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The paper examines the impact of re-regulation of the British building society industry, between 1986 and 1997. Re-regulation of retail financial markets has split the building society movement between those, mainly large societies, which regard regulation as too restrictive and have decided to become more broadly-based public-limited companies, and the remaining, predominantly medium and smaller-sized building societies, that intend to continue to focus on personal savings and mortgage business. Both sets of companies are pursuing a strategy of consolidation in response to the more competitive environment promoted by regulatory change. The analysis of this restructuring provides a different perspective on the British financial sector, because unlike most of the financial sector, the building society movement is northern-based. Nevertheless, analysis of branch networks suggests that large societies are being attracted to the South East by the higher levels of income and wealth in that area. In contrast, branch closures have been mainly in smaller urban centres, in the north and west of Britain. It seems, however, in the short term at least, that this rationalization is unlikely to be on the scale found in the banking sector. 相似文献
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Summary Many small podiform chromitite deposits occur within two alpine-type serpentinite belts (of uncertain age) in southern NSW. Most of these deposits are enclosed in massive serpentinised chromite-rich dunite which cross-cuts primary layering within the main harzburgite body. In the western belt, the chromitites are all Cr-rich, whereas in the eastern belt there is a spectrum from Cr-rich to highly Al-rich chromitites, all of which have a fairly Complex geographic distribution. All of the chromitites are ophiolitic in character and the chemistry of both the chromitites and discrete chromite grains is reasonably Constant within a deposit, but varies widely between deposits. The REE concentrations are very low and lack any systematic geographic distribution. Most of the hromitites have an opholitic PGE signature, although some exceptions do occur and this is ascribed to localised remobilisation during serpentinisation. PIXE proton probe results show that the chromite grains are enriched, relative to the. serpentine fracture-fill, in Mn, Ni, Zn and Ga and depleted in As and Cu. Inclusions Completely enclosed within the chromite grains include Al-rich chromite, PGE-bearing nickel sulphides, palladian gold, forsteritic olivine, pargasitic amphiboles and a member of the gedrite/anthophyllite group. PGE-bearing fracture-fill phases include millerite, heazlewoodite, polydymite, chalcopyrite, trevorite, native gold, ruthenium, palladium and Ni3Pt(?). Other fracture-fill phases include awaruite, magnetite, pentlandite, lizardite 6T, chrysotile 2M, antigorite, talc, clinochlore IIb, uvarovite garnet, diopside and ferritchromit. The chromitites were derived from a different magma than the peridotite and the present distribution of low Al, intermediate Al and high Al Chromitites reflects the spatial distribution of a progressively fractionating parental magma rather than different magmatic sources. Both the trace element and REE Chemistries of the chromitites yield little insight into the genesis of the chromitite pods and their distribution Could reflect either an inhomogeneous distribution in the parental magma or localised remobilisation during serpentinisation. During serpentinisation, PGE within the chromities and hostrock dunites and harzburgites were released, and precipitated within the crack seal breccia environment of the chromitites. Provided that the inclusions enclosed within the chromite grains formed in the presence of the same fluid as the chromite, this magmatic chromite and olivine forming liquid must have had a minor concentrated volatile-rich component. Subsequent serpentinisation of the chromitites was responsbile for the localised remobilisation of metals, PGE, S and the REE.
With 4 Figures 相似文献
Chemismus und Mineralogie von podiformen Chromitlagerstätten, Süd-NSW, Australien: Ein Schlüssel zu ihrer Entstehung und Entwicklung
Zusammenfassung Zahlreiche kleinere podiforme Chromitlagerstätten treten in zwei alpinotypen Serpinitingürteln unsicherer Altersstellung im südlichen NSW auf. Die meisten dieser Lagerstätten sind an serpentinisierte chromitreiche Dunite, die den primären Lagenbau der Harzburgitkörper durchsetzen, gebunden. Im westlichen Gürtel sind die Chromite Cr-reich, im östlichen reicht das Spektrum von Cr- bis Al-reichen Chromititen mit komplexer geographischer Verbreitung. Alle Chromitite zeigen ophiolitischen Charakter und die Zusammensetzung der Chromitite aber auch einzelner Chromitkörner ist relativ konstant innerhalb einer Lagerstätte. Sie variiert allerdings von Lagerstätte zu Lagerstätte. Die SEE Gehalte sind sehr niedrig. Eine systematische geographische Verteilung ist nicht erkennbar. Die meisten Chromitite zeigen ophiolitische PGE Verteilungsmuster, obwohl es auch Ausnahmen, die lokaler Remobilisation im Zuge der Serpentinisierung zugeschrieben werden müssen, beobachtbar sind. Ergebnisse von PIXE Protonensondenanalysen zeigen, daß die Chromitkörner im Vegleich zu den Serpentinitrißfüllungen an Mn, Ni, Zn und Ga angereichert und an As und Cu angereichert sind. Al-reiche Chromite, PGE-führende Nickelsulfide, Gold mit Palladium, Forsterit und pargasitische Amphibole, sowie Gedrit/Antophyllit sind als Einschlüsse in Chromit nachgewiesen. In PGE-führenden Rissen kommen Millerit, Heazlewoodit, Polydymit, Kupferkies, Trevorit, gedigenes Gold, Ruthenium, Palladium und Ni3Pt(?) vor. Andere Phasen in diesen Rißfüllungen sind Awaruit, Magnetit, Pentlandit, Lizardit 6T, Chrysotil 2M, Antigorit, Talk, Klinochlor IIb, Uvarovit, Diopsid und Ferritchromit.Die Chromitite sind von einem anderen Magma als die Peridotite abzuleiten und die nunmehrige Verteilung von Al-armen bis Al-reichen Chromititen spiegelt die räumliche Verteilung eines fraktionierenden Ausgangsmagmas eher wider als unterschiedliche Magmenquellen. Spuren- und REE-Geochemie erlauben kaum Einblicke in die Genese der Chromititkörper. Ihre unregelmäßige Verteilung könnte entweder auf Inhomogenitäten des Ausgangsmagmas oder auf lokale Remobilisation im Zuge der Serpentinisierung zurückzuführen sein. Während der Serpentinisierung wurden PGEs in den Chromititen und dunitischen und harzburgitischen Nebengesteinen freigesetzt und in den ehromititischen crack-seal Brekzien wiederausgefällt. Unter der Annahme, daß sich die Einschlüsse in den Chromitkörnen in Gegenwart desselben Fluids wie die Chromite selbst gebildet haben, müssen die magmatischen Chromit- und olivinführenden Schmelzen mit einer volatilreichen Komponente koexistiert haben. Nachträgliche Serpentinisierung der Chromitite war für die lokale Remobilisation der Metalle, der PGEs, S und der REE verantwortlich.
