NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-13-3313-2013 Airborne geophysical mapping as an innovative methodology for landslide investigation: evaluation of results from the Gschliefgraben landslide, Austria Supper R. 1 Baroň I. 1 Ottowitz D. 1 Motschka K. 1 Gruber S. 1 Winkler E. 1 Jochum B. 1 Römer A. 1 Geologische Bundesanstalt, Neulinggasse 38, 1030 Wien, Austria 17 12 2013 13 12 3313 3328 Copyright: © 2013 R. Supper et al. 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/articles/13/3313/2013/nhess-13-3313-2013.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/13/3313/2013/nhess-13-3313-2013.pdf

In September 2009, a complex airborne geophysical survey was performed in the large landslide affected area of the Gschliefgraben valley, Upper Austria, in order to evaluate the applicability of this method for landslide detection and mapping. An evaluation of the results, including different remote-sensing and ground-based methods, proved that airborne geophysics, especially the airborne electromagnetic method, has a high potential for landslide investigation. This is due to its sensitivity to fluid and clay content and porosity, which are parameters showing characteristic values in landslide prone structures. Resistivity distributions in different depth levels as well as depth slices along selected profiles are presented and compared with ground geoelectrical profiles for the test area of Gschliefgraben. <br><br> Further interesting results can be derived from the radiometric survey, whereas the naturally occurring radioisotopes <sup>40</sup>K and <sup>232</sup>Th, as well as the man-made nuclide <sup>137</sup>Cs have been considered. While the content of potassium and thorium in the shallow subsurface layer is expressively related to the lithological composition, the distribution of caesium is mainly determined by mass wasting processes.

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