Lecture Overview
ƒ Definition: geomorphology
ƒ Geomorphic mapping
ƒ Review: Landslide terminology & classification
systems
ƒ Characteristics of landslides
ƒ Mapping of landslide types
ƒ Examples of geomorphic mapping in landslide studies
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Linkages
Process
Form
Material
Rotmoostal /
Gurgler Tal
Geomorphology is the science of relief forms, forming materials and the
2changing processes.
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Aerial photography of Bíldudalur, view
to North
Iceland - Photopraphs
Bíldudalur,
Westfjords
Glade & Jensen 2002
(Photo: Matz Wibelund)
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Geomorphic mapping
Geomorphological map
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Glade & Jensen (2004)
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Soil creep / solifluction
Sediment origin
Appl. Model
Assumption: 25mm/yr with 0.5m
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Otto & Dikau, 2004
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
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3
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
Otto & Dikau, 2004
Thematic components of the geomorphologic map of
the Turtmann valley
Thematic layers
Temporal scale
Map legend symbol
Information source
Geomorphologic
Process
Activity 1 in the last 5
years (red)
No Activity in the
last 5 years (black)
Point symbols (red or
black)
Field observation,
state
of
activity
according
to
indicators (see text)
Singular Landform
Partly specified
Line or point symbols
Field observation
Geomorphography
Not specified
Line symbols
Field
observation,
analysis of DTM and
topographic maps
Process Domain
All scales (active and
past processes)
Coloured polygons
Field observation,
process recognition,
material properties,
inferring of past
processes based on
landform geometry
and material.
Hydrology/
Glaciology
Not specified
Line symbols
polygons
Field observation,
topographic maps
Subsurface Material
Not specified
Hatched polygons
(steps and breaks of slope,
valleys and drainage
ways)
1Types
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and
Field observation
of activity: continuous, intermittent, episodic, singular
Otto & Dikau, 2004
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
Qualitative sediment flux model of the Brändjitälli hanging
valley
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4
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
9
Otto & Dikau, 2004
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
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Otto & Dikau, 2004
5
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
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Otto & Dikau, 2004
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
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Otto & Dikau, 2004
6
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
Otto & Dikau, 2004
13
Example: Geomorphic mapping in the Turtmann
valley, Switzerland
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Otto & Dikau, 2004
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Example: Geomorphic mapping in the Turtmann
valley, Switzerland
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Otto & Dikau, 2004
Example: Sediment storage - Rain valley, Germany
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8
Linking storage – process / Activity of storages
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Mössingen-Öschingen
Geomorphic mapping in landslide studies
GMK 25
Leser 1972
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9
Landslide terminology
Crown
Main scarp
Top
Head
Minor scarp
Main Body
Foot
Tip
Toe
Zone of accumulation
Depletion
Surface of rupture
Depleted mass
Surface of separation Accumulation
Zone of depletion
Flank
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Adopted from Cruden & Varnes, 1996
Landslide classifications
ƒ Material: Rock, Soil, Lithology, structure,
Geotechnical properties
ƒ Geomorphic attributes: Weathering, Slope form
ƒ Landslide geometry: Depth, Length, Height etc.
ƒ Type of movement: Fall, Slide, Flow etc.
ƒ Climate: Tropical, Periglacial etc.
ƒ Water: Dry, wet, saturated
ƒ Speed of movement: Very slow, slow etc.
ƒ Triggering mechanism: Earthquake, rainfall, etc.
