What happens when oceanic plates collide?

Question

Leo Arens · Accepted Answer

The creation of volcanic chains, called island arcs.

Density is important here.

Oceanic plates are primarily basaltic in composition, meaning the rock that makes up the plate is mostly basalt (an extrusive igneous rock). Basalt is a fairly dense rock, but as it ages it gets colder, therefore it is more dense than the younger plates being formed at the mid-ocean rifts. This means the older plate subducts beneath the younger plate. The result is nearly identical to what happens when an oceanic plate converges with a continental plate. The only difference is that the uplifted arc occurs in the ocean, so it's termed an island arc.

Check out the Aleutian Peninsula of Alaska. It's very active.

Violet Adams · Answer

undefined When oceanic plates collide, the denser plate typically subducts beneath the less dense plate. This process forms a subduction zone, where the descending plate is forced into the Earth's mantle. As the oceanic plate sinks, it can cause melting in the mantle, leading to the formation of magma. This magma can then rise to the surface, creating volcanic activity. Additionally, the collision and subduction of oceanic plates can generate earthquakes due to the intense pressure and friction along the plate boundary. Over time, this collision can result in the formation of volcanic arcs and island chains.