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121.
Julian Holloway 《Geoforum》2000,31(4)
This paper is concerned with the production and reproduction of different institutional geographies of the New Age movement. Instead of taking institutional geographies to be given and fixed co-ordinates in the social field, the paper seeks to understand how they are relational outcomes and effects that require constant upkeep. After characterising the New Age movement, in terms of its central cosmology and visions of transformation, the paper takes an actor-network theory (ANT) approach to the understanding of institutional geographies. Through analysing how New Age knowledges and practices travel through time and space, and utilising ANT’s concept of ‘centres of translation’, institutional geographies are taken to be active space-times that are both enrolled into New Age teachers and practitioners programs of action, and space-times that actively enrol teachers and practitioners. It is argued that the intertwining of different engineered actor-networks in and through these space-times maintains the New Age movement itself and thus examining institutional geographies can tell of the movement’s shape or topology. A controversy over the work of David Icke is explored to reveal how institutional geographies are sites for regulation of what counts as New Age knowledge. Finally, this paper seeks, partially at least, to assess in terms of the ANT approach taken, the visions of transformation propounded by the New Age movement. 相似文献
122.
Palaeoenvironmental records in Holocene Spanish tufas: a stable isotope approach in search of reliable climatic archives 总被引:3,自引:0,他引:3
Tufa deposits are potential terrestrial archives of palaeoenvironmental and palaeoclimatic information. This study assesses the potential of stable isotopic archives from two closely juxtaposed Holocene tufa sites in SE Spain. The Ruidera site contains deep‐water lacustrine micrites and tufas, whereas the nearby Alcaraz site represents a shallow barrage tufa. Understanding site characteristics is critical to interpreting the stable isotopic variations. These Holocene lacustrine micrites have isotopic compositions consistent with modern European lake shore microbial carbonates, where the isotopic chemistry is strongly influenced by hydrological and residence time effects. All the lacustrine micrite δ13C values were influenced by microenvironmental microbial effects to some degree. Because of these effects, stable isotope data from lacustrine microbial micrites and tufas will not normally yield precise information on the isotopic composition of palaeoprecipitation, temperature or vegetation composition of an area. In contrast, Holocene tufas that formed in shallow, fast‐flowing riverine settings may contain valuable palaeoclimatic archives. The tufa deposits must be largely autochthonous, as at Alcaraz, where in situ reed stem encrustations are present. Records of relative change in air temperature and changes in the source of airmasses are potentially resolvable in the δ18O data. These interpretations can be verified by other independent climatic data where chronology is constrained. Variations in riverine tufa δ13C values probably record changes in local vegetation and/or soil respiration. Covariation between δ18O and δ13C values may be intrinsically linked to climatic factors such as aridity. Tentative palaeoclimatic interpretations for the middle Holocene at Alcaraz based on the isotope data suggest warming (or increasing influence of Mediterranean‐sourced precipitation) between approximately 5000–3000 radiocarbon years BP, accompanied by increased aridity. These interpretations are consistent with the sparse independent palaeoclimatic data and climate modelling results for the Holocene of SE Spain. This study supports the growing evidence that well‐chosen tufa sites could yield valuable palaeoclimatic information. 相似文献
123.
Sergey V. Marchenko Gregor Rauw Eleonora A. Antokhina Igor I. Antokhin Dominique Ballereau Jacques Chauville Michael F. Corcoran Rafael Costero Juan Echevarria Thomas Eversberg Ken G. Gayley Gloria Koenigsberger Anatoly S. Miroshnichenko Anthony F. J. Moffat Nidia I. Morrell Nancy D. Morrison Christopher L. Mulliss Julian M. Pittard Ian R. Stevens Jean-Marie Vreux Jean Zorec 《Monthly notices of the Royal Astronomical Society》2000,317(2):333-342
With the objective of investigating the windwind collision phenomenon and supporting contemporaneous X-ray observations, we have organized a large-scale, coordinated optical monitoring campaign of the massive, highly eccentric O9 III+B1 III binary Iota Orionis. Successfully separating the spectra of the components, we refine the orbital elements and confirm the rapid apsidal motion in the system. We also see strong interaction between the components during periastron passage and detect phase-locked variability in the spectrum of the secondary star. However, we find no unambiguous signs of the bow shock crashing on the surface of the secondary, despite the predictions of hydrodynamic simulations. Combining all available photometric data, we find rapid, phase-locked variations and model them numerically, thus restricting the orbital inclination to 50° i 70°. 相似文献
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125.
