Impacts of Landslide Dams on Mountain Valley Morphology

The role of landslides in the evolution of a small mountain river valley (Polish Carpathians)

“…12). The effects of such an event are observed below and above the contact zone of the landslide system and the river (Costa and Schuster;1988;Clague and Evans;1994;Korup, 2005;Schuster, 2006;Hermanns et al 2009;Kuo et al, 2011;Cebulski, 2014Cebulski, , 2016Kumar et al, 2019;Wu et al, 2019). Landslide dams most often occur in tectonically active areas.…”

“…The occurrence of landslides and river coupling leads to the transformation of the longitudinal profile of the river. The longitudinal profile can be observed to consist of large steps, which indicate increased accumulation reducing the capacity of the river channel above the contact section, and increased erosion below (Schuster, 2006;Korup et al, 2010) (Fig. 12).…”

“…As a result, lateral erosion activity increases, which leads to the widening and deepening of the valley floor (Margielewski, 2008). Particularly large changes within the river channel occur during the formation of landslide dams (Costa and Schuster, 1988;Clague and Evans, 1994;Schuster 2006;Hermanns et al, 2009;Kuo et al, 2011;Cebulski 2014Cebulski , 2016Wu et al, 2019;Kumar et al, 2019). According to Costa and Schuster (1988) the most endangered areas are valleys with a narrow floor due to the small area receiving displaced colluvial material.…”

“…The gradient of valley hillslopes also increases the chance of the formation of landslide dams given the increased rate of landslide movement, which allows the stream to be blocked before the material is eroded and removed by the river. According to Schuster (2006) and Korup et al, (2010) landslide dams have a significant impact on the morphology of mountain valleys, changing them both up and down the river from the landslide dam. The effect of this is the formation of often temporary or permanent lakes, accumulation of sediment in front of dams, changes in river channel patterns, and secondary activity of landslides.…”

Impact of massive deep-seated rock slope failures on mountain valley morphology in the northern Cottian Alps (NW Italy)

“…imposing a marked change in the valley-slope profiles due to sagging and toe bulging (Hewitt, Clague, & Orwin, 2008) that, in turn, induce secondary slope instabilities; . causing valley obstructions (Evans et al, 2006;Schuster, 2006) and controlling the downstream transport of sediments (Fort et al, 2009;Korup, Strom, & Weidinger, 2006), sometimes resulting in complete stream blockage and the development of lakes that act as sedimentary traps; . influencing the drainage network and changing the flow paths and the hydrogeochemical characteristics of groundwater due to the dilatancy of the involved rocks (Binet, Guglielmi, Bertrand, & Mudry, 2007;Bogaard et al, 2007;Madritsch & Millen, 2007).…”