Geomorphology Flashcards
Geomorphology
the study of the physical features of the surface of the earth and the processes that shape them
Horizontally layered rocks have their origin either as deposited ___ or as ______
Sediments
Layers of Lava
Canyon landscapes
where horizontal layers erode at different rates
Resistant rocks form steep cliffs, less resistant = gentle slopes
Uses of canyons
can be dammed up to make dams
hydro-electric power stations
tourist attractions
Karoo landscapes
develop from canyon landscapes
Features: plateau, escarpment, mesa, butte, conical hill
The difference between a mesa and a butte
Mesa= longer than it is high Butte= higher than it is long
Batholiths and laccoliths are exposed as…
domes
A dome may develop into a ___
Tor
How a Tor develops
- -The dome is weathered by chemical weathering below the surface
- -The joints by weathering (water seeps through cracks and freezes example)
- -Overlying rock stripped away by erosion, revealing a Tor
How are igneous rocks formed
When magma cools down and solidifies
Features of a slope
Crest (concave shape)
Cliff
Talus slope
Pediment (Convex shape near base)
Parallel slope retreat
Concept that slope angle and lengths remain the same as the slope moves backwards. Constantly parallel to its previous position
Mass movements
Movement of weathered material down a slope under the influence of gravity
Factors influencing mass movement
Gradient/steepness of the slope
Moisture in the soil (increases chance of movement)
Vegetation (more stops movement)
Rock structure (sediment moves, solid rock less likely)
Types of mass movement
Soil creep (slowest movement)
Solifluction (water saturated soil)
Landslides (Mass of land breaks and plunges)
Rockfalls (Rapid movement of broken rocks)
Mudflows (Stream of mud)
Slumps (slope failure)
