Controls on tectonic accretion versus erosion in subduction zones : implications for the origin and recycling of the continental crust
MetadataShow full item record
Documenting the mass flux through convergent plate margins is important to the understanding of petrogenesis in arc settings and to the origin of the continental crust, since subduction zones are the only major routes by which material extracted from the mantle can be returned to great depths within the Earth. Despite their significance, there has been a tendency to view subduction zones as areas of net crustal growth. Convergent plate margins are divided into those showing long-term landward retreat of the trench and those dominated by accretion of sediments from the subducting plate. Tectonic erosion is favored in regions where convergence rates exceed 6 ± 0.1 cm yr−1 and where the sedimentary cover is <1 km. Accretion preferentially occurs in regions of slow convergence (<7.6 cm yr−1) and/or trench sediment thicknesses >1 km. Large volumes of continental crust are subducted at both erosive and accretionary margins. Average magmatic productivity of arcs must exceed 90 km3 m.y.−1 if the volume of the continental crust is to be maintained. Convergence rate rather than height of the melting column under the arc appears to be the primary control on long-term melt production. Oceanic arcs will not be stable if crustal thicknesses exceed 36 km or trench retreat rates are >6 km m.y.−1. Continental arcs undergoing erosion are major sinks of continental crust. This loss requires that oceanic arcs be accreted to the continental margins if the net volume of crust is to be maintained.
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Reviews of Geophysics 42 (2004): RG2001, doi:10.1029/2003RG000127.
Suggested CitationArticle: Clift, Peter D., Vannucchi, Paola, "Controls on tectonic accretion versus erosion in subduction zones : implications for the origin and recycling of the continental crust", Reviews of Geophysics 42 (2004): RG2001, DOI:10.1029/2003RG000127, https://hdl.handle.net/1912/3466
Showing items related by title, author, creator and subject.
Billen, Magali I.; Hirth, Greg (American Geophysical Union, 2007-08-28)Several models have been proposed to relate slab geometry to parameters such as plate velocity or plate age. However, studies on the observed relationships between slab geometry and a wide range of subduction parameters ...
Post-seismic viscoelastic deformation and stress transfer after the 1960 M9.5 Valdivia, Chile earthquake : effects on the 2010 M8.8 Maule, Chile earthquake Ding, Min; Lin, Jian (Oxford University Press, 2014-03-04)After the 1960 M9.5 Valdivia, Chile earthquake, three types of geodetic observations were made during four time periods at nearby locations. These post-seismic observations were previously explained by post-seismic afterslip ...
Seismic reflection imaging of the Juan de Fuca plate from ridge to trench : new constraints on the distribution of faulting and evolution of the crust prior to subduction Han, Shuoshuo; Carbotte, Suzanne M.; Canales, J. Pablo; Nedimovic, Mladen R.; Carton, Helene; Gibson, James C.; Horning, Gregory W. (John Wiley & Sons, 2016-03-21)We present prestack time-migrated multichannel seismic images along two cross-plate transects from the Juan de Fuca (JdF) Ridge to the Cascadia deformation front (DF) offshore Oregon and Washington from which we characterize ...