Subduction zones are complex, evolving systems in which the downgoing plate, plate interface, mantle wedge, overriding plate and surrounding mantle interact across a wide range of spatial and temporal scales. These interactions govern plate motions and deformation, shape mountain belts and sedimentary basins, drive mantle flow and chemical recycling, and generate much of Earth’s seismicity and volcanism. Yet fundamental questions remain about how subduction initiates, how it is maintained, why its geometry and style vary, and how subduction zones reorganize or cease.

This session focuses on the dynamics of the complete subduction system, from the surface and plate boundary to the transition zone and lower mantle. We invite contributions addressing subduction initiation, propagation, maturation and termination; slab geometry, strength and deformation; plate-interface coupling, seismicity and slow slip; mantle-wedge and sub-slab flow; overriding-plate deformation and topographic response; trench migration and slab rollback; flat-slab and stagnant-slab behaviour; tearing, break-off and delamination; interactions with ridges, plateaus, seamounts and inherited lithospheric structure; and slab penetration into, or stagnation within, the deep mantle.

We also welcome studies examining how rheology, thermal structure, phase transitions, hydration and dehydration, fluids, melts and compositional heterogeneity influence subduction dynamics and their surface expression. Contributions may address present-day or ancient systems and may use geophysical, geological, geodetic, geochemical and petrological observations, laboratory experiments, analytical theory or numerical models.