Transcript Earth`s Interior

EARTH’S INTERIOR
STUDYING BELOW EARTH’S SURFACE
The extreme conditions of Earth’s interior make
it very hard to study the inside of Earth.
 We must..

Study rock samples from inside Earth.
 Study seismic waves from earthquakes and how they
travel through different parts of Earth.


Seismic wave-a wave of energy that travels
through Earth after an earthquake.
DIGGING DEEP…
The deeper in Earth you get, the hotter the
temperature becomes.
 Pressure also increases greatly the deeper you
get.



Pressure is the amount of force on an area.
Density also increases the deeper you get, due to
the pressure.
EARTH’S COMPOSITIONAL LAYERS

Earth’s compositional layers are determined by
density differences.
CRUST

The outermost layer of solid rock including dry
land and the ocean floor.
Thickest under mountains, thinnest in the oceans.
 Oceanic crust-darker in color and made of basalt.
 Continental (land) crust-lighter in color and made of
granite.

MANTEL
Made up of rock that is very hot, but solid. (3,000
kilometers thick).
 The rock in the mantel is soft and flows slowly
but is still considered solid. (if you kicked the
mantel it would hurt your foot).
 Convection-the movement of rock because of
differences in density due to temperature.


Hotter rock rises, colder rock sinks.
CORE
Center of Earth
 Made of iron and nickel

PHYSICAL LAYERS

Based on whether the layer is solid or liquid.
LITHOSPHERE
Includes the crust and uppermost mantel.
 Stiff and rigid.
 Divided into tectonic plates.

ASTHENOSPHERE
Soft layer beneath the lithosphere which is more
flexible and can bend.
 Tectonic plates float on asthenosphere.

MESOSPHERE
Strong, lower part of the mantel.
 Denser than the asthenosphere and therefore
more solid.

OUTER CORE

Liquid layer that surrounds the inner core.
INNER CORE
Dense, solid metal.
 High pressure causes the metal to be solid.

EARTH’S MAGNETIC FIELD
Movements in Earth’s liquid core create a
magnetic field.
 Planet Earth acts as a giant magnet.
