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KARl GARNLS OLL FKEDRIK BERGERSEN 《Boreas: An International Journal of Quaternary Research》1977,6(2):135-147
The morphogenesis of tills below the culmination zones of the Weichsclian inland ice has been studied an an upland area with a relief of 1500 m. The thickness of the tills varies considerably, depending principally on gee-morphology, ice-movement directions, and glaciofluvial drainage during the last deglaciation period. The thickest tills, found in valleys, accumulated in three ways. Glaciofluvial/lacustrine sediments of prcsumed Mid-Weichselian age have been discovered beneath the tills at niorc than 10 localities. The overlying tills are correlated with different phases of ice movement reconstructed on the basis of detailed studies of stt-iae. The till stratigraphy of one locality, Stenseng, is described in detail. Based upon combined analyses of texture, structure, and fabric, four different hasal tills are recognized, each corresponding to a particular ice direction. A characteristic boulder layer represents a change in thc direction of glacial movement. Boulder layers in till are thought to he essential for the development of earth pillars. 相似文献
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KARl GRøSFJELD 《Polar research》1992,11(1):11-19
The age of the uppermost part of the Rurikfjellet Member, Janusfjellet Formation, underlying the Helvetiafjellet Formation, is discussed on the basis of the occurrence of dinoflagellate cysts. Samples collected from thirteen localities in western and central Spitsbergen were examined. Forty-eight dinoflagellate cyst species were recorded during the study, but only a few provide good time resolution. They show that the youngest beds of the Rurikfjellet Member, previously regarded to be of Hauterivian age, belong to the Barremian. The presence of Barremian sediments below the base of the Helvetiafjellet Formation at several widely separated localities constrains the diachronism of the Rurikfjellet Member -Helvetiafjellet Formation transition. 相似文献
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