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131.
In general terms the form of the Bride Moraine, its internal structure, and part of its stratigraphy result from a minor ice-sheet readvance during a late stage of the Devensian deglaciation of the Irish Sea basin. Four major structural styles are identified and are related to four structural zones that run parallel to the crest of the ice-thrust ridge. The structures result from the development of differential permafrost in a sequence of highly contrasting lithologies and the consequent generation of high pore-water pressures during ice-marginal loading. This caused mobilisation of water-saturated clays in the sequence and the development of large-scale diapiric structure in the core of the moraine and low-angles overthrust faulting on the flanks.  相似文献   
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The rain shadow regions requisite a comprehensive watershed development and management plan for sustainable water resources management. The Pambar River Basin (PRB) lies on the rain shadow region of the southern Western Ghats, India, where climate showed marked intra-basin variation. A morphometric analysis was done to evaluate the drainage characteristics of PRB using topographical maps and digital elevation data. PRB was divided into eighteen 4th order basins (SB1-SB18), distributed along various climatic...  相似文献   
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Abstract

Reservoirs in the southern Pennines have been investigated to determine their potential for reconstructing a history of atmospheric pollution. A selection procedure has been used to identify sites with the best chance of obtaining a usable sedimentary record prior to sample collection. Five reservoirs were selected for core collection and sediment analysis using magnetic susceptibility (χlf), particle size, spheroidal carbonaceous particle (SCP) analysis and radiometric dating. Analysis reveals that largely undisturbed sedimentary records exist in the deepest zones of these reservoirs, thus reservoir sediments represent a valuable resource for investigating pollution histories in the southern Pennines.  相似文献   
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本文首先指出经典粘性理论应适用于扇形边界低速风,接着论证了常用太阳风粘性数学表式的不正确性,导出了螺旋磁场中径向球对称强磁化等离子体流动的各种经典粘性表式,并证明了这些公式的合理性;最后讨论了常用太阳风经典粘性表式出错原因,估计了具有正确粘性公式的扇形边界低速太阳风粘性模式应有的结果。  相似文献   
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Bracketing ages on marine—freshwater transitions in isolation basins extending from sea level to 100 m elevation on Lasqueti Island, and data from shallow marine cores and outcrops on eastern Vancouver Island, constrain late Pleistocene and Holocene sea-level change in the central Strait of Georgia. Relative sea level fell from 150 m elevation to about —15 m from 14000 cal. yr BP to 11 500 cal. yr BP. Basins at higher elevations exhibit abrupt changes in diatom assemblages at the marine-freshwater transition. At lower elevations an intervening brackish phase suggests slower rates of uplift. Relative sea level rose to about +1 m about 9000 cal. yr BP to 8500 cal. yr BP, and then slowly fell to the modern datum. The mean rate of glacio-isostatic rebound in the first millennium after deglaciation was about 0.11 in a -1, similar to the peak rate at the centres of the former Laurentide and Fennoscandian ice complexes. The latter feature smooth, exponential-style declines in sea level up to the present day, whereas in the study area the uplift rate dropped to less than one-tenth of its initial value in only about 2500 years. Slower, more deeply seated isostatic recovery generated residual uplift rates of <0.01 m a-1 in the early Holocene after the late-Pleistocene wasting of the Cordilleran ice sheet.  相似文献   
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