two core samples (from ∼ 150 m and 730 m) are each in contact with fractures in the granite and show evidence of alteration events that penetrated the rock matrix over distances of at least 3 cm. Loss of Ca and Na is seen in cores from a depth of ∼ 150 m from the highly altered, hematite-rich rock adjacent to sub-horizontal fracture zones at the Underground Research Laboratory (URL) of AECL, near Lac du Bonnet. In contrast, K, Fe,Fe³⁺/Fe and U concentrations increase towards the fracture surface due to formation of illite and association of U with hematite and the illite. At the fracture surface, U continues to increase, but Fe and theFe³⁺/Fe ratio decrease indicating Fe removal by reduction. The REE also show some enrichment in more altered rock at intermediate depths, but the total REE concentration is lower than in the surface and deep core samples. No clear trends are visible for parent and fracture-surface REE in surface and deep core samples, however.Disequilibrium values of²³⁴U/²³⁸U and ²³⁰Th/²³⁴U ratios in surface and intermediate depth core samples indicate that U has been mobilised in recent geological time (the last Ma), but Th has remained relatively immobile. High Th/U and²³⁰Th/²³⁴U ratios in surface samples are indicative of rapid leaching of U but little isotopic fractionation, probably within the last 10⁵ a. Apparently unaltered rock, several centimetres distant from the fracture in surface and intermediate- depth samples, has lost appreciable U, but evidence from U-series disequilibrium studies suggests that this process occurred more than one million years ago, perhaps during deuteric or hydrothermal alteration. Core from a fracture at depth in the granite shows little hematite or clay formation and lacks evidence of REE and recent or ancient actinide mobilisation.The U-series results are correlated with the observed concentrations and isotope activity ratios of U in groundwaters sampled from the same or adjacent fractures. Analyses of samples of highly altered rubble recovered from centre portions of fracture zones at the URL show both excesses and deficiencies of²³⁴U and²³⁰Th in neighbouring locations, possibly due to the presence of a redox front whose position is controlled by modern groundwater composition.The implications of these results are discussed for the concept of disposal of nuclear fuel waste at depth in plutonic rock on the Canadian Shield.     

中国大陆科学钻探主孔自然放射性测井及其解释

为了认识江苏东海超高压变质带上地壳岩石自然放射性的垂向分布特征, 榴辉岩退变质程度对放射性元素浓度的影响, 以及放射性产热率对地温梯度的影响, 利用中国大陆科学钻探(CCSD) 主孔100~5000m自然放射性测井(自然伽马和自然伽马能谱) 资料统计了CCSD主孔各类岩石的自然放射性强度和铀、钍、钾元素的浓度, 计算出产热率曲线.自然伽马, 铀、钍、钾浓度和产热率从蛇纹岩到榴辉岩、角闪岩、副片麻岩、正片麻岩依次增大.随着榴辉岩退变质程度的增强, 其铀、钍、钾元素的浓度值逐渐增大.CCSD主孔自然放射性的垂向分布特征主要受岩性控制, 自然放射性随深度增加有增强趋势.产热率与自然伽马测井值之间有很好的线性关系, 在高放射性岩层的上部, 地温梯度会出现较强扰动和低值异常.      

Classification and mineralization potential of the pegmatites of the Eastern Brazilian Pegmatite Province

The potential for Nb, Ta, Li, Sn-mineralization as well as for precious stones for the Eastern Brazilian Pegmatite Province (EBPP) has been evaluated on the basis of 530 K-feldspar and 550 muscovite major and trace element analyses. The EBPP is situated mainly in the State of Minas Gerais, but encompasses also parts of the States of Bahia, Espírito Santo and Rio de Janeiro. The EBPP is the largest pegmatite province of South America. It was divided into the pegmatite districts of Itambé, Araçuaí, Safira, Nova Era, Aimorés and Espera Feliz. This was done to test whether the pegmatites of these districts differ in their mineralization potential and how geotectonic setting influences mineralization potential. The fractionation diagrams such as Cs, Zn, Li, Be, Ba versus K/Rb, Cs versus Ta/(Ta + Nb), and U, Na₂O versus K/Cs for the pegmatite districts of Araçuaí and Safira show the widest range in fractionation. These pegmatite districts are leaders in the production of gem-quality tourmaline, aquamarine, morganite, and contain abundant spodumene, tantalite and columbite. In contrast, the Espera Feliz and Aimorés pegmatite districts are the most primitive districts examined and have a corresponding lack of rare-element mineralization. Literature data indicate that all studied pegmatites are of Brasiliano age, i.e., formed between 600 and 480?Ma. The pegmatites of Transamazonic age (1.9?Ga), found rarely in the study area, are of economic importance in the context of emerald mineralization, but seem to be of less importance for rare metal and other gemstone mineralization.     

