Calvès G. auteur aut IRD Auguy C. auteur aut IRD de Lavaissière L. auteur aut IRD Brusset S. auteur aut IRD Calderon Y. auteur aut IRD Baby Patrice auteur aut IRD text journalArticle eng text/pdf born digital access New 3-D seismic data collected over 4870 km(2) in the 3 degrees 45S-12 degrees 30S Peruvian segment of the East Pacific subduction system image seafloor erosional surfaces that can be mapped across the fore-arc basins. Fore-arc basins experience various stresses, from their base where basal tectonic erosion acts to the seafloor which is influenced by aerial, shallow, and deep water currents driven by waves or thermohaline oceanic currents. Previously there has been little interest in stresses on the upper layer and there is a lack of documentation of unconformities and the erosive processes in certain bathymetric domains in fore-arc basins. We address this with the study of examples sourced from 3-D seismic reflection surveys of the seafloor offshore Peru. Unconformities occur in two distinctive bathymetric domains associated with the continental shelf and the upper slope of the margin. Identification and characterization of unconformity surfaces yield estimates of the amount of erosion at the modern seafloor that range from 18 to 100%. Regional physical oceanography allows us to calibrate potential candidates for these two distinctive domains. The first control on erosion is the dynamics of deep to intermediate oceanic currents related to the Humboldt-Peru Chile water masses, while the second is wave action in the shallower erosional surfaces. This study illustrates the unseen landscape of the fore-arc basins of South America and helps to highlight the importance of erosive surficial processes in subduction landscapes. specialized fore-arc basin seafloor 3-D seismic reflection seismic geomorphology discontinuities unconformities erosion Humboldt Peru-Chile current Peru PEROU PACIFIQUE HUMBOLDT COURANT 064 066 18 8 3062-3077 2017 1525-2027 https://www.documentation.ird.fr/hor/fdi:010071032 10.1002/2017gc007036 1525-2027 [F B010071032] https://www.documentation.ird.fr/hor/fdi:010071032 https://www.documentation.ird.fr/intranet/publi/2017/10/010071032.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2017-10-31 2023-07-11 fdi:010071032 fre