Title: The Geosphere
1The Geosphere
2Changes occur on the Earth constantly
- Molten rock flows from volcanoes
- Hurricanes batter beaches and change coastline
- Earthquakes shake the ground
3The Earth is a system that consists of air,
water, rock and living things
- All of the parts interact with each other
4Scientists use special terms to describe the
different parts of the Earth
- Geosphere consists of all the rock, soils and
sediments on the Earth - Atmosphere consists of the air that surrounds
the Earth - Hydrosphere consists of all water, fresh or
saltwater - Biosphere all living things on the planet
5Most of the geosphere is located in the Earths
interior
- The average diameter of the Earth is 12,756km
6Discovering the Earths Interior
7The earth is like an onion
8The information we have concerning the interior
of the Earth comes to us from studying seismic
waves
- Seismic waves travel through different material
at different rates. When seismic waves change
direction or speed, it means they have moved
through different layers
9Scientists divide the Earth into three layers
based on composition
- Crust the thinnest layer of the Earth (5-20km
thick) made entirely of light elements - Mantle makes up 64 of the earths mass,
(2900km thick) made of rocks of medium density - Core has a radius of 3400km and composed of the
densest elements
10The Earth can also be divided into 5 layers based
on physical properties
- Lithosphere
- Asthenosphere
- Mesosphere (mantle)
- Outer core
- Inner core
11The lithosphere is the Earths outer layer
- It contains the crust and uppermost part of the
mantle and is divided into moving sections called
Tectonic Plates
12The asthenosphere is the layer beneath the
lithosphere
- The asthenosphere is the plastic solid layer of
the Earth that the plates move on top of
13The mesosphere consists of the lower mantle
between the asthenosphere and outer core
- The mesosphere contains molten rock which is
called magma
14The outer core is 2200km thick and made of nickel
and iron
- The outer core is mostly liquid
15The inner core is a solid sphere of iron, nickel
and cobalt (radioactive)
- The temperature of the inner core is thought to
be between 4000 and 5000 degrees Celsius
16Scientists believe that cobalt in the core decays
producing heat
- The heat from the core produces energy that makes
the magma move producing earthquakes, volcanoes
and plate movement