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Zur Person:
Studium der Technischen Physik (TU Graz)
Dissertation und Habilitation (MUL)
derzeit: ao.Prof. Lehrstuhl für Geophysik (MUL)
Landslide forecasting
The possibilities of landslide forecasting by geophysical measurements, especially
by the geoelectric method have been investigated.
actual approach is focused on the detection of the
first mentioned longer term steady changes in the
subsurface properties. Geophysical techniques are
very good suited to fulfil this task.
Repeated geoelectric measurements had been
applied to detect changes in the subsurface,
prior to the landslide. These data (figure above)
showed, verified by the later on landslide event,
already changes in the subsurface long before the
actual movement on the surface could be detected.
The resistivity decrease is mainly due to the
increase in the water-saturation of the subsurface.
Higher water-saturation decreases in most cases
the stability.
Erich Niesner
Lehrstuhl für Geophysik
an der MUL seit: 1982
Email: erich.niesner@unileoben.ac.at
www.unileoben.ac.at/~geophwww/niesner.htm
Landslides start suddenly, but quite a time
before there is a slow steady change in
the subsurface properties till the instability
condition, triggering the landslide event, is
reached. Sometimes there are small movements
short before the major event starts
and most of the forecasting systems are
based on the detection of these movements.
These measurements could be difficult since
the areas are often impassable and possible
fixpoints are in most cases far away. Also
landslides often start without prior detectable
movements. Therefore the aim of the
Forschungspartner:
ERKUDOK-Institut Gmunden – J.Weidinger
Projekt gefördert von der Österreichischen Akademie der
Wissenschaften
Forschungsschwerpunkte:
Geoelektrische und elektromagnetische Messverfahren
Spektrale Induzierte Polarisation
Geophysikalische Bohrlochmessungen
Entwicklung von Spezialsonden und Software