changing earth’s surface - weber school...
TRANSCRIPT
Erosion and Deposition
Erosion and
Depostition - Changing Earth’s Surface
- Changing Earth’s Surface -
Erosion and Deposition
Changing Earth’s Surface—
Shaping the land A. Weathering The breaking down of solid
rock into smaller particles.
B. Erosion: The movement of the products
of weathering form where they were formed to a
different location.
C. Deposition: The accumulation of eroded
sediments.
- Changing Earth’s Surface
Erosion and Deposition
Wearing Down and Building Up
Weathering, erosion, and deposition act together in a cycle
that wears down and builds up Earth’s surface.
- Changing Earth’s Surface
Erosion and Deposition
Agents of erosion.
1. Gravity:
2. Glaciers
3. Wind Erosion
4. Water erosion:
- Changing Earth’s Surface
Erosion and Deposition
Gravity Erosion
--Mass Movement
The different types of
mass movement
include landslides,
mudflows, slump, and
creep.
- Changing Earth’s Surface
Erosion and Deposition
Mass Movement Activity
- Changing Earth’s Surface
Website: phschool.com
Webcode: cfp-2031
Erosion and Deposition
Type of Mass
Movement Speed Slope
Comparing and Contrasting
As you read, compare and contrast the different types of
mass movement by completing a table like the one below.
Landslide rapid steep
Mudflow rapid gentle to steep
Slump rapid steep
Creep slow gentle to steep
Mass Movement
- Changing Earth’s Surface
Erosion and Deposition
Water Erosion Precipitation over the United States averages about 75 cm
per year. About 22.5 cm becomes runoff. Generally, more
runoff means more erosion.
Erosion and Deposition
Water Erosion
Water flowing across the land runs together to form rills,
gullies, and streams.
- Water Erosion
Erosion and Deposition
Erosion by Rivers
A waterfall forms where a flat layer of tough rock lies over a
layer of softer rock that erodes easily. When the softer rock
erodes, pieces of the harder rock above break off, creating
the waterfall’s sharp drop.
- Water Erosion
Erosion and Deposition
Erosion and Sediment Load
A river erodes sediment from its banks on the outside curve
and deposits sediment on the inside curve.
- The Force of Moving Water
Erosion and Deposition
Erosion by Rivers
Erosion often forms meanders and oxbow lakes where a
river winds across its floodplain.
- Water Erosion
Erosion and Deposition - Water Erosion
The Course of a River
The slope and size of a
river, as well as the
sediment it carries,
determine how a river
shapes the land.
Erosion and Deposition
Deposits by Rivers
Deposition creates landforms such as alluvial fans and
deltas.
- Water Erosion
Erosion and Deposition - Water Erosion
Groundwater Erosion
Chemical weathering of limestone and groundwater erosion
can create a limestone cave.
Erosion and Deposition
How Water Erodes
Most sediment washes or falls into a river as a result of mass
movement and runoff. Other sediment erodes from the
bottom or sides of the river. Streams carry sediment in
several ways, as shown in the diagram.
- The Force of Moving Water
Erosion and Deposition
Water Erosion and Sediment Load
A river’s slope is usually greatest near the river’s source. As
a river approaches its mouth, its slope lessens.
- The Force of Moving Water
Erosion and Deposition
Sediment on the Move
The speed, or velocity, of a
stream affects the size of the
sediment particles the stream
can carry.
- The Force of Moving Water
Erosion and Deposition
Erosion by Waves
Waves shape the coast through erosion by breaking down
rock and transporting sand and other sediment.
- Waves
Erosion and Deposition
Erosion by Waves
Erosion and deposition create a variety of features along a
coast.
- Waves
Erosion and Deposition
Deposits by Waves
Waves shape a coast when they deposit sediment, forming
coastal features such as beaches, spits, and barrier
beaches.
- Waves
Erosion and Deposition
Glacier Erosion
A continental glacier is a glacier that covers much of a
continent or large island.
Erosion and Deposition
Glacier Erosion:
How Glaciers Form and Move During the last ice age, a continental glacier covered most of
northern North America.
Erosion and Deposition
How Glaciers Shape the Land
As a glacier moves, plucking breaks pieces of bedrock from
the ground.
- Glaciers
Erosion and Deposition
How Glaciers Shape the Land
Erosion by glaciers can carve a mountain peak into a sharp
horn and grind out a V-shaped valley to form a U-shaped
valley.
- Glaciers
Erosion and Deposition
How Glaciers Shape the Land
As glaciers advance and retreat, they sculpt the landscape
by erosion and deposition.
- Glaciers
Erosion and Deposition
How Wind Causes Erosion
Wind erosion moves sediment particles of different sizes in
the three ways shown below.
- Wind
Erosion and Deposition
Wind Deposition
Wind erosion and deposition may form sand dunes and loess
deposits.
- Wind