Subduction zones host a broad spectrum of seismic and aseismic activity, from the largest earthquakes on Earth to slow-slip events (SSEs) and tectonic tremors. These processes occur along the shallow megathrust, within the subducting slab, and on faults within the overriding plate. Understanding how short-term deformation and earthquake-cycle processes interact with the long-term tectonic evolution of convergent margins remains challenging. Earthquake occurrence, rupture size, and slip behaviour are influenced by several interacting factors, including the thermal and mechanical states of the subducting and overriding plates, fault-zone friction and rheology, megathrust structure, stress interactions, and fluid transport.

We invite multidisciplinary contributions addressing the mechanics controlling seismicity and fault deformation in subduction-zone settings, focusing on, but not limited to, the following questions: (i) How do the multiscale architecture of the megathrust and interacting faults control the spatial and temporal distribution of seismicity? (ii) How do rheological properties, stress interactions, and fluid and volatile transport govern transitions between different slip modes? (iii) Which physical processes produce the observed spectrum of coseismic and postseismic deformation? (iv) How do short-term earthquake-cycle processes interact with long-term tectonic processes in the subducting and overriding plates?

We encourage interdisciplinary contributions based on seismological, geodetic, geological, and other geophysical observations, as well as numerical and analogue modelling. By bringing together this broad range of disciplines and approaches, the session aims to assess the state of the art, identify current challenges, and discuss the coupling among processes operating across spatial and temporal scales, ultimately contributing to improved seismic and tsunami hazard assessment.