Jungquartäre Hangsedimente als Archive der Landschaftsgeschichte in der Colorado Front Range, U.S.A.

作为美国科罗拉多前岭景观历史档案的年轻第四纪斜坡沉积物

基本信息

批准号：
190161295
负责人：
Professor Dr. Jörg Völkel
金额：
--
依托单位：
School of Agriculture and Environment
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2011
资助国家：
德国
起止时间：
2010-12-31 至 2014-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/190161295?language=en
关键词：
Jungquart re Hangsedimente als Archive

项目摘要

The subalpine to montane zones of the Colorado Front Range, U.S.A. are characterized by the abundance of stratified slope deposits exhibiting depths > 1 m and recurring sediment characteristics within the respective strata complexes. Apart from the initial description by Leopold et al. (2008a), they have not been investigated up to now in terms of either their genesis or age. First OSL dating attempts demonstrate the general applicability of the dating method in this context and render last glacial ages ranging between 40 and 12 ka. Across a landscape transect stretching W-E from the subalpine zone east of the Continental Divide (tree line at Niwot Ridge) to the zone of the Foot Hills at the border with the Great Plains (Boulder), 20 representative profiles are investigated with regards to hypsometric differences in stratification, sediment characteristics and morphodynamics. Most notably the montane zone of the Colorado Front Range is characterized by a lack of paleoclimatically interpretable geoarchives due to its semiarid climatic conditions. Additionally the slope sediments provide a basis for discussing the position of the permafrost line during the LGM. Therefore the project contributes a novel approach to the reconstruction of paleoenvironments and paleoclimates across the various altitudinal zones of the Colorado Front Range.

美国科罗拉多州前山脉的亚山坡至山地区域的特征是，在各个地层复合物中表现出深度> 1 m的分层斜坡沉积物的丰富性。除了Leopold等人的最初描述外。（2008a），迄今尚未根据其起源或年龄进行调查。第一个OSL约会尝试证明了在这种情况下约会方法的一般适用性，并使最后的冰川年龄在40至12 ka之间。从大陆鸿沟（Niwot Ridge的树线）以东的亚高山区域（niwot Ridge的树线）到边界上有大平原（Boulder）的步行山带（Boulder）的横向延伸W-E的横向延伸W-E，研究了20个具有代表性的轮廓，以分层特征，沉积物特征和形态学方面的催眠差异。最值得注意的是，科罗拉多州前范围的蒙塔尼区的特征是由于其半干旱的气候条件缺乏古气候的地理。另外，斜率沉积物为讨论LGM期间多年冻土线的位置提供了基础。因此，该项目为在科罗拉多州前范围的各个高度区域重建古环境和古气候的重建提供了一种新颖的方法。