Motion

Slow Motion on Planet Earth

Chapter 1

Section 2

Tectonic Plates

• Pieces of Earth’s Crust • 12+ major plates

Pangaea

• “Super-Continent”– ~250 million years ago

Theory of Plate Tectonics

• Earth’s plates move slowly in different directions

• Divergent– Move away

• Convergent– Move into

• Transverse– Move along

How Fast Do Plates Move???

• Slow plates…– 1-2 mm’s per year

• Fast plates…– 5-6 cm’s per year

• About as fast as your finger nails grow

San Andreas Fault, CA

• L.A. is on the Pacific Plate– Moving NNW at 3 cm’s

per year

• San Francisco is on the N. American Plate– Moving SSE at 2 cm’s

per year

• Now…– 544 km apart

• In 10 million years– Side by side