Louterbach M. auteur aut IRD Roddaz Martin auteur aut IRD Antoine P. O. auteur aut IRD Marivaux L. auteur aut IRD Adnet S. auteur aut IRD Bailleul J. auteur aut IRD Dantas E. auteur aut IRD Santos R. V. auteur aut IRD Chemale F. auteur aut IRD Baby Patrice auteur aut IRD Sanchez C. auteur aut IRD Calderon Y. auteur aut IRD text journalArticle eng text/pdf born digital access Biostratigraphic, sedimentological and provenance analyses suggest that a proto-Andean Cordillera already existed in southern Peru by late Maastrichtian-late Palaeocene times. A 270-m-thick stratigraphic section shows changes in depositional environments from shallow marine (early Maastrichtian) to non-marine (late Maastrichtian) then back to estuarine (late Palaeocene) conditions. An erosional surface separates lower Maastrichtian from upper Maastrichtian deposits. Above this surface, the late Maastrichtian unit exhibits moderately developed palaeosols and syn-sedimentary normal faults. The sedimentary evolution is accompanied by a decrease in sedimentation rate and by changes in provenance. Shallow marine lower Maastrichtian deposits have a cratonic provenance as shown by their low epsilon Nd(0) values (-15 to -16) and the presence of Precambrian inherited zircon grains. The upper Maastrichtian deposits have a mixed Andean and cratonic origin with epsilon Nd(0) values of similar to 12.6 and yield the first Cretaceous and Permo-Triassic zircon grains. Estuarine to shallow marine upper Palaeocene deposits have an Andean dominant source as attested by higher epsilon Nd(0) values (-6 to -10) and by the presence of Palaeozoic and Late Cretaceous zircon grains. The changes in depositional environments and sedimentation rates, as well as the shift in detrital provenance, are consistent with a late Maastrichtian-late Palaeocene period of Andean mountain building. In agreement with recently published studies, our data suggest that an Andean retroarc foreland basin was active by late Maastrichtian-late Palaeocene times. specialized PEROU MADRE DE DIOS BASSIN ANDES 064 30 1 17-23 2018 0954-4879 https://www.documentation.ird.fr/hor/fdi:010072044 10.1111/ter.12303 0954-4879 [F B010072044] https://www.documentation.ird.fr/hor/fdi:010072044 https://www.documentation.ird.fr/intranet/publi/2018/02/010072044.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2018-03-05 2023-07-11 fdi:010072044 fre