Download Changes Within the Earth

CHANGES WITHIN THE
EARTH
SECTION 2
IN THIS SECTION
• Earth’s Physical Characteristics
• Earth’s Physical Processes
• Understanding the Past
EARTH’S PHYSICAL CHARACTERISTICS
• Earth is made of 3 layers:
• Core- made of inner and outer layer
• Mantle- appox. 1800 miles thick
• Crust- between 5-22 miles thick
• Land, Wind, Air
• 4 spheres- litho, hydro, bio, atmos
• Continents- 7 (North America, South America, Asia, Europe, Africa, Australia,
Antartica)
EARTH’S PHYSICAL PROCESSES
• Volcanoes
• Form when magma breaks through the earth’s crust. Once to the surface it is
called lava.
• Violent eruption can have lasting impacts on the physical makeup of the
mountain and land surrounding it.
• Crust Movements
• Earth’s surface rock are fragile and can cause breakage in crust.
UNDERSTANDING THE PAST
• Scientist Alfred Wegener created the theory of “Pangaea” started 180 million
years ago. 1 land mass breaks off into the 7 current continents.
• Scientists developed the theory of plate tectonics. These are plates of the
earth’s crust that are constantly moving at a slow pace and creating pressure
on each other.
• Plate movements against each other once they collide will create friction.
This is what causes earthquakes and volcanoes to build magma in their
chambers.
• Earthquakes along these fault lines (plates) can cause serious damage.
Quakes on the ocean floor can cause tsunamies.