plate tectonics environmental science. plate tectonics the earth inside out bathymetry and seafloor...
TRANSCRIPT
Plate TectonicsEnvironmental Science
Plate Tectonics
The Earth Inside OutBathymetry and Seafloor Mapping
The Theory of Continental DriftLab continental drift
Seafloor SpreadingLab seafloor spreading
Plate TectonicsLab plate tectonics
Earth’s Internal Layers
How do we classify the Earth’s internal layers?
How is the lithosphere different from the crust?
Layers of the Earth
Composition, Density and Temp.
Core: Nickel (Ni), Iron (Fe) and other heavy elements
Inner core and outer core same temperature however massive pressure and density keeps inner core solid
Mantle: mostly Silicon (Si) and Oxygen (O)Lower density than coreLower mantle is solid, upper mantle is “plasticy”
Lithosphere and Asthenosphere
Lithosphere and Asthenosphere
Lithosphere = Crust and upper part of upper mantle
Asthenosphere = lower part of upper mantle
Lithosphere “floats” on asthenosphere
Rock Cycle
What are the three types of rock? How does the rock cycle account for their formation?
Isostatic Equilibrium
How does Archimedes Principle relate to the structure of the Earth?
What is isostatic equilibrium?
What links some earthquakes with isostatic equilibrium? Where do such earthquakes occur?
Archimedes Principle
Archimedes Principle
Isostatic Equilibrium
IsostasyThe lithosphere floats
on the asthenosphere
The various portions of the Earth’s crust reach gravitational equilibrium
Due to variations in thickness and density, some crustal blocks ride higher than others
Isostatic Rebound
Isostatic Equilibrium is the balance between the weight of the lithosphere and the buoyant force of the asthenosphere
Isostatic Rebound is when compensation occurs from an increase or decrease of lithospheric weight…causing earthquakes along weak areas called - faults
Onto the Festivities!!!
Alfred Wegner and Continental Drift
What is Pangea and Panthalassa?
What is the theory of continental drift?
What evidence did Wegner use to support his theory?
Why didn’t scientists support his theory? What further evidence could have strengthened his theory?
Pangea
Panthalassa
Wegner’s Theory
Pangea: big supercontinent
Panthalassa – Ocean surrounding Pangea
Wegner theorized that because the less dense continents floated on the more dense matle, Pangea broke apart into separate pieces.
Theory of Continental Drift
The Evidence
Pieces fit together like a puzzle
Fossil Distribution
Accepted Theory? I Think Not!
Good evidence but no go for public acceptance.
Possibly because Alfred was a meteorologist not a geologist
To many gaps between continents
He disappeared on an expedition in 1930 in Greenland
Later on, plate tectonics theory described how the gaps between the continents were continental shelves
O.k. Let’s Check It Out
Pangea Lab!!!!
Oooooh Yeah Baby!