Plate Tectonics and Earth History
Breakup and Assembly of Pangaea
Locating the Continents
• Since 200 m.y. ago: Magnetic Stripes
• In Pangaea: Fit of Edges
• Before Pangaea
– Fossil Assemblages
– Collision History
– Climate Indicators
– Paleomagnetism
Magnetic Dip
• The earth’s magnetic field has both a
horizontal and a vertical direction
Locating the Ancient Continents
• Paleomagnetism gives paleolatitudes
accurate to about 10 degrees
• There is no way of determining
paleolongitude
• The further back we go, the more pieces
are unaccounted for
Assembly of Pangaea
Rodinia
Closure of the Tethys
Pangaea,
220 m.y.
80 m.y.
The Mediterranean, 20 m.y.
The Mediterranean, 15 m.y.
The Mediterranean, 6 m.y.
Why Does the Middle East Have so Much Oil?
The Collision of India and Asia
Earthquakes in Asia
Plate Tectonics and Western
North America
Western U.S. and the Andes
How the West Was Stretched