Sedimentary indications and absolute chronology of Holocene relative sea‐level changes retrieved from coastal lagoon deposits on Samsø, Denmark
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Lasse Sander Mikkel Fruergaard Julian Koch Peter N. Johannessen Morten Pejrup 《Boreas: An International Journal of Quaternary Research》2015,44(4):706-720
Coastal lagoons are a typical feature of the landscape in central Denmark. The lagoons formed when basins within the inherited glacial topography were flooded by the mid‐Holocene sea‐level rise. The transgression initiated coastal geomorphological processes and prompted marine sedimentation in the inundated areas. Despite their common occurrence and wide distribution in the area, coastal lagoons and their deposits have rarely been studied as sedimentary archives. The absolute chronology established for the basal marine deposits in sediment cores retrieved from coastal lagoons on the island of Samsø, southern Kattegat Sea, central Denmark, is evidence of a nearly synchronous onset of marine sedimentation at different elevations. This is interpreted as a new indication of a period of very rapid relative sea‐level (RSL) rise between 7.6 and 7.2 ka BP. Following a period of RSL highstand, a marked facies change in the deposits from an inactive lagoon yields consistent ages of around 4.1 ka BP and may be an indication of a marked RSL fall. This study illustrates the potential of coastal lagoons as sedimentary archives for the reconstruction of RSL in SW Scandinavia and in similar coastal environments elsewhere. 相似文献
126.
Chemical zoning, recorded by grain growth during metamorphism, is a key source of information about P–T–t paths. Interpretation of these data must be carried out using appropriate models and recognizing their inherent assumptions. To assist with defining how zoned minerals form, a set of geometric criteria for three types of chemical zoning developed in minerals (diffusion, growth and grain recycling) is outlined. Re‐equilibration of minerals by lattice diffusion causes zoning if the re‐equilibration is incomplete. Growth of porphyroblasts is commonly considered in pelites, but in metagranitoids, large monophase domains undergo coarsening by recycling of material from one grain to another as grain boundaries migrate driven by surface energy. This type of grain size increase is termed here ‘grain recycling’. Zoning developed during grain recycling due to equilibration of the recycled material with grain‐boundary chemistry is termed ‘grain‐recycling zoning’. Furthermore, short lattice diffusion lengths relative to grain sizes cause metamorphic fractionation because material in the grain cores is not in communication thermodynamically with the rest of the rock. A new model is derived for this sort of grain size increase coupled with metamorphic reactions using Theriak–Domino. An example is given of plagioclase undergoing an increase in anorthite content as epidote breaks down during amphibolite facies metamorphism of a metagranitoid. Agreement between naturally occurring zoning profiles and those derived from modelled P–T–t paths shows that this model can be used to extract metamorphic conditions from rocks which are not accessible using conventional thermobarometry. 相似文献
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Julian J. C. Dawson Doerthe Tetzlaff Mark Speed Markus Hrachowitz Chris Soulsby 《水文研究》2011,25(10):1647-1658
Spatial and temporal variability of hydrological responses affecting surface water dissolved organic carbon (DOC) concentrations are important for determining upscaling patterns of DOC export within larger catchments. Annual and intra‐annual variations in DOC concentrations and fluxes were assessed over 2 years at 12 sites (3·40–1837 km2) within the River Dee basin in NE Scotland. Mean annual DOC fluxes, primarily correlated with catchment soil coverage, ranged from 3·41 to 9·48 g m?2 yr?1. Periods of seasonal (summer–autumn and winter–spring) DOC concentrations (production) were delineated and related to discharge. Although antecedent temperature mainly determined the timing of switchover between periods of high DOC in the summer‐autumn and low DOC in winter‐spring, inter‐annual variability of export within the same season was largely dependent on its associated water flux. DOC fluxes ranged from 1·39 to 4·80 g m?2 season?1 during summer–autumn and 1·43 to 4·15 g m?2 season?1 in winter–spring.Relationships between DOC areal fluxes and catchment scale indicated that mainstem fluxes reflect the averaging of highly heterogeneous inputs from contrasting headwater catchments, leading to convergent DOC fluxes at catchment sizes of ca 100 km2. However, during summer–autumn periods, in contrast to winter–spring, longitudinal mainstem DOC fluxes continue to decrease, most likely because of increasing biological processes. This highlights the importance of considering seasonal as well as annual changes in DOC fluxes with catchment scale. This study increases our understanding of the temporal variability of DOC upscaling patterns reflecting cumulative changes across different catchment scales and aids modelling of carbon budgets at different stages of riverine systems. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献