With 4 Figures 相似文献
86.
Julienne R. Emry Alison Olcott Marshall Craig P. Marshall 《Geostandards and Geoanalytical Research》2016,40(1):29-47
Raman hyperspectral imaging is becoming a popular technique to analyse geological materials. Autofluorescence can affect the quality of the spectra that comprise hyperspectral data sets. Few studies have addressed potential misinterpretation of Raman images from hyperspectral data sets affected by autofluorescence. Additionally, little work has been done to develop methods for identifying the spatial distribution of spectra affected by autofluorescence. This study illustrates how autofluorescence may lead to misinterpretation of the distribution of materials based on intensity at a point images. A method is proposed utilising signal to axis analysis to create images that identify regions affected by autofluorescence. Post‐processing baseline correction is often used to address autofluorescence, and most software programs utilise a form of partial least squares regression modelling based on a subjective choice of polynomial order. This study shows that an inappropriate choice of polynomial order can introduce error, which may lead to misinterpretation of Raman images. A signal to axis analysis method is proposed to statistically compare seemingly ‘appropriate’ baseline correction trials. Although post‐processing of hyperspectral data sets and creating Raman images seem simple, data quality issues such as autofluorescence must be considered. If baseline correction is deemed necessary, it should be addressed as an experiment involving statistical comparison. 相似文献
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Katherine?CalvinEmail author Marshall?Wise Patrick?Luckow Page?Kyle Leon?Clarke Jae?Edmonds 《Climatic change》2016,136(1):57-68
The magnitude and character of the global resource base of fossil fuels is a key determinant of the evolution of the future global energy system and corresponding fossil fuel carbon emissions. What is less well understood is the potential magnitude of impact of the availability of fossil fuels, due to the interaction with biomass energy, on agriculture, land use, ecosystems and therefore carbon emissions from land-use change. This paper explores these links and implications. We show that if oil resources are limited, then the consequently higher price for liquids induces both the use of coal-to-liquids technology deployment, but also enhanced production of bioenergy crops particularly in a business-as-usual scenario. This in turn implies greater pressure to convert unmanaged ecosystems to produce bioenergy, and higher rates of terrestrial carbon emissions from land use. 相似文献
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Adjustment of Wind Waves to Sudden Changes of Wind Speed 总被引:1,自引:0,他引:1
An experiment was conducted in a small wind-wave facility at the Ocean Engineering Laboratory, California, to address the following question: when the wind speed changes rapidly, how quickly and in what manner do the short wind waves respond? To answer this question we have produced a very rapid change in wind speed between U low (4.6 m s?1) and U high (7.1 m s?1). Water surface elevation and air turbulence were monitored up to a fetch of 5.5 m. The cycle of increasing and decreasing wind speed was repeated 20 times to assure statistical accuracy in the measurement by taking an ensemble mean. In this way, we were able to study in detail the processes by which the young laboratory wind waves adjust to wind speed perturbations. We found that the wind-wave response occurs over two time scales determined by local equilibrium adjustment and fetch adjustment, Δt 1/T = O(10) and Δt 2/T = O(100), respectively, in the current tank. The steady state is characterized by a constant non-dimensional wave height (H/gT 2 or equivalently, the wave steepness for linear gravity waves) depending on wind speed. This equilibrium state was found in our non-steady experiments to apply at all fetches, even during the long transition to steady state, but only after a short initial relaxation Δt 1/T of O(10) following a sudden change in wind speed. The complete transition to the new steady state takes much longer, Δt 2/T of O(100) at the largest fetch, during which time energy propagates over the entire fetch along the rays (dx/dt = c g) and grows under the influence of wind pumping. At the same time, frequency downshifts. Although the current study is limited in scale variations, we believe that the suggestion that the two adjustment time scales are related to local equilibrium adjustment and fetch adjustment is also applicable to the ocean. 相似文献
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