Transcript Chapter 2, Section 2 - deercreekintermediate.org

Chapter 2, Section 2
Forces Shaping Earth
The Ring of Fire
The Ring of Fire is on the rim of the Pacific Ocean.
80% of all earthquakes and volcanoes occur here.
April 16, 2016
6.2 magnitude
Inside the Earth
There are four
basic layers of
the earth’s
interior:
The Inner Core
(solid)
The Outer Core
(molten)
The Mantle
(magma)
The Crust
(solid land)
What is the Earth made of?
Water covers 72% of the Earth’s surface.
Only 28% is land.
The Pacific Ocean
The largest ocean
is the Pacific.
Its name comes
from the Spanish
word for
“Peaceful.”
It was named by
the explorer
Ferdinand Magellan.
The Atlantic Ocean
The Atlantic Ocean
takes its name
from the
Ancient Greek
Titan
“Atlas,”
who was
condemned
to hold the sky
on his shoulders.
The Indian Ocean
The Indian Ocean
gets its name
from the
Ancient
Sanskrit
word
“Sindhu,”
which means
River.
The Arctic Ocean
The Arctic Ocean
gets its name
from the Ancient
Greek word
“Arktos,”
which means
Bear
(the constellation,
not the animal).
“Water, water, everywhere…”
“…nor any drop to drink.”
from the poem
The Rime of the
Ancient Mariner
by Samuel Coleridge Taylor
(1798).
97 % of Earth’s water is salty.
2% is frozen at the Poles.
Only 1% is usable to humans.
atmosphere
The atmosphere is
a thick layer of gases
surrounding the Earth.
It provides oxygen for
people and animals
and carbon dioxide
for plants.
It comes from the Greek
words “atmos” (vapor)
and “sphere” (circle).
landforms
Landforms are the
Earth’s physical
features. They
include
mountains,
hills,
plateaus,
and
plains.
continents
The
continents
are
the
Earth’s
largest
landforms.
They
include:
• Asia, meaning “Rising.”
• Europe, meaning “Setting.”
• Africa, meaning “Hot” or
“Dusty.”
• Australia, meaning “Southern
Land.”
• Antarctica, meaning “Opposite
the Arctic.”
• North and South America, named
for explorer Amerigo Vespucci.
volcano
A volcano
is a rupture
in the Earth’s
crust, which
allows magma,
ash, and gases
to escape from
below the
surface.
earthquake
An earthquake is a sudden movement of the Earth’s
crust, usually causing widespread damage.
Santiago, Chile 2010
faults
Weak places in the Earth’s crust are called faults.
The plates push against each other, causing earthquakes.
The two worst are the San Andreas in southern California and the New Madrid in Missouri.
plate tectonics
The theory of
plate tectonics
says the
landmasses
on the Earth’s
surface,
(or crust)
are constantly
moving.
Undersea mountains
The tectonic plates only move about 2 inches a year.
Magma and plate buckling create new mountains
and even island chains, like Hawaii.
Pangaea
Geographers theorize
that 200 million years
ago, there was a
“supercontinent”
they call Pangaea.
The name comes from two
Greek words that mean
“All Earth.”
Laurasia
As Pangaea broke up, the northern landmass became Laurasia,
named for the St. Lawrence River at its center.
Gondwanaland
The southern landmass became Gondwanaland,
taken from the Sanskrit word for forest.
Continental drift
weathering
Weathering
is the process of
breaking down
rock through wind,
rain, and ice.
The rocks combine
with decayed animal
and plant matter
to become soil.
erosion
Erosion is the process of moving soil.
It is transported and deposited elsewhere.
A
river
delta
can be
created
by soil
deposited
downstream.
Mississippi River Delta