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10
Landslide classifications (1/3) – Sharpe 1938
ƒ
ƒ
ƒ
ƒ
Material: earth, rock
Movement: flow, slip
Velocity: slow to very rapid
Water/ice content
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Landslide classifications (2/3) – Varnes 1978
ƒ Material: bedrock, debris, earth
ƒ Movement: fall, topple, slide, flow, complex
ƒ Secondary: water content, velocity
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Landslide classifications (3/3) – Wieczorek 1984
YESF:
Y = Dormant-Young
E = Earth
S = Slide
F = Flow
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Landslide
characteristics:
Morphology
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12
Landslide characteristics: Vegetation
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Landslide characteristics: Drainage
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13
Landslide characteristics: Active vs. Non-active
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Mapping Landslide Types
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14
Mapping Landslide Types
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Field methods – topographic measurements
ƒ Tachymeter
Petrahn 1996
Petrahn 1996
Keaton & de Graff
1996
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Großmann 1983
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Field methods – topographic measurements
ƒ Tachymeter
Petrhn 1996
Keaton & de Graff 1996
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Natural Hazards/Risk & Geomorphology
Geomorphologic mapping
ƒ Identification of distributions of processes
ƒ Estimation of temporal occurrence
ƒ Analysis of material
ƒ Assessment of sediment storage
ƒ Basic information for process modeling
Geomorphologic process studies
ƒ Verification of assumptions
ƒ Estimation of sediment production
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16
Mapping
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Demoulin & Glade 2004
Field methods – topographic measurements
ƒ GPS
Period: Okt 01 – Mai 02
Okt-Dez:
Jan:
Feb:
March:
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no movement
3cm – snow melting
~30cm – heavy rainfalls
no movement
Demoulin & Glade 2004
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Geomorphic mapping
ƒ Legend of Terhorst (2001)
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Geomorphic mapping
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Geomorphic mapping
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Geomorphic mapping in landslide studies
General geomorphological
Mapping with focus on
landslides
1:50,000
(Kallinich 1999)
Only cuesta and
landslide heads were mapped
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19
Mössingen-Öschingen
Geomorphic mapping in landslide studies
39
Geomorphic mapping in landslide studies
Geological profile derived
from geomorphological
mapping
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20
Mössingen-Öschingen
Geomorphic mapping in landslide studies
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Mössingen-Öschingen
Geomorphic mapping in landslide studies
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21
Mössingen-Öschingen
Geomorphic mapping in landslide studies
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Mössingen-Öschingen
Elements at risks - Houses
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Mössingen-Öschingen
Elements at risk – Classified regions
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Mössingen-Öschingen
Elements at risk – Classified regions
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Mapping of Rockfall impact – (1/2)
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Wieczoreck et al. (2000)
Mapping of Rockfall impact – (2/2)
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Wieczoreck et al. (2000)
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Conclusion
ƒ Form – Geomorphometric features
• Approximation of age
• Topographic measurements (Tachymeter, GPS)
ƒ Material – Near subsurface material
• 1m drillings
ƒ Process domains
• Dominant process – spatially distributed
• Grade of activity
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References
ƒ Cruden, D.M. and Varnes, D.J. 1996: Landslide types and processes. In Turner,
A.K. and Schuster, R.L., editors, Landslides: investigation and mitigation,
Washington, D.C.: National Academey Press, 36-75.
ƒ Demoulin, A. and Glade, T. in prep.: Recent landslide activity in Manaihan,
Belgium. Landslides.
ƒ Glade, T. and Jensen, E.H. 2004: Landslide hazard assessments for Bolungarvík
and Vesturbyggð, NW-Iceland. Reykjavik: Icelandic Meteorological Office.
ƒ Glade, T., Kadereit, A. and Dikau, R. 2001: Landslides at the Tertiary
escarpement of Rheinhessen, Southwest Germany. Zeitschrift für
Geomorphologie, Supplement Band 125, 65-92.
ƒ Kallinich, J. 1999: Verbreitung, Alter und geomorphologische Ursachen von
Massenverlagerungen an der Schwäbischen Alb auf der Grundlage von Detailund Übersichtskartierungen.
ƒ Knödel, K., Krummel, H. and Lange, G., editors 1997: Geophysik. Berlin:
Springer Verlag.
ƒ Reynolds, J.M. 1997: An Introduction to Applied and Environmental Geophysics.
Chichester, UK: John Wiley & Sons.
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References
ƒ Sharpe, C.F.S. 1938: Landslides and Related Features - A Study of Mass
Movements of Soil and Rock. New York. pp. 137.
ƒ Selby, M.J. 1993: Hillslope materials and processes. Oxford: Oxford University
Press.
ƒ Otto, J.-C. and Dikau, R. 2004: Geomorphic system analysis of a high mountain
valley in the Swiss Alps. Zeitschrift für Geomorphologie N.F. 48, 323-341.
ƒ Terhorst, B. and Kirschhausen, D. 2001: Legends for mass movements in the
MABIS-Project. Zeitschrift für Geomorphologie, Supplement Band 125, 177-192.
ƒ Varnes, D.J. 1978: Types of slope movement.
ƒ Wieczorek, G.F. 1984: Preparing a Detailed Landslide-Inventory Map for Hazard
Evaluation and Reduction. Bulletin of the Association of Engineering Geologists
21, 337-342.
ƒ Wieczorek, G.F., Snyder, J.B., Waitt, R.B., Morissey, M.M., Uhrhammer, R.A.,
Harp, E.L., Norris, R.D., Bursik, M.I. and Finewood, L.G. 2000: Unusual July
10, 1996, rock fall at Happy Isles, Yosemite National Park, California. GSA
Bulletin no.1, 75-85.
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