Download Plain

Lesson 22
What are plains and plateaus?
Imagine that you are flying in a
plane from New York to San
Francisco, California. You have
a window seat, so you can see
all the land formations of the
USA. What would you see?
The Rocky Mountains
The interior plains
Coastal plains
Dense forests
plateaus
Mountains, plains, and plateaus
are the main continental
landforms.
A landform is a physical feature
of the earth's surface.
Plains......
A Plain is a large flat area not
much higher than sea level.
Two main kinds:
coastal - along the coast line
interior- inland
All plains slope, but it is a gentle
slope. So gentle that they seem
to be flat.
Some plains have gentle rolling
hills.
Plains are formed in several
ways.
Erosion forms many. Uneven
elevated lands are worn away
through erosion.
Deposition forms others.
Deposition is when sediment is
dropped (deposited) in water,
and the land rises up, or the
water level drops. A large flat
area or plain remains.
Plateaus
A Plateau is a large flat region,
with a high elevation.
Most plateaus are found inland.
Some are found near the ocean,
usually ending with a cliff.
Most plateaus have canyons.
A canyon is a steep-sided valley
carved out by stream erosion.
Plateaus form by large areas of
the earth's crust being moved
upward
Some are made by lava flowing
down, evening out, and cooling,
forming a large, raised area.