Academic Journal

The 2002 rock/ice avalanche at Kolka/Karmadon, Russian Caucasus: assessment of extraordinary avalanche formation and mobility, and application of QuickBird satellite imagery

التفاصيل البيبلوغرافية
العنوان: The 2002 rock/ice avalanche at Kolka/Karmadon, Russian Caucasus: assessment of extraordinary avalanche formation and mobility, and application of QuickBird satellite imagery
المؤلفون: C. Huggel, S. Zgraggen-Oswald, W. Haeberli, A. Kääb, A. Polkvoj, I. Galushkin, S. G. Evans
المصدر: Natural Hazards and Earth System Sciences, Vol 5, Iss 2, Pp 173-187 (2005)
بيانات النشر: Copernicus Publications, 2005.
سنة النشر: 2005
المجموعة: LCC:Environmental technology. Sanitary engineering
LCC:Geography. Anthropology. Recreation
LCC:Environmental sciences
LCC:Geology
مصطلحات موضوعية: Environmental technology. Sanitary engineering, TD1-1066, Geography. Anthropology. Recreation, Environmental sciences, GE1-350, Geology, QE1-996.5
الوصف: A massive rock/ice avalanche of about 100x106m3 volume took place on the northern slope of the Kazbek massif, North Ossetia, Russian Caucasus, on 20 September 2002. The avalanche started as a slope failure, that almost completely entrained Kolka glacier, traveled down the Genaldon valley for 20km, was stopped at the entrance of the Karmadon gorge, and was finally succeeded by a distal mudflow which continued for another 15km. The event caused the death of ca. 140 people and massive destruction. Several aspects of the event are extraordinary, i.e. the large ice volume involved, the extreme initial acceleration, the high flow velocity, the long travel distance and particularly the erosion of a valley-type glacier, a process not known so far. The analysis of these aspects is essential for process understanding and worldwide glacial hazard assessments. This study is therefore concerned with the analysis of processes and the evaluation of the most likely interpretations. The analysis is based on QuickBird satellite images, field observations, and ice-, flow- and thermo-mechanical considerations. QuickBird is currently the best available satellite sensor in terms of ground resolution (0.6 m) and opens new perspectives for assessment of natural hazards. Evaluation of the potential of QuickBird images for assessment of high-mountain hazards shows the feasibility for detailed avalanche mapping and analysis of flow dynamics, far beyond the capabilities of conventional satellite remote sensing. It is shown that the avalanche was characterized by two different flows. The first one was comparable to a hyperconcentrated flow and was immediately followed by a flow with a much lower concentration of water involving massive volumes of ice. The high mobility of the avalanche is likely related to fluidization effects at the base of the moving ice/debris mass with high pore pressures and a continuous supply of water due to frictional melting of ice. The paper concludes with implications of the Kolka/Karmadon event for worldwide glacial hazard assessments. It is emphasized that situations with large glacierized high-mountain walls with potentially unstable glaciers within impact distance need special attention and monitoring efforts.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1561-8633
1684-9981
Relation: http://www.nat-hazards-earth-syst-sci.net/5/173/2005/nhess-5-173-2005.pdf; https://doaj.org/toc/1561-8633; https://doaj.org/toc/1684-9981
URL الوصول: https://doaj.org/article/cf464a9925ab4c0b9a23d41f3aeaf022
رقم الانضمام: edsdoj.f464a9925ab4c0b9a23d41f3aeaf022
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