Transcript Mass Movement
RATES OF WEATHERING
Factors of Rates of Weathering
1. Parent Material (The rocks themselves) - Igneous and
metamorphic most resistant, sedimentary least resistant
because of pores.
2. Surface Area
3. Climate - Warm and wet = chemical weathering
Cold and Dry = mechanical weathering
EROSION - The breakup and removal of rock by moving
natural agents (rivers, glaciers, wind, water)
• General term used
for rock fragments
moving down a
• What is causing this
erosion to occur?
• Can happen either
fast or slow.
Talus Slopes - Large piles of rock
that break off and pile up at the
bottom of a hill
• Sudden movement of
masses of loose rocks.
• Triggered by:
Mudflow - Fast
large masses of
Occur in dry, mountainous regions
during fast, heavy rainfalls or
Rockfall - Rocks falling from a steep
cliff. This is the most rapid type of
Creep - very slow down hill movement of weathered rock
Usually goes unnoticed unless it hits a building or something.
Creeps can include rocks, plants, buildings, etc.
Soils - soil science = PEDOLOGY
Most important result of weathering and erosion is soil
Two general classes of soil:
A. residual soil - soil made from local bedrock
B. Transport soil - soil that was moved by wind, or glacier
Factors determining soil
1. Climate - Rainfall amount and temperature
2. Parent Rock - Type and chemical composition
3. Vegetation - Roots and Leaves
4. Topography - hilliness, etc.
5. Time - how long to develop