Related words. 1  poke noun. 2  poke around phrasal verb. 3  poke fun (at) phrase.  a pig in a poke 1  phrase. poke a hole in something phrase.  poke/shove/stick your nose into something 1  phrase. poke about phrasal verb at poke around.  poke fun at phrase at make fun of.
Because the subduction zone (which is also the plate boundary) is generally an arc-shape, geologists named those volcanoes volcanic arcs. A volcanic arc built on continental crust is called a continental arc; when built on oceanic crust the volcanoes form an island arc. Volcanic arcs are made of an arc-shaped chain of volcanoes. 2  The position of which could be continental or mid-ocean. 3  While an island arc must be offshore and does not necessarily be volcanic (e.g. Hellenic arc).
Another example, forming the northern rim of the Ring of Fire, is the Aleutian trench shown here: The Pacific plate descends into the mantle at the site of the Aleutian trench. Subduction zone volcanism here has generated the Aleutian island chain of active volcanoes.Courtesy of NOAA.sland arc formed by oceanic-oceanic subduction Volcanic arc formed by oceanic-continental subduction. Island arc formed by oceanic-oceanic subduction. Volcanic arc formed by oceanic-continental subduction. The volcanoes produced by subduction zone volcanism are typically stratovolcanoes.