GEOGRAPHY
- GRADE 11 -
GEOMORPHOLOGY
- Topic 3 -
Page 126-175
Define the term Topography
It is the terrain or landscape. It describes the physical features of an area of land
Landscape is a result of three factors:
1. Geology - Rocks, Soil
2. Climate - Weather Patterns
3. Isostatic Adjustment - Rate of Uplift
Define the phrase Horizontally Layered Rock
Flat layers (Strata) of rock material formed on top of each other
How Horizontally Layered Rocks form
When horizontal sedimentary rocks are uplifted without changing their horizontal position
When lava flows on the surface cools forming a horizontal layer of igneous rock
When a sill (Horizontal igneous landform) is exposed to the surface
The four Landscapes that form from Horizontally Layered Rocks:
1. Hilly Landscape
2. Basaltic Landscape
3. Karoo Landscape
4. Canyon Landscape
, Scarp Retreat Process
Mass Wasting is the downhill movement of rock and soil material due to gravity. It can be slow or
rapid for example a landslide
Sheet Erosion is the uniform removal of soil in thin layers, and it occurs when soil particles are
carried evenly over the soil surface by rainwater that does not infiltrate into the ground
Cuesta Homoclinal Ridge Hogsback
Homoclinal Ridge - Ridge formed from inclined strata
Homoclinal Landscape - A landscape formed of inclined strata that are tilted by the same degree of
dip in the same direction
Dip and Scarp Slope
Surface erosion exposes the inclined strata. This results in a scarp slope and a dip slope
This formation is a dependant on the angle of the resistant layers
Erosion is less on the dip slope
The scarp slope is eroded due to sheetwash and mass wasting
- GRADE 11 -
GEOMORPHOLOGY
- Topic 3 -
Page 126-175
Define the term Topography
It is the terrain or landscape. It describes the physical features of an area of land
Landscape is a result of three factors:
1. Geology - Rocks, Soil
2. Climate - Weather Patterns
3. Isostatic Adjustment - Rate of Uplift
Define the phrase Horizontally Layered Rock
Flat layers (Strata) of rock material formed on top of each other
How Horizontally Layered Rocks form
When horizontal sedimentary rocks are uplifted without changing their horizontal position
When lava flows on the surface cools forming a horizontal layer of igneous rock
When a sill (Horizontal igneous landform) is exposed to the surface
The four Landscapes that form from Horizontally Layered Rocks:
1. Hilly Landscape
2. Basaltic Landscape
3. Karoo Landscape
4. Canyon Landscape
, Scarp Retreat Process
Mass Wasting is the downhill movement of rock and soil material due to gravity. It can be slow or
rapid for example a landslide
Sheet Erosion is the uniform removal of soil in thin layers, and it occurs when soil particles are
carried evenly over the soil surface by rainwater that does not infiltrate into the ground
Cuesta Homoclinal Ridge Hogsback
Homoclinal Ridge - Ridge formed from inclined strata
Homoclinal Landscape - A landscape formed of inclined strata that are tilted by the same degree of
dip in the same direction
Dip and Scarp Slope
Surface erosion exposes the inclined strata. This results in a scarp slope and a dip slope
This formation is a dependant on the angle of the resistant layers
Erosion is less on the dip slope
The scarp slope is eroded due to sheetwash and mass wasting
