earth journey to the center of the earth. earths layers earth’s layers formed as a result of the...
TRANSCRIPT
EarthEarth
Journey to the Center of the Earth
Journey to the Center of the Earth
Earths LayersEarths Layers
• Earth’s layers formed as a result of the denser, heavier minerals being pulled in more by gravity.
• Earth’s layers formed as a result of the denser, heavier minerals being pulled in more by gravity.
Facts about the layersFacts about the layers
• Inner core– Solid iron and nickel
• Outer core– Liquid iron and nickel
• Mantle– Minerals that are in constant motion
• Crust– Top layer of the earth
• Inner core– Solid iron and nickel
• Outer core– Liquid iron and nickel
• Mantle– Minerals that are in constant motion
• Crust– Top layer of the earth
Structure of the EarthStructure of the Earth
• The Earth is made up of 3 main layers:– Core– Mantle– Crust
• The Earth is made up of 3 main layers:– Core– Mantle– Crust
Inner core
Outer core
Mantle
Crust Ms. Nikki
So what IS the Lithosphere?
So what IS the Lithosphere?
• The lithosphere is made up of the crust and small layer of the upper mantle that together form large chunks or plates that move gradually because they ride on hotter mantle. These plates make up the surface of the Earth.
• http://video.google.com/videoplay?docid=4835712194315869074#
• The lithosphere is made up of the crust and small layer of the upper mantle that together form large chunks or plates that move gradually because they ride on hotter mantle. These plates make up the surface of the Earth.
• http://video.google.com/videoplay?docid=4835712194315869074#
Tectonic PlatesTectonic Plates
How is the Earth like a broken cookie?
How is the Earth like a broken cookie?
• If you look at a map of the world, you may notice that some of the continents could fit together like pieces of a puzzle.
• If you look at a map of the world, you may notice that some of the continents could fit together like pieces of a puzzle.
World PlatesWorld Plates
Continents of the PastContinents of the Past• “Pangaea” : exists ~ 225 million years
ago– Supercontinent: the only continent on Earth
• Division of Pangaea ~ 135 million years ago– Into “Laurasia” (N. Hem)
• Included modern North America & Eurasia
– And “Gondwana” (S. Hem)• Included modern South America, Africa,
Antarctica, Australia, Madagascar, India and New Zealand
• “Pangaea” : exists ~ 225 million years ago– Supercontinent: the only continent on Earth
• Division of Pangaea ~ 135 million years ago– Into “Laurasia” (N. Hem)
• Included modern North America & Eurasia
– And “Gondwana” (S. Hem)• Included modern South America, Africa,
Antarctica, Australia, Madagascar, India and New Zealand
250 Million Years Ago250 Million Years Ago
200 Million Years Ago200 Million Years Ago
135 Million Years AgoJurassic Period
135 Million Years AgoJurassic Period
65 Million Years Ago65 Million Years Ago
Present DayPresent Day
In 250 Million YearsIn 250 Million Years
• http://www.infocobuild.com/books-and-films/nature/life-earth/episode-09.html
• http://www.infocobuild.com/books-and-films/nature/life-earth/episode-09.html
How and Why do Earth Plates
move?
How and Why do Earth Plates
move?
What is a convection current?
What is a convection current?
• A convection current is a circular flow due to molecules heating, moving faster, and becoming less dense-so they weigh less and rise.
• When they cool, they move slower and closer together-so they weigh more per space and sink.
• A convection current is a circular flow due to molecules heating, moving faster, and becoming less dense-so they weigh less and rise.
• When they cool, they move slower and closer together-so they weigh more per space and sink.
1. Molecules heat and become less dense
Facts about the layersFacts about the layers
• Crust– Outer layer– 5-100 km thick– 2 types of crust
• Oceanic (very dense, made of basalt)• Continental (less dense, made of granite)
• Crust– Outer layer– 5-100 km thick– 2 types of crust
• Oceanic (very dense, made of basalt)• Continental (less dense, made of granite)
Plate MovementPlate Movement
• “Plates” of lithosphere are moved around by the underlying hot mantle convection cells
• “Plates” of lithosphere are moved around by the underlying hot mantle convection cells
• Divergent
• Convergent
• Transform
• Divergent
• Convergent
• Transform
Three types of plate boundary
• Spreading ridges– As plates move apart new material is
erupted to fill the gap
• Spreading ridges– As plates move apart new material is
erupted to fill the gap
Divergent Boundaries
What happens when plates move toward each other?
What happens when plates move toward each other?
• This is called a Convergent boundary– The continental plates push up and
make mountains OR
• This is called a Convergent boundary– The continental plates push up and
make mountains OR
Plate BoundariesPlate Boundaries
• It’s called Subduction– When one plate (oceanic) dives under
the other (continental).
• It’s called Subduction– When one plate (oceanic) dives under
the other (continental).
SubductionSubduction
Plate BoundariesPlate Boundaries
• Transform boundary– Happens when 2 plates besides each
other move in opposite directions
• Transform boundary– Happens when 2 plates besides each
other move in opposite directions
Age of Oceanic Crust
Courtesy of www.ngdc.noaa.gov
