Open AccessSedimentological characteristics of debris flow Deposits within ice−cored moraine of Ebbabreen, central Spitsbergen
Author(s) -
Krzysztof Pleskot
Publication year - 2015
Publication title -
polish polar research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.421
H-Index - 32
eISSN - 2081-8262
pISSN - 0138-0338
DOI - 10.1515/popore-2015-0006
Subject(s) - moraine , debris flow , geology , debris , meltwater , deposition (geology) , geomorphology , hyperconcentrated flow , sediment , glacier , sedimentary rock , lithology , sedimentology , mudflow , geochemistry , sediment transport , bed load , oceanography
The Ebbabreen ice−cored moraine area is covered with a sediment layer of up to 2.5 m thick, which mostly consists of massive diamicton. Due to undercutting by lateral streams, debris flow processes have been induced in marginal parts of this moraine. It was recognized that the sedimentology of deposits within the deposition area of debris flows is the effect of: (1) the origin of the sediments, (2) the nature of the debris flow, and (3) post−debris flow reworking. Analysis of debris flow deposits in microscale (thin sections) suggests a common mixing during flow, even though a small amount of parent material kept its original structure. The mixing of sediments during flow leads to them having similar sedimentary characteristics across the deposition area regardless of local conditions (i.e. slope angle, water content, parent material lithology). After the deposition of sediments that were transported by the debris flow, they were then reworked by a further redeposition process, primarily related to meltwater stream action