Gailler A. auteur aut IRD Charvis Philippe auteur aut IRD Flueh E. R. auteur aut IRD text journalArticle eng text/pdf born digital access We describe the deep structure of the south Colombian-northern Ecuador convergent margin using travel time inversion of wide-angle seismic data recently collected offshore. The margin appears segmented into three contrasting zones. In the North Zone, affected by four great subduction earthquakes during the 20th century, normal oceanic crust subducts beneath the oceanic Cretaceous substratum of the margin underlined by seismic velocities as high as 6.0-6.5 km/s. In the Central Zone the subducting oceanic crust is over-thickened beneath the Carnegie Ridge. A steeper slope and a well-developed, high velocity, Cretaceous oceanic basement characterizes the margin wedge. This area coincides with a gap in significant subduction earthquake activity. In the South Zone, the subducting oceanic crust is normal. The fore-arc is characterized by large sedimentary basins suggesting significant subsidence. Velocities in the margin wedge are significantly lower and denote a different nature or a higher degree of fracturing. Even if the distance between the three profiles exceeds 150 km, the structural segmentation obtained along the Ecuadorian margin correlates well with the distribution of seismic activity and the neotectonic zonation. specialized wide angle seismic data traveltime tomography Ecuadorian margin subduction zone segmentation of active margin subduction earthquakes 066 260 3-4 444-464 2007 0012-821X https://www.documentation.ird.fr/hor/fdi:010040732 10.1016/j.epsl.2007.05.045 0012-821X [F B010040732] https://www.documentation.ird.fr/hor/fdi:010040732 https://www.documentation.ird.fr/intranet/publi/2007/10/010040732.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2007-11-06 2017-08-23 fdi:010040732 fre