Erosion & Deposition Erosion • the process by which natural forces move weathered rock and soil from one place to another.
Download ReportTranscript Erosion & Deposition Erosion • the process by which natural forces move weathered rock and soil from one place to another.
Erosion & Deposition
Erosion
• the process by which natural forces move weathered rock and soil from one place to
another
Causes
of Erosion
• Gravity • Running water • Wind • Glaciers
Causes of Erosion
•
Gravity =
force that moves rock and other materials
downhill
–
Mass movement
—process of moving sediment downhill – May be fast or slow
Causes of Erosion
•
Gravity
– Force that moves rock and other materials downhill – Mass movement—process of moving sediment downhill – May be fast or slow –
Types of mass movement:
•
Landslides
—rock & soil slide
quickly
down a steep slope
Causes of Erosion
•
Gravity
– Force that moves rock and other materials downhill – Mass movement—process of moving sediment downhill – May be fast or slow –
Types of mass movement:
•
Mudflows
—rapid downhill movement of a mixture of
water
, rock, and soil
Causes of Erosion
•
Gravity
– Force that moves rock and other materials downhill – Mass movement—process of moving sediment downhill – May be fast or slow –
Types of mass movement:
•
Slump — one large mass
of rock and soil suddenly slips down a slope
Causes of Erosion
•
Gravity
– Force that moves rock and other materials downhill – Mass movement—process of moving sediment downhill – May be fast or slow –
Types of mass movement:
•
Creep — very slow
downhill movement of rock and soil
Causes of Erosion
•
Running Water = #1
agent of erosion
Causes of Erosion
•
Running Water
– #1 agent of erosion Colorado River Grand Canyon –
Types of running water:
•
Streams
– Small streams = creeks – Large streams = rivers
Causes of Erosion
•
Running Water
– #1 agent of erosion –
Types of running water:
• • Streams
Waves
Causes of Erosion
•
Wind =
Blows sediment Dust Bowl Sand dunes
Causes of Erosion
•
Glaciers =
Large masses of moving
ice
– Movement changes the land Alaska beneath them
Deposition
• the natural process of laying
down
sediments in a new
location
– creates
new landforms
Deposition
• the natural process of laying
down
in a new
location
sediments –
creates new landforms:
•
Oxbow lake —
deposition
blocks off
part of a river
Deposition
• the natural process of laying
down
in a new
location
sediments –
creates new landforms:
•
Delta —
sediment is deposited at the
end
of a river
Deposition
• deposited sediments are laid down in
layers
• layers of sediment are
compacted
under pressure and eventually form
sedimentary
rock
Deposition
• • deposited sediments are laid down in
layers
Layers of sediment are
compacted
under pressure and eventually form
sedimentary
rock Sedimentary rocks are like ogres and onions…they have
layers
.
Deposition
• • deposited sediments are laid down in layers Layers of sediment are compacted under pressure and eventually form sedimentary rock
Most fossils are found in sedimentary rocks because organisms get covered and preserved by the layers then mineral replacement occurs over time.
Weathering, erosion and deposition
are all part of a never-ending cycle that constantly shapes and reshapes the land.
Weathering, erosion and deposition
are all part of a never-ending cycle that constantly shapes and reshapes the land.
Destructive forces
—break down
Constructive forces
—build up
Weathering, erosion and deposition
are all part of a never-ending cycle that constantly shapes and reshapes the land.
Destructive Forces
Weathering
Breaks down rock
Destructive Forces
Erosion
Carries sediment away
Constructive Forces
Deposition
Takes sediment to a new location to build new rock layers