Potoška planina landslide

Monitoring of Potoška planina landslide
(Karavanke Mountains, NW Slovenia)
Tina Peternel
Geological
Survey of
Slovenia
Proceedings of the 2nd Regional
Symposium on Landslides, Belgrade, 2015
Geographical location:
The Potoška planina landslide is situated in the Karavanke
mountain ridge (NW Slovenia), above the village Koroška Bela.
18.5.2015
2
Potoška planina landslide

-
Main characteristics of Potoška planina landslide (estimated):
Length: up to 500 m
Width: 200 - 300 m
Average depth: 10 – 15 m
Estimated volume of the sliding mass: 1.8 x106 m3
18.5.2015
(Jež
et al., 2008)
3
J. Jež
Geological conditions
18.5.2015
(Jež
et al., 2008)
4
Slope mass movements in the Potoška planina
- The upper part of landslide is subjected to rockslides
5
Slope mass movements in the Potoška planina
- The main body of landslide is characterized by a more
complex dynamic and is presumed to be slow-motion slip.
6
Slope mass movements in the Potoška planina
- The toe of landslide represents the most active part of
landslide. The sliding mass is composed of tectonically
deformed and weathered bedrock and talus material.
7
The activity of landslide is evidenced by…
18.5.2015
8
In the past, the Potoška planina landslide was
investigated with…
RADAR
INTERFEROMETRY
+ GNSS
Milanič, 2011
Komac et al. 2014: Coupling of GPS/GNSS and radar interferometric data for a
3D surface displacement monitoring of landslides; Landslides
18.5.2015
9
MONITORING OF POTOŠKA PLANINA LANDSLIDE
In order to understand the specifics of a sliding processes, to
assess the surficial displacement rates and changes in the
surface topography and to assess the landslide extend we
applied periodical monitoring using:
• In – situ measurements (geological mapping, etc.)
• Rain-gauge station
• Tachymetric measurement using a total station
• UAV photogrammetry based on structure-from-motion and
multi view stereo photogrammetric techniques
• Terrestrial laser scanning (TLS)
• GNSS data acquired from I2GPS station
18.5.2015
10
UAV photogrammetry
Microdrone md4-1000
Ground control points
18.5.2015
Olympus Pen E-P1 camera
Leica GPS
11
Tachymetric measurement using a total station
18.5.2015
12
Results so far …
• Surficial displacement - based on direct visual
image comparison of two orthophotos (Powers et
al., 2006)
• Elevation and volume change - to examine the
elevation changes between the two measurements,
the elevations of the second acquisition DEM were
subtracted from the first one on a cell-by-cell basis.
18.5.2015
13
Surficial displacement
1. observation period (July 2013 - October 2013)
• Observation period:
3 months
• 487 displacement
vectors
• the displacement
direction is
predominantly SW
• Horizontal
displacements with
magnitudes
between 0.1 and 1
m
18.5.2015
14
Surficial displacement
2. observation period (October 2013 – April 2014)
• Observation period: 7 months
• 444 displacement vectors
• displacement
direction: SW
• Horizontal
displacements
with
magnitudes: 0.3
- 1.8 m
18.5.2015
15
Surficial displacement
3. observation period (April 2014 – September 2014)
•
•
•
•
Observation period: 5 months
278 displacement vectors
displacement direction: SW
Horizontal displacements with
magnitudes: 0.3 - 1.02 m
18.5.2015
16
Tachymetric measurements
 The measurements of all object points were obtained in November
2012, July 2013, October 2013 and in April 2014.
 For convenience displacement vectors were converted to monthly
average displacement rates:
 1. time period: 0.002 – 0.2 m/month
 2. time period: 0.004 – 0.5 m/month
 3. time period: 0.1 – 0.3 m/month
18.5.2015
17
Comparison and verification
- the comparison of the displacement vectors and the
displacements obtained from tachymetric measurements
18.5.2015
18
Challenges, goals …
- correlation between amount of precipitation (provide by
rain-gauge system) and landslide daily displacements
(provide by GNSS antenna)
18.5.2015
19
Challenges, goals …
- to quantify displacement rates and volume changes in the
main scarp of landslide using TLS and photogrammetry
18.5.2015
20
Ongoing IPL project
18.5.2015
21
Thank you for your attention
Somehow you need
years
 Information
to recognize
[email protected]
something obvious
Tel. 00286 1 28 09 813
…
Geological Survey of Slovenia
Dimičeva ulica 14
SI – 1001 Ljubljana
18.5.2015
22