Influence of Rock Types on Landscape (Using West Malaysia as an Example)
The type of rock underlying a
region plays a key role in shaping its landscape. Harder rocks resist erosion
and form highlands, while softer rocks wear away faster, creating lowlands.
Here’s how different rocks shape West Malaysia’s terrain:
1. Resistant Igneous &
Metamorphic Rocks
- Granite:
- Forms the Main Range and Eastern
Range (peaks over 2,000 feet).
- Creates smooth slopes and rounded
hilltops due to slow weathering.
- Quartzite (metamorphosed
sandstone):
- Extremely hard; forms Gunong
Tahan (7,186 ft), the highest peak in West Malaysia.
2. Less Resistant Sedimentary
Rocks
- Shale, Schist, Sandstone:
- Softer and erode faster, forming lower,
rounded hills.
- Example: Rolling hills in areas with
shale/sandstone.
3. Limestone
- Permeable but Resistant:
- Dissolves in water (karst process), but
forms steep-sided hills due to vertical erosion.
- Example: Dramatic limestone hills
near Ipoh and Perlis (e.g., Langkawi’s
karst towers).
4. Recent River Sediments
- Alluvial Deposits:
- Soft, loose materials (sand, silt)
form flat plains along rivers.
- Example: Fertile plains used for
agriculture.
Key Concepts
- Resistance to Erosion:
Harder rocks (granite, quartzite) = highlands.
- Permeability:
Limestone dissolves but resists surface erosion, creating karst
landscapes.
- Rock Type vs. Landform:
|
Rock Type |
Landform |
|
Granite/Quartzite |
High mountains, rounded
peaks |
|
Shale/Sandstone |
Low, rounded hills |
|
Limestone |
Steep karst hills |
|
River sediments |
Flat plains |
Why It Matters:
Understanding rock types helps explain why landscapes vary—from towering peaks
to fertile plains—and guides land use (e.g., farming on plains, tourism around
karst formations). 🌄