A plate boundary is where the edges of two plates meet.A plate boundary is where the edges of two plates meet. There are 3 types of boundaries: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.Occur where plates move apart. Most divergent boundaries are found in the ocean.

In the ocean, divergent boundaries are also called spreading centers.In the ocean, divergent boundaries are also called spreading centers. Mid-ocean ridges mark the sites where the ocean floor is spreading apart.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.As the ridges continue to widen, a gap called a rift valley forms.

Occur where plates push together.Occur where plates push together. There are 3 types of convergent plate boundaries.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.