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Testing Lithogenic Thorium‐232 for Fingerprinting of Slush Flows Debris Sources and Sinks in the Khibini Mountains, Kola Peninsula, North‐Western Russiaтезисы доклада
- Авторы: Гаранкина Е.В., Беляев В.Р., Иванов Максим
- Сборник: I International Conference on Research for Sustainable Development in Mountain Regions: Book of Abstracts
- Тезисы
- Год издания: 2016
- Место издания: Instituto Politecnico de Bragança Braganca, Portugal
- Первая страница: 130
- Последняя страница: 130
- Аннотация: The Khibiny mountains is a developing ski resort at the Kola Peninsula, Northern Russia. At the same time it is an arena of widespread hazardous processes, most dangerous amongst which are slush flows and snow avalanches. Hackman valley located in the southern Khibini is affected by frequent slush flows. This process is similar to debris flows, but most of the oversaturated flow mass is represented by snow and ice, while debris compose about 10%. To evaluate geomorphic effects of these hazardous processes it is important to distinguish both main sediment sources with their relative contribution and zones of debris deposition. Fingerprinting approach has been proved to be useful for determination of sediment sources and sinks in wide variety of geomorphic landscapes. Radionuclides can be used for fingerprinting purposes in cases if their chemical properties determine dominant redistribution in fixed conditions with sediment particles. We attempted to apply the natural lithogenic radionuclide Thorium‐232 (232Th) for slush flows debris fingerprinting. Hackman Valley geological structure is characterized by alternation of plutonic complexes with different content of radioactive isotopes. In addition, radioactive mineral exploration was active in the Hackman basin in 1930s. Later it was closed, but its damps on the valley slope under the mine entrance still represent the potential source of the radioactive material for the main stream and slush flows sediment transport. The mine entrance is located on upper part of the right valley slope in its middle reach. We have attempted to assess the radioactive 232Th transfer from the sediment sources (slope screes, avalanche channel fans and eroded banks) into the main stream channel bed sediment and debris deposition zone. The results show that the fingerprinting approach make it possible to assess sediment sources, debris transport distance and some specifics of slush flows dynamics in the case study basin.
- Добавил в систему: Гаранкина Екатерина Вадимовна