Erratum: Geochemical evidence for enhanced fluid flux due to overlapping subducting plates

Abstract

Overlapping subduction of the Pacific and Philippines Sea plates leads to an enhanced fluid flux to the mantle source of arc volcanoes in central Japan. Spatial variability in the amount of fluid that each plate contributes is determined by the configuration of the subducting plates. Aqueous fluids released from subducting plates play an important role in magma generation in many arc settings1,2,3,4. However, different hypotheses have been proposed for the origin of these fluids, the extent to which they mix with the mantle wedge and spatial variations in their composition2,3,4, especially at complex settings involving more than one subducting plate. Central Japan is one such setting, where the Pacific and Philippine Sea plates subduct underneath the North American and Eurasian plates and cause extensive arc magmatism to the west and north of Tokyo. Here, we use geochemical data for rocks from 28 Quaternary volcanoes in central Japan to quantify the relative contribution of fluids originating from the two subducting plates and their spatial distribution. We find that the fluid originating from the Philippine Sea plate is chemically distinct and its flux is localized, as compared with the larger-scale flux from the Pacific plate. In the regions where these two plates overlap, the Philippine Sea plate does not seem to significantly inhibit fluid flow from the Pacific plate below; instead, this geometry leads to enhanced fluid flux. Regional variations in fluid flux and composition are controlled primarily by the geometry and configuration of the subducting plates.