Thermal Dynamics of Subduction Zones

Subduction zones mark the interface where an oceanic plate plunges beneath an overriding plate, driving complex heat and mass transfer between the slab, mantle wedge and crust. Temperature gradients within these zones evolve through distinct phases—from infancy, when the slab heats rapidly, to a mature stage characterised by slower cooling and deeper dehydration. Heat is conducted from the slab into the mantle wedge, where small-scale convection and thermal buoyancy govern melt generation, volcanic arc placement and seismic coupling. Slab dehydration releases bound water into the overlying mantle, lowering melting temperatures and lubricating the plate interface. These processes influence the depth limits of megathrust earthquakes, the distribution of arc volcanoes and the long-term water cycle of the solid Earth. Recent advances in numerical and geophysical imaging techniques have refined our understanding of how slab age, convergence rate, interface rheology and three-dimensional flow patterns shape thermal structure, with implications for hazard assessment, resource exploration and global geochemical cycles.

Research from Nature Portfolio

Numerical simulations in subduction settings of Japan demonstrate that hydrothermal circulation near the outer-rise can be reactivated in old oceanic lithosphere but rapidly halts upon entering the trench, challenging previous models of heat-driven demagnetisation. Instead, pressure-controlled mineral transformations in the slab significantly alter its thermal profile and residual magnetisation after subduction. In southwest Japan, self-consistent geodynamic models reveal the spontaneous formation of a weak, hydrous layer at the slab interface. This “cold nose” decouples the forearc mantle from the slab, cools the overlying mantle wedge, migrates the volcanic front and facilitates deep transport of free water, thereby linking thermal structure to geochemical signatures and seismic tremor fields.

Thermal Dynamics of Subduction Zones publication trend

The graph below shows the total number of articles in thermal dynamics of subduction zones across all publications each year (not limited to Nature Index journals).

Technical terms

Slab: The subducting oceanic lithosphere that descends into the mantle.

Mantle wedge: The region of mantle material above the subducting slab and below the overriding plate.

Dehydration front: The zone within the slab where hydrous minerals break down, releasing water.

Isotherm: A line or surface connecting points of equal temperature within a thermal model.

Forearc: The area between the trench and the volcanic arc, often characterised by a cool “cold nose.”

Brittle–ductile transition: The depth or temperature at which rocks change from brittle failure to ductile flow.

References

1. Slab to back-arc to arc: Fluid and melt pathways through the mantle wedge beneath the Lesser Antilles. Science Advances (2023).
2. Pressure-driven processes explain the decreasing magnetization of the subducting oceanic crust in the Japan Trench. Communications Earth & Environment (2023).
3. Evolving Subduction Zone Thermal Structure Drives Extensive Forearc Mantle Wedge Hydration. AGU Advances (2024).
4. Understanding subduction infancy to mature subduction in Southwest Japan via the self-consistent formation of a weak slab interface. Scientific Reports (2023).
5. 3D thermal structural and dehydration modeling in the southern Chile subduction zone and its relationship to interplate earthquakes and the volcanic chain. Geoscience Letters (2024).
6. Slab Temperature Evolution Over the Lifetime of a Subduction Zone. Geochemistry Geophysics Geosystems (2021).
7. A systematic 2‐D investigation into the mantle wedge's transient flow regime and thermal structure: Complexities arising from a hydrated rheology and thermal buoyancy. Geochemistry Geophysics Geosystems (2014).
8. Mantle wedge temperatures and their potential relation to volcanic arc location. Earth and Planetary Science Letters (2018).
9. The mantle wedge's transient 3‐D flow regime and thermal structure. Geochemistry Geophysics Geosystems (2016).