Download Plate Boundaries Notes

• A plate boundary is where the
edges of two plates meet.
• There are 3 types of boundaries:
1. Divergent
2. Convergent
3. Transform
• Occur where plates move apart.
Most divergent boundaries are
found in the ocean.
• In the ocean, divergent boundaries
are also called spreading centers.
• Mid-ocean ridges mark the sites
where the ocean floor is spreading
apart.
• As the ridges continue to widen, a
gap called a rift valley forms.
• Occur where plates push together.
• There are 3 types of convergent
plate boundaries.
1. Continental-continental collision:
– Occurs where 2 plates carrying
continental crust (same density)
push together.
– If the plates keep moving, their
edges crumple and fold.
2. Oceanic-oceanic subduction:
–Occurs where one plate with
oceanic crust sinks, or subducts,
under another plate with oceanic
crust.
–Deep-ocean trenches and island
arcs form.
3. Oceanic-continental subduction:
–Occurs when ocean crust sinks
under continental crust.
–Deep-ocean trenches and coastal
mountains form.
• Occur where plates scrape past
each other in opposite directions.
• Occur where plates scrape past
each other in opposite directions.
• Occur where plates scrape past
each other in opposite directions.