Renewed uplift of the Central Andes Forearc revealed by coastal evolution during the Quaternary
Résumé
Most of the Pacific coast of the Central Andes, between 15°S and 30°S, displays a wide (a couple of kilometres) planar feature, gently dipping oceanwards and backed by a cliff. This morphology, usually of marine orgin, is called rasa, and argues for a recent and spatially continuous uplift of the margin over the 1,500-km-long coastal region we describe. The cliff foot is found at a similar elevation (~110 m amsl) all over the studied area, with the exception of peninsulas such as the Mejillones Peninsula. The compilation of published chronological data and the extrapolation of re-appraised uplift rates provide evidence for a common cliff foot age of around 400 ka (i.e., Marine Isotopic Stage MIS 11). This, together with other geological constraints, indicates a Quaternary renewal of uplift in the Central Andes forearc after a late Pliocene quiescence or subsidence.
Fichier principal
RasaPeruChile_9_pourHAL.pdf (2.28 Mo)
Télécharger le fichier
table_add_mat_EPSL.xls (52.5 Ko)
Télécharger le fichier
| Origine | Fichiers produits par l'(les) auteur(s) |
|---|
| Format | Autre |
|---|
Loading...