Temperature Distribution in the Mantle under the Continental Limb of the Subduction Zone and in the Subducting Plate

摘要

Temperature distribution in the upper mantle under the continent and in the lower mantle was found. In the continental lithosphere the solution was obtained in the approximation of conductive heat transfer with internal heat sources in the continental crust. The temperature profiles over the thickness of the upper and lower mantle were obtained using the results of experimental and theoretical modeling of free convective heat transfer in a horizontal layer of a viscous fluid heated from below and cooled from above. The model of thermal and hydrodynamic structure of the subduction zone is presented, including a scheme of free-convective flows in the asthenospheric layer and layer C. The temperature profiles in the subducting lithospheric plate and in the continental limb of the subduction zone are presented. The heat flow due to friction at the boundary of the subducting plate and the continental limb has a significant effect on heat transfer and the formation of the temperature field in the subduction zone. The temperature level in the crustal layer of a subducting oceanic plate indicates the absence of melting in this layer.