Chapter 13
Weathering, Karst
Landscapes, and Mass
Movement
Geosystems 5e
An Introduction to Physical Geography
Robert W. Christopherson
Charlie Thomsen
Weathering, Karst Landscapes,
and Mass Movement
Landmass Denudation
Weathering Processes
Karst Topography and Landscapes
Mass Movement Processes
Landmass Denudation
Geomorphic Models of Landform Development
Dynamic Equilibrium View of Landforms
Delicate Arch, Arches NP, Utah
Differential Weathering
Regolith, Soil, and Parent Materials
Figure 13.5
Figure 13.5
b) Example of components in
(a).
Weathering Processes
Factors Influencing Weathering Processes
Physical Weathering Processes
Frost heave, crystallization, temperature change,
pressure-release jointing
Chemical Weathering Processes
Hydrolysis, solution weathering, oxidation
Physical Weathering
Frost Action
Forms talus slopes in mountain areas
Figure 13.7
Figure 13.8
Exfoliation
in
Granite
Overburden removed from
buried plutons
Great
Arches
Half Dome,
Yosemite
Figure 13.11
Frost heave, Yosemite NP.
Glacier Point climbing area.
1996 Rockfall
162,000-ton granite slab.
160 mph speed.
Killed several people.
Canyon de Chelly
Crystallization plus
Differential weathering
Chemical Weathering
East side of Sierras.
Alabama hills in front.
Mt Whitney in back.
Physical
weathering on
Mt. Whitney
in background
Chemical
weathering on
Alabama Hills
in foreground
Formed from the same plutons. Difference is age of exposure,
Air temperature, and glaciation.
Figure 13.12
Little Joe, Ponderosa
Oxidation
Karst Topography and Landscapes
Formation of Karst
Lands Covered with Sinkholes
Caves and Caverns
Result of carbonation-solution weathering
Karst and Limestone Regions
Figure 13.14
Sinkhole and Tower Karst
Figure 13.17
Figure 13.18
Cavern Features
Figure 13.19
Cenote in Mexico
Mass Movement Processes
Mass Movement Mechanics
Classes of Mass Movements
Human-Induced Mass Movements (Scarification)
Slope Mechanics and Form
Figure 13.3
Shear stress and strength
Mass movements occur when shear stress
exceeds shear strength
Shear stress = mass x gravity x sin (slope)
Water
Increases shear stress by adding mass
Decreases shear strength by lubricating
sliding layers
Mass Movement Classes
Figure 13.21
Soil Creep
Figure 13.27
Solifluction
Figure 17.23
Madison River Landslide
1959 mag 7.5 earthquake
Created Quake Lake
Killed 28 people
Figure 13.20
Debris Avalanche
St. Elias Range, Alaska
Figure 13.24
Nevado Huascaran
Cordillera Blanca, Peru
1970 Earthquake
Failed near summit
Vertical drop of 4,100 m
Horizontal distance of 16 km
Velocities > 186 mph
Killed > 20,000 people
1962 avalanche killed 4,000
End of Chapter 13
Geosystems 5e
An Introduction to Physical Geography
Robert W. Christopherson
Charlie Thomsen