Plate Tectonics

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Alfred Wegener:

- First proposed hypothesis, 1915

- published The Origin of Continents and Oceans.

- Wegener's Pangea redrawn om his book published in 1912

Continental drift hypothesis:

- Supercontinent called Pangea began breaking apart about 200 million years ago.

- Continents *drifted* to present positions

- Continents *broke* through the Ocean crust

Wegener's Continental Drift Hypothesis:

- Evidence used by Wegener.

Fit of South America and Africa

Fossils match across the Seas

Rock types nd structures match

Ancient climates.

Rejection of the Drift Hypothesis:

- Main objection to Wegener's proposal was inability provide a Mechanism.

Between the Northamerican plate and the cCaribbean plate

are The Motagua fault and The Polochic fault.

Theory of Plate Tectonics:

- More encompassing than continental drift

- Associated th Earth's rigid Outer shell

- Called the Lithosphere

- Consists of several plates:

Plates are moving slowly

Largest plate is the Pacific plate

Plates are mostly beneath the Ocean.

magma is liquified rock under the earth

Guatemala's land is divided by two plates

- The caribbean plate

- The Northamerican plate

Guatemala's ocean includes one plate:

- Cocos plate