Editing Subduction (section)

==Importance==
Subduction zones are important for several reasons:
* Subduction zone physics: Sinking of the oceanic [[lithosphere]] (sediments, crust, mantle), by the 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]].{{Citation needed|date=January 2023}}
* Subduction zone chemistry: The subducted sediments and crust dehydrate and release water-rich ([[aqueous]]) [[fluids]] into the overlying mantle, causing mantle melting and [[fractionation]] of elements between the surface and deep mantle reservoirs, producing island arcs and [[continental crust]]. Hot fluids in subduction zones also alter the mineral compositions of the subducting sediments and potentially the habitability of the sediments for microorganisms.<ref>{{Cite journal|last1=Tsang|first1=Man-Yin|last2=Bowden|first2=Stephen A.|last3=Wang|first3=Zhibin|last4=Mohammed|first4=Abdalla|last5=Tonai|first5=Satoshi|last6=Muirhead|first6=David|last7=Yang|first7=Kiho|last8=Yamamoto|first8=Yuzuru|last9=Kamiya|first9=Nana|last10=Okutsu|first10=Natsumi|last11=Hirose|first11=Takehiro|date=2020-02-01|title=Hot fluids, burial metamorphism and thermal histories in the underthrust sediments at IODP 370 site C0023, Nankai Accretionary Complex|journal=Marine and Petroleum Geology|volume=112|pages=104080|doi=10.1016/j.marpetgeo.2019.104080|bibcode=2020MarPG.11204080T |issn=0264-8172|doi-access=free|hdl=2164/13157|hdl-access=free}}</ref>
* Subduction zones drag down subducted oceanic sediments, oceanic crust, and mantle lithosphere that interact with the hot asthenospheric [[mantle (geology)|mantle]] from the over-riding plate to produce [[calc-alkaline]] series melts, ore deposits, and continental crust.
* Subduction zones pose significant threats to lives, property, economic vitality, cultural and natural resources, and quality of life. The tremendous magnitudes of earthquakes and volcanic eruptions can also have knock-on effects with global impact.<ref>{{cite web|url=https://www.usgs.gov/news/usgs-publishes-a-new-blueprint-can-help-make-subduction-zone-areas-more-resilient|title=USGS publishes a new blueprint that can help make subduction zone areas more resilient|publisher=United States Geological Survey|language=en|access-date=2017-06-21}}</ref>

Subduction zones have also been considered as possible [[Nuclear waste#Geologic disposal|disposal sites for nuclear waste]] in which the action of subduction itself would carry the material into the planetary [[Mantle (geology)|mantle]], safely away from any possible influence on humanity or the surface environment. However, that method of disposal is currently banned by international agreement.<ref name="isbn0-387-95560-7">{{cite book |author=Hafemeister, David W. |title=Physics of societal issues: calculations on national security, environment, and energy |publisher=Springer Science & Business Media|location=Berlin |year=2007 |page= 187|isbn=978-0-387-95560-5|url=https://books.google.com/books?id=LT4MSqv9QUIC&pg=PA187}}</ref><ref name="isbn0-7546-7133-X">{{cite book |author1=Kingsley, Marvin G. |author2=Rogers, Kenneth H. |title=Calculated risks: highly radioactive waste and homeland security |publisher=Ashgate |location=Aldershot, Hants, England |year=2007 |pages= 75–76|isbn=978-0-7546-7133-6 |url=https://books.google.com/books?id=bOP4-BpYXrEC&pg=PA75}}</ref><ref>{{cite web |url= http://www.law.berkeley.edu/centers/ilr/ona/pages/dumping2.htm |title= Dumping and Loss overview |work=Oceans in the Nuclear Age |access-date=18 September 2010 |archive-url=https://web.archive.org/web/20110605190619/http://www.law.berkeley.edu/centers/ilr/ona/pages/dumping2.htm |archive-date=June 5, 2011}}</ref><ref>{{cite web |title = Storage and Disposal Options. World Nuclear Organization (date unknown) |url = http://www.world-nuclear.org/info/inf04ap2.html |access-date=February 8, 2012 |archive-url=https://web.archive.org/web/20110719062404/http://www.world-nuclear.org/info/inf04ap2.html |archive-date=July 19, 2011}}</ref> Furthermore, plate subduction zones are associated with very large [[megathrust earthquake]]s, making the effects of using any specific site for disposal unpredictable and possibly adverse to the safety of long-term disposal.<ref name="isbn0-7546-7133-X"/>