Download Outer Core

Chapter 15, Section 1: Inside the Earth
What we are going to learn:
1. Identify the layers of the Earth by
their chemical composition.
2. Identify the layers of the Earth by
their physical properties.
3. Describe a tectonic plate.
4. Explain how scientists know about
the structure of Earth’s interior.
Three Layers of the Earth
The Crust is the outermost layer. 5- 100
km thick but is the thinnest layer.
 The Mantle is the layer between the
crust and the core. This is where
magma is found.
 The Core is the center part of the Earth
and is made of two parts, inner core and
outer core.

Outer Part of the Earth
The Crust is where we live.
 Next is the Lithosphere. Made from the
crust and the hard outer part of the
mantle.
 Next is the Asthenosphere. This is the
soft layer of the mantle where the
lithosphere “floats”.

Middle Earth
The Mesophere is the strong lower part
of the mantle between the
asthensophere and the core.
 The Outer Core is the outer part of the
core and is liquid.
 The Inner Core is the most center part of
the Earth and is made from solid iron.

How do we know for sure what’s
under us???
How can we know what each part is
made from if we haven’t been there?
 Scientists use vibrations called Seismic
Waves created during earthquakes to
determine thickness and composition.
 Waves move through solid and liquid
material at different speeds.

Tectonic Plates
The lithosphere is divided into puzzle
like pieces called Tectonic Plates.
 On the edge of these plates we get
mountains, earthquakes, volcanoes, and
sea floor spreading.

Convergent Boundaries
A Convergent Boundary is formed when
two plates collide with one another.
 This can be two contiential plates, two
ocean plates, or one contiential plate
with an ocean plate.

Divergent and Transform Boundaries
A Divergent Boundary is where two
tectonic plates are moving away from
one another.
 A Transform Boundary is where two
plates are sliding horizontally or beside
one another.

Sea Floor Spreading
At divergent boundaries in the ocean
magma is pushed up and new ocean
crust is formed pushing the old crust
outward.
 This process is constantly making new
ocean crust.

Deforming the Earth’s Crust
Deformation – when the shape of a rock
changes due to stress.
 Tension stress- pulling apart.
 Compression stress- pushing together.

Folding Rocks
Folding – the bending of rock layers due
to stress.
 Types of folds….

Faults in Rocks
Fault – is a break in a body of rock
where one side moves against the other
side.
 Types of faults…

Mountain Building
Folding and faulting can build mountains
 Types of mountains…
Folded Mountains

Mountain Building

Fault- Block Mountains
Mountain Building

Volcanic Mountains
Uplift

Uplift – the rising of regions of the
Earth’s crust to higher elevations.
Subsidence

Subsidence – the sinking of regions of
the Earth’s crust to lower elevations.