Post on 23-Feb-2016
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Aim: How are Landscapes (landforms) formed?
•Landforms are the results of interaction of tectonic forces , processes of weathering, erosion, deposition, and climate.
What are the characteristics of a landscape?
1. Elevation2. Bedrock3. Stream drainage pattern4. Soil characteristics 5. Slope
All these help to define the landscape pattern of a region
What factors influence landscape development?
1. Uplifting forces (tectonic forces)- originate beneath or within Earth’s lithosphere.
2. Leveling or destructional forces - lower and level out Earth’s surface by breaking the landmasses, transporting sediments along Earth’s surfaces, and depositing sediments.
Forces Source of Energy
Uplifting- Volcanic actions, earthquakes and any other movement associated with plate interactions
Earth’s interior due to radioactive decay materials and from residual heat from Earth’s formation
Leveling- Weathering, erosion, deposition, and sinking
Energy from the sun-insolation-and gravity.
Types of Landscape
Destructive Forces (Leveling) Constructive Forces (Uplifting)
More on Landforms
Leveling Forces Leveling Forces
The topographic pattern streams take are not necessarily totally random. They are affected by rocks and their structures.
Drainage Patterns
Factors affecting Landscape Features
•Wherever earthquakes and volcanic activities occurs, uplifting is usually the dominant force.•Slopes rise up
Drainage Patterns
• drainage pattern: the arrangement of a river and its tributaries
• types:– dendritic: resembles the branches of a tree or veins in
a leaf
Drainage Patterns (cont.)
– rectangular: when tributaries have frequent 90o
bends and tend to join other streams at right angles; develops on regularly fractured rock
Drainage Patterns (cont.)
– radial: when the streams diverge outward like spokes of a wheel; formed on high conical mountains
Stream Pattern and Geologic Structures