Plate Tectonics

Convergent Boundary

• when two plates come together
• Subduction - dense oceanic plate dives beneath lighter continental plate; ocean trench, volcano
• if two continental plates converge, resist subduction, leads to folding and faulting mountain

Divergent Boundary

• when plates move apart
• forms mid ocean ridges
• newest crust on earth
• sometimes called a rift
• ocean floor spreading
• Polarity
• stripes on both sides of the ridge
• reversed polarity

Transform Boundary

• when plates slide or twist past each other
• leads to earthquakes