Sedimentary Landforms Flashcards
Landforms composed of sandstones and siltstones
Arenaceous landforms
Most resistant
Low drainage density
Chemical weathering resistant
Low infiltration
Permeability through discontinuities
Silica cemented
Example of an arenaceous landforms
Appalachian mountains
Colorado plateau
Less resistant cement
Locally high rates of infiltration- high permeability
Rapid weathering
Can be very weak mechanically and chemically
Cliff-forming
Iron-oxide cement
Chemically and mechanically weak
Cliff-forming
Calcium carbonate cement
Composed of clay and shale, has low relief and support varies with the presence of water
Argillaceous landforms
Argillaceous landforms typically divided into two groups:
Under humid conditions/high moisture, shallow water table and continuous vegetation cover
Under arid/semi-arid, moisture intake is limited into the surface and sparse vegetation cover
Low slope angle (<8°)
Moderate drainage density
Moderately resistant to surface erosion
Drainage pattern – Dendritic (Usually)
Dominantly controlled by the slope
Argillaceous landforms- Humid
Differing behavior of layers
“Badlands” terrain
High drainage density
Low overall relief with short, steep slopes – separated from basal low angle slopes by sharp breaks
Argillaceous landforms- Arid
German form of the Slovene word “Kras” meaning craggy or stony ground.
Karst
The process of dissolving limestones forming underground drainage.
Karstification
The formation of karst requires the following
Humid weather
“Hard” and thick limestone beds
Thin or non-existent soil cover
Well jointed limestones
T or F. Chalk formation from SE UK and N France are true karst.
F. Not true karst
Refers to small solutional sculpture
Karren in german
Lapies in French
Individual pits produced by rain drops
rainpits
