Lecture 6 - Plate Tectonics

Question 1

Alfred Wegner

Answer 1

• German Meteorologist and geophysicist
• Proposed “Continental Drift” in 1926

Question 2

Sea-floor Spreading

Answer 2

• Harry Hess (late 1950s)proposed sea-floor spreading hypothesis
• Continents move apart and collide

Question 3

Paleomagnetism

Answer 3

The study of the alignment of magnetic minerals in rock, specifically as it relates to the reversal of Earth’s magnetic poles; also the magnetic properties that rock requires during formation

Question 4

Marine Magnetic Anomalies

Answer 4

The difference between the expected strength of the Earth’s main dipole field at a certain location on the sea floor and the actual measured strength of the magnetic field at that location.

Question 5

Polarity Reversal

Answer 5

a time in geologic history when the south magnetic pole became the north magnetic pole and vice versa.

Question 6

Plate Tectonics Mechanism

Answer 6

• Mantle convection currents are likely responsible for tectonic movement
• Hot rocks in the Mantle act like a lava lamp

Question 7

The Earth’s Interior

Answer 7

Crust - Low density rock
Mantle - HIgh density rock
Outer Core - Liquid rock
Inner Core - Solid iron and nickel

Question 8

Types of Plate Boundaries

Answer 8

divergent, convergent, transform

Question 9

Convergent Boundary

Answer 9

A plate boundary where two plates move toward each other.