As a lithospheric slab is being subducted, the slab melts when the edges reach a depth which is sufficiently hot. Hot, remelted material from the subducting slab rises and leaks into the crust, forming a series of volcanoes. These volcanoes can make a chain of islands called an “island arc”.

The continental arc is formed at an active continental margin where two tectonic plates meet, and where one plate has continental crust and the other oceanic crust along the line of plate convergence, and a subduction zone develops.

A continental volcanic arc forms along the margin of a continent where oceanic crust subducts beneath continental crust. Typically they contain silicic and some basaltic volcanic rock as well as volcaniclastic rock (that is, clastic sedimentary rock derived from erosion of a volcanic source).

continental arcs form when oceanic crust subducts beneath continental crust on an adjacent plate, creating an arc-shaped mountain belt.

When two oceanic plates collide against each other, the older and therefore heavier of the two subducts beneath the other, initiating volcanic activity in a manner similar to that which occurs at an oceanic-continental convergent plate boundary and forming a volcanic island arc.

When two continental plates converge, they smash together and create mountains. The amazing Himalaya Mountains are the result of this type of convergent plate boundary.

« Back to Glossary Index. A chain of volcanic activity, typically in a curved pattern, rising from a subduction zone. The arc is on the overriding plate, typically a few hundred kilometers from the trench, but parallel to the trench.

Continent-Continent Convergence Another type of convergent plate boundary is when two continental plates collide. When two plates of continental crust collide, the material pushes upward. This forms a high mountain range. The remnants of subducted oceanic crust remain beneath the continental convergence zone.

In Continent-Ocean (C-O) convergence, the continental volcanic arc formed along the continental plate margin is compressed and is uplifted by the colliding oceanic plate giving rise to fold mountains along the continental plate margin.

Vocabulary Language: English ▼ Term Definition continental arc Line of volcanoes on a continental plate convergent plate boundary Location where two lithospheric plates c island arc Line of volcanoes on an oceanic plate; t subduction Sinking of one lithospheric plate beneat

The continental arc is formed at an active continental margin where two tectonic plates meet, and where one plate has continental crust and the other oceanic crust along the line of plate convergence, and a subduction zone develops.

The denser plate subducts into the asthenosphere below the convergence zone and forms a trench at the surface. This region below the convergence zone is called the zone of subduction. In the zone of subduction, due to high temperature and pressure, the rocks undergo metamorphosis and the sediments in the oceanic plate melt to form magma.