Large-ion lithophile element characteristics of an amphibolite facies to granulite facies transition at Gruinard Bay, North-west Scotland

Abstract Lewisian grey gneisses from Gruinard Bay, North-west Scotland retain mineralogical and geochemical evidence for Scourian horn-blende-granulite facies metamorphism, and they may be used to assess current models of elemental depletion at granulite grade. Their 'immobile'major and trace element geochemistry is indistinguishable from that of Lewisian amphibolite and pyroxene-granulite facies counterparts. The K, Rb, Th and U contents of the Gruinard Bay gneisses are depleted relative to amphibolite facies gneisses, but generally the abundances of these elements are above those of comparable pyroxene granulites. U and Th have reached an advanced stage of depletion, but allanite appears to be crucial in maintaining significantly higher U and Th abundances at Gruinard Bay than in pyroxene granulites. K and Rb loss is less extreme, and depends on the stability of the rock-forming minerals: K-feldspar; biotite; and, amphibole. Early removal of K and Rb has resulted in a small rise in K/Rb, but further preferential Rb loss would have been required to generate the characteristically high K/Rb ratios of Lewisian pyroxene granulites.
The residence of U and Th in the accessory minerals of granulite facies gneisses, which are often correlated with the residua of intracrustal partial melting, renders unlikely their extreme incompatibility required by such models. Even if such phases are ignored, high mineral-melt partition coefficients for silicic melts argue against partial fusion as an efficient depletion mechanism. On the other hand, the advanced stage of U and Th depletion reached in Gruinard Bay gneisses, which were still partly hydrous, severely restricts the role played by CO₂-dominated fluids and a hydrous medium is preferred.     

Development of the early continental crust. Part III. Depletion of incompatible elements in the mantle

New analyses and critical re-evaluation of older data permit another estimate of the abundances of some 42 elements in the silicate shells of the Earth, excluding the core.These data and estimations of volcanic rock production lead to a series of estimates of the mass-fractions of depleted and undepleted mantle. Most likely estimates of the latter lie in the range 0.2–0.4. The best estimates are obtained for the most incompatible elements K, Rb, Sr, Ba, Nb, Th, U.The development of the continental crust and the change in tectonic processes over time is consistent with these interpretations.     

The role of industrial archaeology in conservation: The Reşiţa area of the Romanian Carpathians

Industrial archaeology has developed as an important aspect of conservation during the second half of the twentieth century in the Western world and there have been great opportunities in transition countries since 1989 on account of economic restructuring and the importance given to 'niche' tourism. While the core interest lies with machines and industrial buildings, attention is also given to transport systems and the social context, with respect to relations between owners, managers and workers. Moreover, the desirability of maintaining old industrial installations within their traditional landscape settings enables industrial archaeology to make a contribution to sustainable development. This paper considers the prospects for Romania, with particular reference to the Reşiţa area of the Banat Carpathians. The mineral resources of this region gave rise to a metallurgical industry which was established under Habsburg administration in the eighteenth century and continues today. In addition to the principal factories in Anina and Reşiţa, the mining installations, transport systems and power stations contribute to a diverse industrial region in a distinctive physical and cultural setting. The development of the complex is summarised and the opportunities for conservation are evaluated. The tourist infrastructure of the area is also examined with regard to the range of accommodation available. This revised version was published online in July 2006 with corrections to the Cover Date.     

