A. Part of the Earth that consists of several large and several small tectonic plates.

B. Movement of a fluid due to temperature difference.

C. Supports the Theory of Plate Tectonics.

D. Pulling the edge of some plates towards the center of the Earth.

E. A theory that states the Earth’s surface consists of large moving plates.

1. Plate Tectonics

2. Gravity

3. Lithosphere

4. Sea Floor Spreading

5. Convection Current

E

D

A

C

B

ReviewReviewPlate TectonicsDeep sea trenchesMid oceanic ridgesSea floor spreading

EarthquakesEarthquakes

A shaking of the earth’s crust due to a release of energy

OccurrencesOccurrences More than 3 million occur each

year About 8,000 per day, or 1

every 11 seconds Most are extremely weak There are three major

earthquake zones:

1. The Ring of Fire1. The Ring of Fire

2. Mid Ocean Ridges2. Mid Ocean Ridges

3. Eurasian – Melanesian Mountain Belt

Major Earthquake ZonesMajor Earthquake Zones

Most earthquakes occur along the edges of the earth’s lithospheric plate boundaries

BoundariesBoundaries

Divergent: Two plates are moving away from each other

Sea floor spreading

BoundariesBoundariesConvergent: Two plates are colliding

BoundariesBoundariesSubducting:On plate is forced under another

This is a type of

convergent boundary!

Subduction

zone

Pacific Plate

South America

Andes Mountains

BoundariesBoundariesTransform boundary:Sliding by one anotherNot creating or destroying land