'''Subduction polarity reversal''' is a geologic process in which two converging plates switch roles: The over-lying plate becomes the down-going plate, and vice versa. There are two basic units which make up a [[Subduction|subduction zone]]. This consists of an overriding plate and the subduction plate.<ref name=":142">{{Cite book|url=http://www.springer.com/gp/book/9783540885573|title=Arc-Continent Collision {{!}} Dennis Brown {{!}} Springer}}</ref> Two plates move towards each other due to [[Tectonics|tectonic forces]].<ref name=":142" /> The overriding plate will be on the top of subducting plate.<ref name=":142" /> This type of tectonic interaction is commonly found in many [[Plate tectonics|plate boundaries]].<ref name=":142" />
However, some Geologistsgeologists propose that the roles of the overriding plate and subducting plate do not remain the same infinitely.<ref name=":113">{{Cite journal|last=Chemenda|first=A. I.|last2=Yang|first2=R. -K.|last3=Stephan|first3=J. -F.|last4=Konstantinovskaya|first4=E. A.|last5=Ivanov|first5=G. M.|date=2001-04-10|title=New results from physical modelling of arc–continent collision in Taiwan: evolutionary model|url=http://www.sciencedirect.com/science/article/pii/S0040195100002730|journal=Tectonophysics|volume=333|issue=1–2|pages=159–178|doi=10.1016/S0040-1951(00)00273-0}}</ref> Their roles will swap, which means the plate originally subducting beneath will become the overriding plate.<ref name=":113" /> This phenomenon is called '''subduction switch''',<ref>Willett, S. D., & Beaumont, C. (1994). Subduction of Asian lithospheric mantle beneath Tibet inferred from models of continental collision. ''Nature'', ''369''(6482), 642–645.</ref> '''the flipping of subduction polarity'''<ref name=":132222">{{Cite journal|last=Teng|first=Louis S.|last2=Lee|first2=C. T.|last3=Tsai|first3=Y. B.|last4=Hsiao|first4=Li-Yuan|date=2000-02-01|title=Slab breakoff as a mechanism for flipping of subduction polarity in Taiwan|url=http://geology.gsapubs.org/content/28/2/155|journal=Geology|language=en|volume=28|issue=2|pages=155–158|doi=10.1130/0091-7613(2000)282.0.CO;2|issn=0091-7613}}</ref> or '''subduction polarity reversal'''.<ref name=":113" />
Examples of subduction systems with subduction polarity reversal are:
