Geomorphological and sedimentary evidence of probable glaciation in the Jizerské hory Mountains, Central Europe

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• 作者：Zbyněk Engel^a ; ^{engel@natur.cuni.cz} ; Marek Kří ; žek^a ; Marek Kasprzak^b ; Andrzej Traczyk^b ; Martin Hložek^a ; Klá ; ra Krbcová ; ^a
• 关键词：Mountainside hollow ; Electrical resistivity tomography ; Sediment morphology ; Quartz grain micromorphology
• 刊名：Geomorphology
• 出版年：2017
• 出版时间：1 March 2017
• 年：2017
• 卷：280
• 期：Complete
• 页码：39-50
• 全文大小：2518 K
• 卷排序：280

文摘

The Jizerské hory Mountains in the Czech Republic have traditionally been considered to be a highland that lay beyond the limits of Quaternary glaciations. Recent work on cirque-like valley heads in the central part of the range has shown that niche glaciers could form during the Quaternary. Here we report geomorphological and sedimentary evidence for a small glacier in the Pytlácká jáma Hollow that represents one of the most-enclosed valley heads within the range. Shape and size characteristics of this landform indicate that the hollow is a glacial cirque at a degraded stage of development. Boulder accumulations at the downslope side of the hollow probably represent a relic of terminal moraines, and the grain size distribution of clasts together with micromorphology of quartz grains from the hollow indicate the glacial environment of a small glacier. This glacier represents the lowermost located such system in central Europe and provides evidence for the presence of niche or small cirque glaciers probably during pre-Weichselian glacial periods. The glaciation limit (1000 m asl) and paleo-ELA (900 m asl) proposed for the Jizerské hory Mountains implies that central European ranges lower than 1100 m asl were probably glaciated during the Quaternary.