Question

At convergent boundaries, two tectonic plates move toward each other.

Answer 1

True. At convergent plate boundaries the plates move toward one another. What happens depends on the types of crust involved:

- Oceanic–continental convergence: the denser oceanic plate subducts beneath the lighter continental plate. Features include a deep ocean trench at the plate edge, a volcanic mountain chain on the continent (a continental volcanic arc), strong earthquakes along a dipping seismic zone (Wadati–Benioff zone). Example: the Nazca plate subducting beneath South America (the Andes).

- Oceanic–oceanic convergence: one oceanic plate subducts under the other, producing a trench and an island-arc volcano chain on the overriding plate. Example: the Mariana Trench and Mariana Islands.

- Continental–continental convergence: when two buoyant continental plates collide, little or no subduction occurs; crust is thickened and folded to form large mountain ranges and broad zones of crustal deformation. Example: the India–Eurasia collision forming the Himalaya.

Common consequences of convergent boundaries: deep and shallow earthquakes (including deep-focus quakes), volcanism (except in continental–continental collisions), mountain building, crustal metamorphism, and recycling of crustal material into the mantle.