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 V-shaped 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 Cascades Mountain Range (Mt. St. Helens) Andes Volcanic Mountains (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.)