Transcript What Processes Change Landforms.

Chapter 4
Lesson 3
Weathering and Erosion
Weathering
• The process through which rocks or other
materials are broken down..
Types of Weathering
• Physical – caused • Chemical –
by pushing, pulling,
caused by
rubbing or
chemicals breaking
temperature
down rocks
changes.
– Often caused by
acid rain
– Or by certain
chemicals in
ground water
Frost Wedging
Erosion
• The process by which rock is moved from
one place to another.
Ways Rocks Can Erode
• Running water and waves
• Wind
• Ice (Glacial)
• Gravity
Water
• Water weathers rock by dissolving it
Water Erosion
• Rivers, streams, and runoffs
Mudslides & Landslides
• Mudslide –
movement of a large
amount of wet soil
and rocks down a
slope
– Happens after lots of
rain
• Landslide –
movement of a large
amount of dry rock
and soil down a slope
– May occur after
volcanic eruptions and
earthquakes
Landslides
Mudslides
Glaciers - a large mass of slowly
flowing ice
Cirque – steep hollow shape bowl
in a mountain formed by a glacier.
Deposition – process by which
eroded materials are dropped off in
another place
• Meanders – gentle
loops in rivers
• Sediment – particles
of soil and rock that
are carried along in
water
Nile Delta
• Headland – an area
of land that has water
on 3 sides.
• Sandbar – sand that
has been deposited over
time so long that it makes
a strip of sandy land.
• Flood – when water
• Floodplain – place
collects on land that is
that is easily flooded
normally dry
when river water rises
Wind Erosion
Protecting Shorelines
• Breakwater – a long
wall built out in the
ocean parallel to the
shore
• Fences and Dunes –
help keep sand dunes
from being eroded by the
wind