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[1] We introduce and test an experimental approach to simulate elastoplastic megathrust earthquake cycles using an analogue model and apply it to study the seismotectonic evolution of subduction zones. The quasi-two-dimensional analogue model features rate-and state-dependent elastic-frictional plastic and viscoelastic material properties and is scaled for gravity, inertia, elasticity, friction, and viscosity. The experiments are monitored with a high-resolution strain analysis tool based on digital image correlation (particle imaging velocimetry, PIV), providing deformation time series comparable to seismologic, geodetic, and geologic observations. In order to separate elastic and nonelastic effects inherent the experimental deformation patterns, we integrate elastic dislocation modeling (EDM) into a hybrid approach: we use the analogue earthquake slip and interseismic locking distribution as EDM dislocation input and forward model the coseismic and interseismic elastic response. The residual, which remains when the EDM prediction is subtracted from the experimental deformation pattern, highlights the accumulation of permanent deformation in the model. The setup generates analogue earthquake sequences with realistic source mechanisms and elastic forearc response and recurrence patterns and reproduces principal earthquake scaling relations. By applying the model to an accretionary-type plate margin, we demonstrate how strain localization at the rupture peripheries may lead to a seismotectonically segmented forearc, including a tectonically stable shelf and coastal high (<20% plate convergence accommodated by internal shortening) overlying the area of large megathrust earthquake slip. Fifty to 75% of plate convergence is accommodated by internal shortening in the slope region where earthquake slip tapers out toward the trench. The inner forearc region remains undeformed and represents a basin.Citation: Rosenau, M., J. Lohrmann, and O. Oncken (2009), Shocks in a box: An analogue model of subduction earthquake cycles with application to seismotectonic forearc evolution,

: We report a direct comparison of scaled analogue experiments to test the reproducibility of model results among ten different experimental modelling laboratories. We present results for two experiments: a brittle thrust wedge experiment and a brittleviscous extension experiment. The experimental set-up, the model construction technique, the viscous material and the base and wall properties were prescribed. However, each laboratory used its own frictional analogue material and experimental apparatus. Comparison of results for the shortening experiment highlights large differences in model evolution that may have resulted from (1) differences in boundary conditions (indenter or basal-pull models), (2) differences in model widths, (3) location of observation (for example, sidewall versus centre of model), (4) material properties, (5) base and sidewall frictional properties, and (6) differences in set-up technique of individual experimenters. Six laboratories carried out the shortening experiment with a mobile wall. The overall evolution of their models is broadly similar, with the development of a thrust wedge characterized by forward thrust propagation and by back thrusting. However, significant variations are observed in spacing between thrusts, their dip angles, number of forward thrusts and back thrusts, and surface slopes. The structural evolution of the brittle-viscous extension experiments is similar to a high degree. Faulting initiates in the brittle layers above the viscous layer in