Controls on tectonic accretion versus erosion in subduction zones: Implications for the origin and recycling of the continental crust

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…

• NS
  National Science Foundation
• DO
  Division of Ocean Sciences