review#7weathering,erosion, deposition
TRANSCRIPT
L.O: weathering, erosion, deposition
When rocks are exposed to the environment, they can weather (break down).
Weathering when rocks breakdown into sediment (rock particles)
because they are exposed to the environment
Two kinds: physical and chemical weathering
Physical weathering rocks breakdown into sediment (small rock particles)caused by ice or biological activity
Chemical weathering: when the minerals in rocks dissolve or rust
from oxygen or acid rain
Chemical weathering happens in warm (hot) and humid (wet) environments.
Water is the greatest cause of weathering.
Small rocks weather faster than big rocks
Small rocks weather faster than big rocks
Rocks with soft minerals are less resistant to weathering
Rocks with harder minerals are more resistant to weathering
Soil is the result of the weathering of rocks and biological activity.
Erosion: when sediment (rock particles) are transported away.
Wind, gravity, ice (glaciers) and especially running water are agents
of erosion
Streams:
Streams (rivers) are moving water.
A stream’s velocity depends on its
• Gradient (slope)• Discharge (volume of water it carries)
The meander (outside of the bend) of a stream has the MOST erosion.
“C” has most erosion
Inside the bend (meander) has most deposition (“A”).
Which has more erosion? Which has more deposit?
Streams create V-shaped valleys
Streams create V-shaped valleys
Complete page 74.
Glaciers are huge slow-moving “rivers of ice”.
Glaciers transport all sizes of rocks as they move.
Glaciers create U-shaped valleys.
Deposition:When agents of erosion deposit the
sediments they carry.
Deposition: When agents of erosion deposit the sediments they carry.
Streams deposit sediment with horizontal sorting.
• As a stream slows down: the Largest, heaviest, Roundest and densest particles are deposited first.
Glaciers deposit unsorted (mixed-up rocks) piles .