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PLATE TECTONICS
I. Continental Drift
II. Sea Floor Spreading
III. Plate boundaries
IV. Exotic Terrains (Micro-plate tectonics)
I. Continental Drift
1. Jigsaw puzzle effect (present continents fit together like a puzzle)
e.g. Africa and South America
2. Correlation of Rocks and fossils
a. Permian to Triassic
Rocks--Karoo Series
Oldest
Dwyka Tillite
Ecca Beds - fossil-plants-Glossopteris
Youngest
Beaufort Beds - animals-Reptiles- Mesosaurus
b. Appalachian Mts. similar to Atlas Mts. of NW Africa
c. North Appalachians correlate to Caledonian mts. of NW Europe
3. Evidences from glaciers-glacial striations
4. San Andreas Fault 300-400 of right lateral movement in the last 30 million years
e.g. offset of Murray Fracture zone
5. East African Rift Zone separating 1-2 inches/year
6. Mountain Ranges
Himalayas-collision of India with Asia
7. Red Sea
8. Isolation of Animals, e.g. duckbilled Platypus, spiny anteater
9. Migration of the green turtle.
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II. Sea Floor Spreading
1. Oceanic Mountain Ranges, Trenches, Fracture Zones (all sites of earthquake and volcanic activity
indicates movement)
a. Mid Atlantic Ridge
b. East Pacific Ridge
c. Mid Indian Ridge
d. fracture zones
e. trenches and subduction zones.
2. Central Rift Zone
3. Composition of Ocean Crust verses continent crust
Ocean crust (Lithosphere) =Basalt
Continental Crust = Granite
Granite is lighter and floats on top of Basalt
This implies different origins for Magmas that become Basalt
4. Magnetic declination and inclination.
a. Calculation of sea floor spreading rates.
CONVECTION MODEL
and Granite
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5. Age of Rocks and Sediments
6. Heat Flow
7. Age of Seamounts and Guyots
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8. Hot Spots (migrating)
a. Yellowstone
b. Mammoth
c. Hawaiian Islands