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Prof. Dr. K. Brunnacker 《International Journal of Earth Sciences》1977,66(1):755-770
With regards to exogenic proceedings the postglacial time was characterized till now as a geologically stable time, and by this as “the geological present time”. This view may be correct if, e. g., the pedogenesis is considered with continuous processes, but only apparently. But there are differences which are explicable genetically only partly up to the presence, if in Middle Europe holocene rock bildings are considered with, as cave sediments, calc-tufa, peat layers, fluviatile sediments, and others. Finally the man as a further modifying factor is added to, since about the last 5.000 years. Since about the last 20 years a more extensive data material was gained by working for the fluviatile proceedings in the holocene. Therefore at the Lower Rhine, but also at the Danube (“Eisernes Tor”) and on the border of the Alps there is perceptible a trend in diminuation of fluviatile effectivness in approach to the present time. Phases of activities with an interval of about 1.000 years, at least in the youngest holocene, are settled on this principal process. By this, parts of the valley soil are reworked and deposited again downwards the valley. The reason for these proceedings, trends and the shorter activities is unknown, although there are first reference points for connections with oscillations of the glaciers in the Alps and of the sea level in the North Sea. Apparently slight climatic impulses in the border zone of oceanic and continental climate, which are not even perceptible on the vegetation history, might be the reason, at least partly. Next to that it is thinkable that continuously proceeding evolutions can lead to abrupt alterations at swell value. Beyond it, the quantitative effects of human activities are largely unknown. A geoscientific research, oriented into the future, only can come to results reach in meaning if it is able to value the factor of time, and by this the youngest of all earth history. 相似文献
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