It is an area of tectonic plate collision where the more dense plate subducts, or follows a path underneath, the less dense plate.
Subduction zones and earthquakes. Subduction zones are plate tectonic boundaries where two plates converge, and one plate is thrust beneath the other. This process results in geohazards, such as earthquakes and volcanoes. Subduction zone volcanism occurs where two plates are converging on one another. One plate containing oceanic lithosphere descends beneath the adjacent plate, thus consuming the oceanic lithosphere into the earth's mantle. This on-going process is called subduction.  Stable subduction zones involve the oceanic lithosphere of one plate sliding beneath the continental lithosphere or oceanic lithosphere of another plate due to the higher density of the oceanic lithosphere. That is, the subducted lithosphere is always oceanic while the over-riding lithosphere may or may not be oceanic. 1 Subduction Zone Physics: Sinking of the oceanic lithosphere (sediments + crust + mantle), by contrast of density between the cold and old lithosphere and the hot asthenospheric mantle wedge, is the strongest force (but not the only one) needed to drive plate motion and is the dominant mode of mantle convection. Rockhound. A subduction zone is an area of tectonic plate collision where the more dense plate subducts, or follows a path underneath, the less dense plate. A subduction zone is the place where oceanic plate margin is being pushed under a continental plate or a less dense oceanic plate. Subduction Zones. Where two tectonic plates converge, if one or both of the plates is oceanic lithosphere, a subduction zone will form. An oceanic plate will sink back into the mantle. Remember, oceanic plates are formed from mantle material at midocean ridg Subduction zones are convergent boundaries where at least one of the tectonic plates is an oceanic crust. The new oceanic crust that forms in spreading centers is recycled in these zones. Subducting oceanic plate. The oceanic crust melts as it descends into the lithosphere and upper mantle.  In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate and sinks into the mantle as the plates converge. Regions where this process occurs are known as subduction zones. 1 Subduction Zone Physics: Sinking of the oceanic lithosphere (sediments + crust + mantle), by contrast of density between the cold and old lithosphere and the hot asthenospheric mantle wedge, is the strongest force (but not the only one) needed to drive plate motion and is the dominant mode of mantle convection. 10 hilariously insightful foreign words. A subduction zone is a convergent boundary where two tectonic plates collide. Plates are large, dense masses in the crust of the Earth, the lithosphere, that float on top of liquefied rock in the asthenosphere. They are constantly shifting and moving, so when they subduct, one pushes beneath the other. When an oceanic plate encounters a continental plate, the oceanic plate plunges beneath the other plate. Subduction zones are at high risk for earthquakes. Ocean trenches are most often located parallel to volcanic islands, at the boundary of a subduction zone. A subduction zone is the biggest crash scene on Earth. These boundaries mark the collision between two of the planet's tectonic plates. The plates are pieces of crust that slowly move across the planet's surface over millions of years. Where two tectonic plates meet at a subduction zone, one bends and slides underneath the other, curving down into the mantle. (The mantle is the hotter layer under the crust.). Tectonic plates can transport both continental crust and oceanic crust, or they may be made of only one kind of crust. Oceanic crust is denser than continental crust. At a subduction zone, the oceanic crust usually sinks into the mantle beneath lighter continental crust
http://www.ldeo.columbia.edu/~djs/aleut/info_for_public.html http://www.geology.sdsu.edu/how_volcanoes_work/subducvolc_page.html https://en.wikipedia.org/wiki/Subduction http://www.answers.com/Q/What_is_a_subduction_zone http://www.columbia.edu/~vjd1/subd_zone_basic.htm http://www.kids-fun-science.com/subduction-zones.html https://en.wikipedia.org/wiki/Subduction http://www.wisegeek.org/what-is-a-subduction-zone.htm http://www.livescience.com/43220-subduction-zone-definition.html
what is a subduction zone