Transcript Earth Science Review

Earth Science
Review
What are physical
features on the
earth’s surface?
Landforms
What are the four
agents that
constantly change
the earth’s
landforms?
•Water
•Wind
•Ice
•Mass movement
What is weathering?
The process of
breaking rock into
silt, sand, clay, and
other tiny pieces
What are these tiny
pieces called?
Sediment
How does water
weather rocks?
• Rivers can carve deep canyons
• Ocean waves can weather cliffs
• Freezes in cracks and expands
breaking the rock apart
• Acid rain dissolves rock
• Tumbles rocks into each other
What is erosion?
The process of
moving sediment
from one place to
another
What is the process
called of dropping it
into a new location?
Deposition
How does water
erode sediment?
• Waves take the sediment from the
cliffs to the beach
• Rainfall carries it to rivers and
streams
• Rivers carry it to their banks
• Some rivers carry it to their
mouths
What is a delta?
The new land that
has been deposited
in a triangle shape
near the mouth of a
river
What does wind
erode more quickly?
Dry soil instead of
wet soil
Where is this
greatest?
Where there is little
plant life to hold
sediment in place
What unusual
landforms can wind
erosion create?
•Tables
•Arches
•Columns
What are dunes?
Large mounds of
sand
What are beach
dunes caused by?
The constant blowing
of the sea breeze
What are glaciers?
Large thick sheets of
ice formed when
more snow falls
during the winter
than melts in the
summer
Why does a glacier
erode everything
under it?
It’s great size and
weight
What are the two
kinds of glaciers?
Valley and
Continental
Where are valley
glaciers found?
High in mountain
valleys
How do they erode?
They flow slowly
down the
mountainsides
What do they form?
A U-shaped valley
How many are left?
Very few and these
are melting quickly
What are continental
glaciers?
Thick sheets of ice
that cover large
areas of the Earth
What is mass
movement?
The downhill
movement of rock
and soil because of
gravity.
Give some examples
of mass movement
•Mudslides
•Landslides
•Avalanches
•Sinkholes
How does a landslide
or mudslide occur?
The force of gravity is
greater than the force
of friction holding the
soil
What is creep?
The slow movement
of soil downhill
How fast does it
move?
Only a few
centimeters each
year
What is a sinkhole?
A large hole in the
ground that opens
suddenly
How does a sinkhole
occur?
The limestone
beneath the surface
erodes and the land
over the weakened
area collapses?
How does erosion
and deposition effect
the landforms?
It can change them
or produce new
ones.
What are terminal
moraines?
The long ridges of
soil and rock left
behind by glaciers.
Give an example of
it.
Long Island or Cape
Cod
How are new islands
formed?
Volcanic eruptions
How does this
happen?
Slowly over time the
melted rock and ash
continue to be
deposited on top until
the it appears over the
surface of the water
The End