Plate Tectonics Part 2 Types of Convergent Boundaries

Plate Tectonics – Part 2 Types of Convergent Boundaries PLATE COLLISIONS!!!!

Oceanic – Continental Convergence • 1. Collision!!! • 2. Continental Crust is less dense so Oceanic crust sinks (subducts) into the asthenosphere.

Oceanic – Continental Convergence • 3. Subducting Ocean Plate creates a Vshaped Trench. • 4. Oceanic Plate reaches the asthenosphere and melts.

Oceanic – Continental Convergence • 5. The melted magma begins to rise through the mantle and crust. • 6. It will rise to make a volcanic eruption. • 7. Lava cools forming a continental volcanic arc.

Oceanic – Continental Examples • Andes Volcanic Mountains • Cascades Mountain Range (Mt. St. Helens) (South America)

Oceanic – Oceanic Boundary • 1. Collision!!! • 2. The more dense ocean plate (older) subducts into the asthenosphere.

Oceanic – Oceanic Boundary • 3. Oceanic crust melts into magma. • 4. Magma becomes buoyant and rises. • 5. This eventually forms volcanic islands in the water.

Example of Oceanic-Oceanic Boundaries ALUETIAN ISLANDS

Example of Oceanic-Oceanic Boundaries Northern Mariana Islands

Continental – Continental Boundary • 1. Collision!!! • 2. Neither plate subducts because they are both low in density.

Continental – Continental Boundary • 3. Crust is compressed and deformed, forced upward forming a mountain range.

Example: Continental- Continental Convergence • Mt. Everest! (Himalayan Mts. )