Dr. Jörg Christian Robl

Adress

Dept. Geography and Geology
University of Salzburg
5020 Salzburg
Hellbrunnerstraße 34/III


Phone

+43 ((0)662) 8044 - 5419

E-Mail

joerg.robl@sbg.ac.at


Homepage

www.uni-salzburg.at/geo/robl
www.geodynamics.at

Research Interests

Currently our research is focused on landscape evolutions at different spatial and temporal scales as response on tectonic and climatic forcing. This includes the long term evolution of landscapes towards steady state but also single hazardous events like debris flows or rock falls.

 

Active Orogens

Determination of timing, rates, duration and involved volumes of processes and their feedbacks in active orogens in different spatial and temporal scales. This involves field observations and the numerical description of orogen scale deformation, crustal thickening and uplift, the development of drainage systems accompanied by fluvial erosion and hill-slope instabilities.

Natural Hazards

Exploring the occurrence, return period and run-out distance of natural hazards in alpine domains and their impact on infrastructure. This involves the field observation of landslides, debris flows, snow avalanches, rock falls and floodings with sediment redistribution, the numerical description of these processes, the development of mitigation strategies and the implementation of protecting structures in field.

Project Funded

ELEvATE: Elevated Low Relief LandscapEs in Mountain Belts: Active Tectonics or Glacial REshaping? The Eastern Alps as Natural Laboratory.

 

This project is funded by the Austrian Science Fund (FWF) and the government of Salzburg for a period of three years and will commence in March 2019.

The two advertised PhD positions are filled!

Here you find the abstract of the Research Proposal!

 

 

Recent Study (published 2020)

The destiny of orogen-parallel streams in theEastern Alps: the Salzach–Enns drainage system

 

Trost G., Robl J., Hergarten S., Neubauer S.

Read the entire study!

The evolution of the drainage system in the Eastern Alps is inherently linked to different tectonicstages of the alpine orogeny. Crustal-scale faults imposed eastward-directed orogen-parallel flow on major rivers,whereas late orogenic surface uplift increased topographic gradients between the foreland and range and hencethe vulnerability of such rivers to be captured. This leads to a situation in which major orogen-parallel alpinerivers such as the Salzach River and the Enns River are characterized by elongated east–west-oriented catchmentssouth of the proposed capture points, whereby almost the entire drainage area is located west of the capture point.To determine ...

Recent Study (EPSL in revision)

Glacial erosion promotes high mountains on thin crust

Robl J., Hergarten S. and G. Prasicek

Stay tuned! 

Here we present the first global analysis of the morphology and distribution of more than 16,000 peaks. We spatially correlate peak height and steepness with mean elevation and crustal thickness. Our analysis reveals that the steepness of peaks increases with altitude. Comparing peaks of similar altitude, the steepness of peaks increases towards high latitudes, while the crustal thickness supporting these peaks decreases. This evidences for a progressive crustal thinning with intensity and duration of glacial occupation transforming mountain belts from a fluvial towards a glacial topography. Due to the characteristic glacial landscape geometry with very steep peaks separated by spacious glacial valleys even a relatively thin crust is sufficient to supporting very high peaks.

Recent Study (in prep.)

Impact and sensitivity of parameters in debris flow models

Robl J. and S. Hergarten

Stay tuned! 

Debris flows are globally abundant threats for settlements and infrastructure in mountainous regions. Crucial influencing factors for hazard zone planning and mitigation strategies are based on numerical models that describe granular flow on general topography by solving a depth-averaged form of the Navier Stokes equations in combination with an appropriate flow resistance law. In case of debris flows, the Voellmy rheology is a widely used constitutive law describing the flow resistance.  Parameters of the Vollemy fluid are determined by back analysis from observed events so that modelled events mimic their historical counterparts.

Determined parameters characterizing individual debris flows show a large variability (related to fluid composition and surface roughness). However, there may be several sets of parameters that lead to a similar depositional pattern but cause large differences in flow velocity and momentum along the flow path. Fluid volumes of hazardous debris flows are estimated by analyzing historic events, precipitation time series, hydrographs or empirical relationships that correlate fluid volumes and drainage areas of torrential catchments. Beside uncertainties in the determination of the fluid volume the position and geometry of the initial masses of forthcoming debris flows are in general not well constrained but heavily influence the flow dynamics and the depositional pattern even in the run-out zones. In this study, we systematically explore effects of the aforementioned parameters on run-out distance, inundated area and momentum. Our results  indicate that the spatial position and geometry of the release volume in combination with various parameter sets within a realistic range of parameters characterizing the Voellmy fluid heavily influence momentum, inundated areas and run-out distances. Even worse, different parameter sets lead to very similar depositional pattern but may differ in momentum along the flow path by more than one order of magnitude and beyond.

 

Teaching

 




There is no modern academic teaching without research!  Therefore, fundamentals and new scientific findings are presented in the following lessons:

Bachelor Level

  • Introduction to the Basics of Geology
  • Introduction to General and Applied Geology
  • Geographic Information Systems for Geologists
  • Introduction to Numerical Modeling in Geology
  • Excursion: Eastern Alps
  • Tectonic Geomorphology

Master Level

  • Remote Sensing for Geologists
  • Applied Numerical Methods in Geology
  • Geodynamics
  • Natural hazards and geotechnical solutions

PhD Level

  • Data and Figures

Teacher Training  Biology and environmental studies

  • Bioplanet Earth
  • Biology as a science of life (lecture series)

 

 

 

Until now all lessons are held in German and you will find further informations here

 

Latest Publications

Trost, G., Robl, J., Hergarten, S., Neubauer, F., 2020. The destiny of orogen-parallel streams in the Eastern Alps: the Salzach–Enns drainage system. Earth Surf. Dynam. 8, 69-85.

Trost, G., J. Robl, S. Hilberg, C. Hauzenberger, R. Schmidt, and W. Goessler, 2018. Chemical denudation rates of a small torrential catchment in the Northern Calcareous Alps, Austrian Journal of Earth Sciences, 111(1), 1-14.

Prasicek, G., F. Herman, J. Robl, and J. Braun, 2018. Glacial Steady State Topography Controlled by the Coupled Influence of Tectonics and Climate, Journal of Geophysical Research: Earth Surface, 0(0), doi:10.1029/2017JF004559.

Baumann, S., J. Robl, G. Prasicek, B. Salcher, and M. Keil, 2018. The effects of lithology and base level on topography in the northern alpine foreland, Geomorphology, 313, 13-26, doi:https://doi.org/10.1016/j.geomorph.2018.04.006.

Robl, J., S. Hergarten, and G. Prasicek, (2017). The topographic state of fluvially conditioned mountain ranges, Earth-Science Reviews, https://doi.org/10.1016/j.earscirev.2017.03.007

Robl, J., Heberer, B., Prasicek, G., Neubauer, F., Hergarten, S., 2017. The topography of a continental indenter: The interplay between crustal deformation, erosion, and base level changes in the eastern Southern Alps. J Geophys Res Earth Surf 122, 310-334.

Hergarten, S., Robl, J., Stüwe, K., 2016. Tectonic geomorphology at small catchment sizes – extensions of the stream-power approach and the χ method. Earth Surface Dynamics 4, 1-9.

Full List of Publications

More publications are in the pipeline ...