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Особенности селеформирования в вулканических регионахстатья
- Автор: Лебедева Е.В.
- Сборник: Селевые потоки: катастрофы, риск, прогноз, защита. Труды 6-й Международной конференции (Душанбе–Хорог, Таджикистан)
- Редакторы: Висхаджиева Карина Сайдовна, Черноморец Сергей Семенович
- Том: 1
- Год издания: 2020
- Место издания: ООО «Промоушн», Душанбе
- Первая страница: 460
- Последняя страница: 469
- Аннотация: Volcanic debris flows - lahars, the formation of which is associated with the displacement of pyroclastic material along the slopes and valleys by melt water and / or precipitation both during and after eruptions - are well studied. However, a detailed analysis of volcanically active regions shows that debris flows can form there under the influence of various other factors. In particular, the formation of dammed water bodies as a result of blocking the valleys with volcanic (pyroclastic and lava flows) and material (debris avalanches, explosive deposits) and the subsequent destruction of dams as a result of erosion, accompanied by a catastrophic descent of lakes, are observed there.Eruptions within or in close proximity to large masses of water in a solid or liquid state lead to catastrophic melting of glaciers, splashing of lakes or the formation of tsunamis in them, which is also inevitably accompanied by debris flows. Volcanic-tectonic events (caldera or fault formation, extrusion growth) occupy a special place. They are leading to fairly rapid changes in the topography of the area, which, in turn, causes the occurrence of new water bodies, the displacement of water masses, and the intensification of erosion with a high probability of subsequent debris flow formation. Seismic shocks accompanying the eruption, although they are rather weak, can cause the destruction of the walls of crater lakes, provoke the formation of rockfalls and landslides, with temporary blocking of river valleys, thereby also creating the prerequisites for debris flows. Most actively, these processes occur in hydrothermal zones, where, under the influence of aggressive thermal waters, bedrock weathering occurs to the state of malleable clays. Concrete examples of debris flow events caused by diverse volcanic activity, accompanying seismic shocks and hydrothermal activity are considered.
- Добавил в систему: Лебедева Екатерина Владимировна