NS 1300 Emergence of Modern Science

Chapter #17Plate Tectonics

Plate Tectonic Theory

Continental Drift

Pangea

Biogeography

Magnetic Reversals

Earth’s Interior

Inner Core (solid)Outer Core (liquid)MantleMohoAthenosphere (plastic)Lithosphere (crust)

HydrosphereAtmosphere

Crust – Mantle Boundary

Crustal Plates

Types of Plate Boundaries

Divergent Plate Boundaries

Convergent Plate Boundaries

Transform Plate Boundaries

Divergent Plate Boundaries

Sea-Floor Spreading

Age of Ocean Floor

Magnetic Anomalies

Convergent Plate Boundaries

Subduction

Volcanic Arcs

Orogeny

Transform Boundaries

San Andreas Fault

Hot Spots

Oceanic Hot SpotsIsland Chains

Continental Hot Spots

Describing Plate Motion

Rotation Pole

Angular Momentum

Pangea

Geologic Maps

Quiz

1. T or F, the earth’s mantle is made of solid rock.

2. T or F, the mid-ocean ridge is a convergent boundary.

3. T or F, the Marianis trench is a divergent boundary.

4. T or F, the San Andreas fault is a transform boundary.

5. T or F, the Hawaiian Islands are the result of hot spot volcanism.

Test QuestionsThe earth is made of many layers: the solid inner core, liquid outer core, plastic mantle, and solid crust.

The earth’s crust is a thin solid layer of rock floating on the plastic mantle below it. The crust is broken up into many plates. Plates can have ocean crust, continental crust, or combinations of both.

Hot spots in the mantle form island chains as ocean crust moves above them.

The theory of plate tectonics is the unifying theory of geology. Evidence of plate tectonics includes magnetic reversals, the shape of the continents, and patterns of biogeography, volcanic activity, and hot spot island chains.

Ocean crust is denser than continental crust, so it sinks deeper in the mantle.

Where plates move apart as new crust forms is called a spreading center or rift zone. This can occur in the oceans or on land.

When plates with ocean crust run into plates with continental crust they are subducted.

When two plates with continental crust collide, mountains form through orogeny.

When plates with a combination of ocean and continental crust collide they slide against each other along transform faults.