Editing Forearc (section)

{{short description|Region between an oceanic trench and associated volcanic arc}}
[[File:Cross-section of a subduction zone and back-arc basin.jpg|thumb|275x275px|Cross-section of a subduction zone and back-arc basin. The forearc is the region between the trench and the volcanic arc. ]]
A '''forearc''' is a region in a [[subduction zone]] between an [[oceanic trench]] and the associated [[volcanic arc]]. Forearc regions are present along [[convergent boundary|convergent margins]] and eponymously form 'in front of' the volcanic arcs that are characteristic of convergent plate margins. A [[back-arc region]] is the companion region behind the volcanic arc.

Many forearcs have an [[accretionary wedge]] which may form a topographic ridge known as an outer arc ridge that parallels the volcanic arc. A forearc basin between the accretionary wedge and the volcanic arc can accumulate thick deposits of sediment, sometimes referred to as an outer arc trough. Due to collisional stresses as one tectonic plate subducts under another, forearc regions are sources for powerful earthquakes.<ref name="Fuller et al. 2006">{{cite journal |last1=Fuller |first1=C. W |last2=Willet |first2=S.D. |last3=Brandon |first3=M.T. |title=Formation of forearc basins and their influence on subduction zone earthquakes |journal=Geology |pages=65–68 |year=2006 |volume=34 |issue=2 |doi=10.1130/g21828.1 |bibcode=2006Geo....34...65F}}</ref><ref name="Kearey et al. 2006">{{cite book |last1=Kearey |first1=Philip |last2=Klepeis |first2=A. Keith |last3=Fredrick |first3=Vine J. |title=Global Tectonics |year=2009 |publisher=J. Wiley |location=Singapore by Moarkono |isbn=978-1-4051-0777-8 |edition=3rd |pages=1–400}}</ref>