Employment in retailing: A case study of employment in suburban shopping centres

There have been many studies of the retail industry in recent years, and of the impact that retailing has had on the spatial arrangement of urban areas and on consumer behaviour. Little attention has been paid, however, to employment in retailing, which is disturbing in view of its growing importance and its rapidly changing nature and composition. This paper examines the nature of the broad structural changes within the industry, and investigates their spatial consequences through a case study of employment generation within a system of suburban retail centres in Canberra, Australia. It is shown that the evolution of suburban centres, particularly those of a regional variety, has had an important and enriching impact on the suburban labour market. The regional centres are also seen to be the focus of the major structural employment changes currently affecting the retail industry. This has some important implications for urban planning.     

Heat-producing elements in the lunar mantle: Insights from ion microprobe analyses of lunar pyroclastic glasses

We provide new estimates for the abundance of heat-producing elements in the lunar mantle by using SIMS techniques to measure the concentrations of thorium and samarium in lunar pyroclastic glasses. Lunar pyroclastic glasses are utilized in this study because they represent quenched products of near-primary melts from the lunar mantle and as such, they provide compositional information about the mantle itself. Thorium and samarium were measured because: (1) Th is not significantly fractionated from Sm during partial melting of the pyroclastic glass source regions, which are dominated by olivine and pyroxene. Therefore, the Th/Sm ratios that we measure in the pyroclastic glasses reflect the Th/Sm ratio of the pyroclastic glass source regions. (2) Strong correlations between Th, U, and K on the Moon allow us to use measured Th concentrations to estimate the concentrations of U and K in the pyroclastic glasses. (3) Th, Sm, U, and K are radioactive elements and as such, their concentrations can be used to investigate heat production in the lunar mantle.The results from this study show that the lunar mantle is heterogeneous with respect to heat-producing elements and that there is evidence for mixing of a KREEP component into the source regions of some of the pyroclastic glasses. Because the source regions for many of the glasses are deep (?400 km), we propose that a KREEP component was transported to the deep lunar mantle. KREEP enriched sources produce 138% more heat than sources that do not contain KREEP and therefore, could have provided a source of heat for extended periods of nearside basaltic magmatism. Data from this study, in conjunction with models for the fractional crystallization of a lunar magma ocean, are used to show that the average lunar mantle contains 0.15 ppm Th, 0.54 ppm Sm, 0.039 ppm U, and 212 ppm K. This is a greater enrichment in radiogenic elements than some earlier estimates, suggesting a more prolonged impact of radiogenic heat on nearside basaltic volcanism.     

Distribution of radioactive isotopes in rock and ore of Arkhangelskaya pipe from the Arkhangelsk diamond province

The contents of radioactive elements and the uranium isotopic composition of kimberlite in the Arkhangelskaya pipe at the M.V. Lomonosov deposit and of nearby country rocks have been studied. A surplus of ²³⁴U isotope has been established in rocks from the near-pipe space. The high γ = ²³⁴U/²³⁸U ratio is controlled by the geological structure of the near-pipe space. A nonequilibrium uranium halo reaches two pipe diameters in size and can be regarded as a local ore guide for kimberlite discovery. The rocks in the nearpipe space are also characterized by elevated or anomalous U, Th, and K contents with respect to the background.     

镓矿资源需求趋势分析与中国镓产业发展思考

镓是一种伴生矿,主要与铝、锌、锗的矿物伴生,没有独立的矿床,我国金属镓资源储量丰富。作为重要的半导体材料,镓广泛地应用于无线电通讯、光纤通信、汽车雷达、LED照明、太阳能电池等领域,且金属镓所有用途几乎都和当前现代科技发展及低碳经济、绿色能源和环境保护相关。随着镓消费量的不断增长以及镓应用领域的拓展,金属镓的重要性已经被越来越多的国家注意。本文采用部门分析法分别预测镓在砷化镓、LED、薄膜太阳能领域的应用,预测出全球2020年镓金属需求约410~430 t,并对中国镓产业发展面临的问题进行分析,提出增强下游镓产品竞争力、保护镓金属产能的政策建议。