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ABSTRACT. Most of the recent published geodetic models of the 2010 Maule, Chile mega-thrust earthquake (Mw=8.8) show a pronounced slip maximum of 15-20 m offshore Iloca (~35°S), indicating that co-seismic slip was largest north of the epicenter of the earthquake rupture area. A secondary slip maximum 8-10 m appears south of the epicenter west of the Arauco Peninsula. During the first weeks following the main shock and seaward of the main slip maximum, an outer rise seismic cluster of >450 events, mainly extensional, with magnitudes Mw=4-6 was formed. In contrast, the outer rise located seaward of the secondary slip maximum presents little seismicity. This observation suggests that outer rise seismicity following the Maule earthquake is strongly correlated with the heterogeneous coseismic slip distribution of the main megathrust event. In particular, the formation of the outer-rise seismic cluster in the north, which spatially correlates with the main maximum slip, is likely linked to strong extensional stresses transfered from the large slip of the subducting oceanic plate. In addition, high resolution bathymetric data reveals that bending-related faulting is more intense seaward of the main maximum slip, where well developed extensional faults strike parallel to the trench axis. Also published seismic constraints reveal reduced P-wave velocities in the uppermost mantle at the trench-outer rise region (7.5-7.8 km/s), which suggest serpentinization of the uppermost mantle. Seawater percolation up to mantle depths is likely driven by bending related-faulting at the outer rise. Water percolation into the upper mantle is expected to be more efficient during the co-seismic and early post-seismic periods of large megathrust earthquakes when intense extensional faulting of the oceanic lithosphere facilitates water infiltration seaward of the trench. RESUMEN. Sismicidad ʻouter rise' relacionada con el mega terremoto de Maule, Chile en el 2010 e hidratación de la litósfera oceánica subductante. La mayoría de los modelos geodésicos del terremoto de 2010 en la Región del Maule, Chile (Mw=8.8) muestran un pronunciado deslizamiento máximo de 15-20 m frente a las costas de Iloca (~35°S), indicando que el mayor deslizamiento cosísmico fue en la parte norte del área de ruptura. Un deslizamiento secundario, con un máximo de 8-10 m aparece al sur del epicentro, localizado al sur de la península de Arauco. Durante las semanas siguientes al evento principal y frente al área de máximo deslizamiento, se formó un enjambre sísmico de más de 450 eventos, con mecanismo de foco mayoritariamente extensional y de magnitudes Mw, oscilando entre los 4 y 6 grados. En contraste con ello, el área del ʻouter rise', ubicada frente a la zona sur de deslizamiento máximo, presenta baja sismicidad. Esta observación sugiere que la sismicidad ʻouter rise' posterior al evento principal del terremoto del Maule está fuertemente correlacionada con la distribución heterogénea de deslizamiento cosísmico. En particular, la formación del enjambre de sismicidad ...