1. The center of the earth consists of
hot rock and is called the inner core
(solid iron and nickel).
2. There is also an outer core (liquid
iron and nickel).
3. The next level is hot, molten rock
4. The layer that we walk on is the
1. The Crust
1. The earth’s outer layer of
2.5-20 MILES THICK!!
3.Has mountains, ocean floor,
volcanoes, and continents
2. The Mantle
1. The second layer between the
crust and outer core
2. Is solid rock except for the part
next to the crust, where there is
3. 1,800 MILES THICK!!
3. The Outer Core
1. The outer part of the core is
liquid and HOT!
2. It gets hotter the deeper you go
(around 9,000 degrees F in the
center—your oven only goes to
about 600 degrees F).
3. It’s so hot that rock melts.
Melted rock is called MAGMA.
4. 1,400 MILES THICK!
4. The Inner Core
1. 800 MILES TO CENTER!
2. Shaped like a ball, or sphere.
The inside of the
earth is very hot,
and it always
releases a lot of
This energy causes
things to move in the
earth (rocks, plates,
The earth has many
mountains, hills, rivers,
canyons, plateaus, and
many other things.
1. Plate Tectonics
a. Explains how plates (large
bodies of rock) move slowly around
the earth on partly melted rock
a. A large section of the earth’s
crust that moves as one unit
b. There are 8 large plates and
several smaller plates.
As these plates float, they move in three
different ways. Each way that they move has
a special name associated with the boundary
where two plates meet.
Fault -- the place where two plates meet.
Types of plate movement:
1. Convergent -- where two plates move
2. Divergent – where two plates are
3. Sliding – where the plates slide past one
Continental Drift Theory
• A guy named Alfred Wegener came up with
• This is that the continents move (drift)
toward each other and then away from each
• Before drifting away from each other, all
the continents were one big land mass
1. What are they?
a. An opening in the earth’s surface.
2. How do they form?
a. Magma (melted rock) from
the mantle sometimes pushes
b. The crust usually blocks it, but
sometimes it seeps through cracks
in the crust. When it builds up inside a
“magma chamber”, the pressure
starts to increase and then---BAM!!!
3. What happens after they erupt?
a. The magma explodes through a main vent in the
b. A deep hole called a crater is often
left on top of the volcano.
c. The erupting magma is called lava.
d. Gases, volcanic bombs, ash, and melted rock also
burst from inside the volcano.
e. The lava layers and ash layers build up around the
outside of the volcano.
4. Interesting Facts:
a. Hawaii was formed by volcanoes
erupting in the Pacific Ocean.
b. The two types of volcanoes are erupting and
c. Lava can flow up to 50 mph but usually just flows
1. What causes earthquakes?
a. Sudden shifts in the earth’s rock
layers cause earthquakes
2. The focus, or epicenter, is where the
3. During an earthquake, the plates might:
a. Meet in a rubbing way (shoulder to
b. Spread away from each other
c. Meet in a pushing way (subduction)--
4. New plates can be created during an
earthquake (especially at mid-ocean
5. A seismograph is used to measure
a. The Richter scale is used
to give them a number.
b. People cannot feel earthquakes
between a 1-2 on the scale.
c. An earthquake that receives a
7-8 destroys buildings.
a. Shake and destroy land, homes,
b. Create land by creating
mountains and valleys
3 Different Types of Rocks
Scientists classify rocks in 3 main groups
based on how they were formed.
1. Igneous Rocks (Fact: Igneous means “fiery”)
a. How they form: When magma
reaches the surface, it becomes
b. This hot, molten rock cools and
hardens to form igneous rock.
c. Characteristics: Igneous rocks
vary in size, shape, color, and texture.
Examples: basalt, pumice, obsidian
2. Sedimentary Rocks
a. Form in water from “sediment”, which is
grains and bits of rock that were created by
erosion or weathering.
b. Fact: The sediment builds up over many
years and becomes cemented together to
form sedimentary rock.
c. Characteristics: These rocks are layered.
The layers tell the story about how the rock
was formed. They can also have fossils,
which tell a story, too!
d. Examples: sandstone, limestone, shale, and
3. Metamorphic Rocks (means “change”)
a. Formed from another rock by heat and
b. Usually form beneath the earth’s
crust (which means they often heat up and
become magma again—it’s a cycle—the Rock
c. Fact: Both igneous and sedimentary rocks
can change into metamorphic rocks.
d. Characteristics: These rocks are usually
harder than the rocks that they were at first.
e. They may have “bands” which look like
stripes or layers from different minerals
pressed together by the heat and pressure.
Weathering and Erosion
1. Physical (mechanical) weathering happens when
the earth’s crust is exposed to water, air, and
changes in temperature.
a. Rocks can wear away, making smaller rock
pieces, or sediments.
b. Freezing water expands, or takes up
more space and can cause rocks to
2. Chemical weathering happens when gases in
the air chemically react with other elements
a. Acid rain can dissolve limestone rocks.
a. Is the carrying away of
weathered rock by gravity, water,
wind, and ice
b. Erosion can wash away boulders
Examples: soil washed onto the
sidewalk, crumbling rocks on
buildings, holes in the road, cracked
sidewalks, plants/roots growing by
sidewalks, muddy streams
Examples of Erosion and
• Sea cliffs form when a rocky shore erodes at
approximately the same rate throughout an area.
This results in a steep walled structure. The cliff
moves landward as the waves attack its base.
Examples of Erosion and
• Slot Canyons caused by flash floods
Places on Earth
• Mt. Everest is the highest place on earth—
29,029 feet high
• The Mariana Trench is the lowest place on
earth--36,069 feet deep
• The Dead Sea is the lowest place on the
surface of the earth—1,388 feet below sea
• Vostok Research Station in Antartica--
• Hottest place on earth?