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Gewählte Master / Diploma Thesis:

Fabian Markus Arminger (2021): GIS-basierte Untersuchung des geologischen und geomorphometrischen Einflusses auf die Murgangaktivität im Pitztal.
Master / Diploma Thesis - Institut für Alpine Naturgefahren (IAN), BOKU-Universität für Bodenkultur, pp 101. UB BOKU obvsg FullText

Data Source: ZID Abstracts
Abstract:
Debris flows endanger human lives and facilities in the alpine regions. Therefore, understanding the influence of various factors on debris flow occurrence is important. In the present study, the influence of geological and geomorphometric characteristics on debris-flow activity was investigated for 23 catchments within the Pitztal-valley (Tyrol). The basis for this is a GIS-based mapping of all bedrock and unconsolidated rock areas using high-resolution remote sensing data and geological maps. The derived geological parameters describe the presence of bedrocks in the catchment depending on their weathering characteristics as well as the extent of sediment contributing areas together with the fraction of unconsolidated sediment. Regarding the morphometric characteristics, the parameters Average Slope, Melton Ratio, Relief Ratio as well as the length of the channel susceptible to debris flows were determined. Finally, statistical correlation analyses were used to test the relationships between the derived parameters and event frequency for significance. Event frequency was defined as the number of events per catchment since 1950. Additionally, morphometric characteristics of the alluvial fans were used as indicators for debris-flow activity. While there were no significant correlations with the event data, fan characteristics indicating debris-flow activity in the past are positively correlated with the Melton Ratio and negatively correlated with the channel length susceptible to debris flows. Additionally, a distinct decrease in relief energy of the fans can be observed with increasing percentage of bedrock that is more susceptible to weathering. This may be also connected to variations of flow and deposition behaviour of the different types of weathered sediment. Finally, with increasing fraction of sediment contributing area in the catchment, debris-flow activity tends to increase.

Beurteilende*r: Kaitna Roland
1.Mitwirkender: Zangerl Christian
2.Mitwirkender: Aigner Philipp

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