The Popular Anime Island Arc Plate Boundary Characters. In all types of convergence the denser plate subducts and the less dense plate is either up thrust or folded or both upthrust and folded. Andesitic volcanism crustal thickening.
In a subduction zone one lithospheric crustal plate is forced downward under an upper plate. An island arc is built up from the surface of the overriding plate by the extrusion of basalts and andesites. Much more of the ibm arc system is submerged below sealevel the ibm arc system lies along the eastern margin of the philippine sea plate in the western pacific ocean.
The subduction process occurs at the boundaries of the oceanic tectonic plates when one plate sinks under the other right into the mantle.
An island arc is a curving series of volcanic islands that are created through the collision of tectonic plates in an ocean setting. In ocean ocean convergence a denser oceanic plate subducts below a less dense oceanic plate forming a trench along the boundary. When the downward moving slab reaches a depth of about 100 km 60 miles it gets sufficiently warm to drive off its most volatile components thereby stimulating partial melting of mantle in the plate above the subduction zone known as the mantle wedge. When two plates are moving away from each other we call this a divergent plate boundary.
