Plate Techtonics

Question 1

What is Oceanography?

Answer 1

The application of all sciences to the phenomena of the ocean.

Question 2

What are the 4 fields of study in Oceanography?

Answer 2

• Geological
• Physical
• Chemical
• Biological

Question 3

What did magnetic anomalies prove?

Answer 3

Magnetic anomalies gave proof of seafloor spreading.

Question 4

One way tectonics can influence the ocean.

Answer 4

Influence the circulation of currents & tides.

Question 5

What affect does magnetism in the ocean crust have?

Answer 5

Periodically the magnetic field switches orientation.
Magnetic polarity is normal around the ridge crest but reversed in symmetrical patterns away from the center of the ridge.
The normal and reversed pattern continues along the sea floor.

Question 6

What are the two types of crust?

Answer 6

• Oceanic
  More dense, rich in iron & magnesium
• Continental crust
  Less dense, rich in silica & aluminum

Question 7

How far do plates move each year?

Answer 7

Plates move at an average of 2 - 12 cm per year.

Question 8

What is tectonics?

Answer 8

The study of the deformation of rocks that make up the Earth’s crust and the forces that produce such deformation.

Question 9

What rocks are affected by the magnetic field?

Answer 9

Nearly all igneous rocks contain magnetite, these rocks naturally align with the magnetic field.

Question 10

What is magnetite?

Answer 10

Naturally magnetic iron mineral found in most igneous rocks.