Transcript Earth`s Interior - Brighten Academy Middle School

Earth’s Interior
Essential Question:
How are the Earth’s layers divided?
Earth’s Interior Vocabulary
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Crust –
Mantle –
Lithosphere –
Athenosphere
Mesosphere
Outer core –
Inner core -
Who Studies the Earth’s Structure?
• Geology is the study of the solid Earth.
• Geologists study the forces that have
shaped the Earth throughout its long
history.
How Do Scientists Know What’s Inside
Earth?
• Because of the extreme conditions in the
Earth’s interior, geologists cannot explore
deep into the Earth.
• Instead they use seismic waves from
earthquakes to study how they travel
through the Earth.
• The speed of seismic waves and the paths
they take reveal how the planet is put
together.
• Geologists have found that the Earth’s
interior is made up of several layers.
So How Many Layers Are There?
• If you were to travel into the Earth, you
would find 3 main layers each with its own
conditions and materials.
– Crust
– Mantle
– Core
• The deeper into the Earth layers you
travel, the greater the temperatures and
pressure.
Layers Diagram
Earth’s Crust
• The crust is the outermost layer of the
Earth’s surface.
• The crust is composed of rocks,
mountains, soil and water.
• The crust is the thinnest layer of all of
Earth’s layers.
• There are 2 types of crust:
– Continental crust that forms the continents
made of less dense rocks like granite.
– Oceanic crust that is beneath the ocean and
made of dense rock like basalt
Diagram of Earth’s Crust
Earth’s Mantle
• Between 5 and 40 kilometers deep, a new layer
of hot rock is found called the mantle.
• This solid material upper layer of the mantle and
the crust form a rigid layer called the lithosphere
(100 km thick)
• Beneath the upper layer of the mantle is a softer,
pliable layer of hot rock called the athenosphere.
• The lithosphere “floats” very slowly on top of the
athenosphere.
• Beneath the athenosphere, is another 2900 km
of solid mantle material.
Diagram of Earth’s Mantle
Earth’s Core
• The center layer of the Earth is called the
core made of nickel and iron.
• The core consists of 2 parts:
– Outer core – the layer of molten metal that
surrounds the inner core.
– Inner core – the dense ball of solid metal due
to the extreme pressure there.
• The core makes up 1/3 of the Earth’s
mass, but only 15% of its volume.
• The whole core is a little bit smaller than
our moon.
Earth’s Core Diagram
Let’s Review
• What is the study of the solid Earth called?
• Scientist who study the forces that have formed
the Earth’s surface are called what?
• What 2 things increase the deeper within the
Earth’s layers one may go?
• How many layers does the Earth have?
• What are the 2 sublayers with the Earth’s
interior?
• What is the difference between the parts of the
core? Why?