Projects per year
Abstract
In mountain landscapes, landslides often block river courses. Although
landslides are well-known threats, the risks imposed by landslide dams
are sometimes neglected. The impeding of a river can lead to the
submergence of parts of the upstream valley and a failure of the dam can
flood downstream terrain in a catastrophic event.Our aim is two-fold: we
are interested in creating a landslide dam susceptibility map relying on
modelled landslides and resulting damming of valleys and formation of
lakes, and in studying the relation between the occurrence of landslide
dams and lithology.Landslide susceptibility maps are a common tool for
natural hazard mitigation, but landslide dam susceptibility maps are
rarely produced. Several simple indices (Blockage Index, Backstow Index)
have been developed to predict the obstruction capacity and stability of
landslides on a river from landslide and catchment characteristics
(landslide volume, catchment area, dam height etc.). However, those
methods were applied on observed landslides, and did not consider
landslide susceptibility. Here, we created a first modelling-based
landslide dam susceptibility map and compared it to the results provided
by the indices.Although the relation between lithology and landsliding
has been thoroughly studied, no connection with dam formation has been
highlighted so far. Lithology has an impact on various characteristics
of the landslide, including its volume, and also influences valley
geometry. We investigated if some alpine lithological units are more
prone to landslide dam formation than others.In our modelling approach
we used a 10 m DEM of the Austrian Alps and stochastically triggered
landslides based on slope thresholds. We then simulated the runout of
the landslides using a fluid flow solver. For each landslide deposit we
computed the maximum dammed volume by filling the landslide-dammed DEM,
and compared those volumes to the lithology. We also tested the
different theoretical geomorphological indices to predict the impounding
of the river and compared them to the actual results provided by our
method.
Original language | English |
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DOIs | |
Publication status | Published - Mar 2020 |
Event | EGU2020: Sharing Geoscience Online - Duration: 4 May 2020 → 8 May 2020 |
Online-Conference
Online-Conference | EGU2020: Sharing Geoscience Online |
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Period | 4/05/20 → 8/05/20 |
Fields of Science and Technology Classification 2012
- 105 Geosciences
- 211 Other Technical Sciences
Projects
- 2 Finished
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RiCoLa II: Detektion und Analyse von massenbewegungsinduzierten Flusslaufänderungen und Seebildungen
Hölbling, D. W. (Principal Investigator), Friedl, B. (Co-Investigator), Abad Crespo, L. C. (Co-Investigator) & Dabiri, Z. (Co-Investigator)
1/08/17 → 30/06/21
Project: Research
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RiCoLa: Detektion und Analyse von massenbewegungsinduzierten Flusslaufänderungen und Seebildungen
Prasicek, G. (Principal Investigator) & Hölbling, D. W. (Co-Investigator)
1/08/17 → 30/06/21
Project: Research