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111.
This article examines the geography of pisco, a South American brandy claimed as the national drink of both Peru and Chile. The historic tension between these two nations—based notably on the nineteenth‐century War of the Pacific—is used as a backdrop to understanding the cultural and political contestation over the “ownership” of this beverage. Although both countries see exportation of pisco as a means of agricultural development, much of the animosity of this trade dispute is couched in cultural and historical terms. International trade policies, including the use of geographical indications (labels of geographical origin) for the purposes of trademarking, and the physical geography that makes pisco production possible are discussed. 相似文献
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WILLIAM C. MAHANEY WOLFGANG ANDRES 《Boreas: An International Journal of Quaternary Research》1991,20(3):231-239
Detailed mineralogical analysis of the fine and very fine sand fractions (63–250) in the Dreihausen Loess Sequence shows the presence of numerous glacially crushed grains, including a significant amout of quartz. Previous theories regarding the origin of loesses in central Germany held that all sediments were derived locally, following short-distance transport from nearby sandstone outcrops. New data presented here show that many quartz and feldspar grains were glacially crushed, weathered, crushed again, transported, and emplaced by aeolian processes at Dreihausen. Crushing features observed are compatible with transport in both continental and alpine glaciers; some clasts show the effects of abrasion by both water and ice transport, while others are partly rounded presumably by fluvial and/or aeolian processes. Stronger palewind systems during the Pleistocene presumably contributed to the transport and emplacement of glacial grains from ice centers in both the Alps and the Baltic areas, and also possibly from the Rhine Basin. 相似文献
116.
WILLIAM S.RAYENS 《地理学报(英文版)》1990,(2)
Some well-established ideas from classical covariance stabilization and shrinkage estimation are extendedto the context of physical mixtures through the use of a model developed by Burdick and Rayens.A cross-validation technique is proposed and associated computational issues are addressed.The methodology isevaluated in the context of real polychlorinated biphenyl data. 相似文献
117.
Quantitative relationships between numbers of fluvial cycles, bulk lithological composition and net subsidence in a Scottish Namurian basin 总被引:1,自引:0,他引:1
This detailed quantitative basin analysis of fluvial deposits in a subsiding Namurian structural basin is aimed at discovering underlying statistical relationships between numbers of fluvial cycles, bulk lithological composition and net subsidence which could be used as a background to future sophisticated computer simulation experiments and would also facilitate comparison with other ancient basins. The succession studied lies between two widespread marine bands, one of Arnsbergian (E2) and one of Kinderscoutian (R1) age, and is dominated by upward-fining cycles: 94% of the semi-cycles containing sand, here termed grain-size cycles, are upward-fining and the ratio of fine members (mudstone+siltstone) to coarse members ranges from 0·23 to 5·0. Trend-surface analysis reveals basement structures, which influenced sedimentation, including a Caledonoid graben. Correlation coefficient values and results of principal component analysis demonstrate that the numbers of rooty horizons and grain-size cycles, together with the total thicknesses of sandstone and of mudstone+siltstone, all tend significantly towards a linear relationship with the total thickness of strata and hence net subsidence. The average thickness of grain-size cycles tends towards an inverse linear relationship with net subsidence. This probably reflects the presence of stacked, relatively thin, channel-fills within persistent channel belts. These belts tend to be localized in the areas of greatest subsidence within the basin and follow courses basically similar to channels already discovered in the underlying deltaic sediments. The highest concentrations of mudstone+siltstone tend to lie on the flanks of the basin, but high local sand concentrations found at points on the margin where channels entered the basin from the NW and NE and left to the SW, effectively disrupt any significant relationship between net subsidence and the proportion of sand. Coal has been selectively preserved on the flanks of the basin and the number of rooty horizons is greatest in an area of low subsidence which lay somewhat remote from the main channel belts. 相似文献
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DUNCAN M. FitzGERALD WILLIAM J. CLEARY JOAO THADEU
De MENEZES ANTONIO H. da F. KLEIN 《Sedimentology》2013,60(2):469-502
Clastic, depositional strandplain systems have the potential to record changes in the primary drivers of coastal evolution: climate, sea‐level, and the frequency of major meteorological and oceanographic events. This study seeks to use one such record from a southern Brazilian strandplain to highlight the potentially‐complex nature of coastal sedimentological response to small changes in these drivers. Following a 2 to 4 m highstand at ca 5·8 ka in southern Brazil, falling sea‐level reworked shelf sediment onshore, forcing coastal progradation, smoothing the irregular coastline and forming the 5 km wide Pinheira Strandplain, composed of ca 500 successive beach and dune ridges. Sediment cores, grab samples and >11 km of ground‐penetrating radar profiles reveal that the strandplain sequence is composed of well‐sorted, fine to very‐fine quartz sand. Since the mid‐Holocene highstand, the shoreline prograded at a rate of ca 1 to 2 m yr?1 through the deposition of a 4 to 6 m thick shoreface unit; a 1 to 3 m thick foreshore unit containing ubiquitous ridge and runnel facies; and an uppermost beach and foredune unit. However, the discovery of a linear, 100 m wide barrier ridge with associated washover units, a 3 to 4 m deep lagoon and 250 m wide tidal inlet within the strandplain sequence reveals a period of shoreline transgression at 3·3 to 2·8 ka during the otherwise regressive developmental history of the plain. The protected nature of Pinheira largely buffered it from changes in precipitation patterns, wave energy and fluvial sediment supply during the time of its formation. However, multiple lines of evidence indicate that a change in the rate of relative sea‐level fall, probably due to either steric or ice‐volume effects, may have affected this coastline. Thus, whereas these other potential drivers cannot be fully discounted, this study provides insights into the complexity of decadal‐scale to millennial‐scale coastal response to likely variability in sea‐level change rates. 相似文献
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WILLIAM R. GORDON JR NADER M. SOUBRA 《International journal of geographical information science》2013,27(4):267-278
Abstract Practitioners and academics from many fields of study are currently facing numerous issues involving the diffusion of technologies from geographical information systems within their respective professions. This paper has two aims. The first is to report the partial results of a postal survey of selected municipal planning departments in the U.S.A. In measuring trends related to the adoption of computer and geographical information system technologies, the survey focuses on the availability of trained geographical information system and computer literate staff and on alternative means of training existing staff, as well as on the adequacy of collegiate education. The presentation of survey results is used to establish a framework for the principal discussion of this paper. The second part examines the relationship between planning and education in geographical information systems. Parallels within other disciplines and professions are derived. Curricula and training considerations within academic programmes and professional practice are suggested. 相似文献