Valdes J. auteur aut IRD Sifeddine Abdelfettah auteur aut IRD Guinez M. auteur aut IRD Castillo A. auteur aut IRD text journalArticle eng text/pdf born digital access Mejillones bay presents a permanent and shallow OMZ, whose upper boundary fluctuates between 30 m and 60 m water depth during a normal year. Under this condition, the bottom sediments preserve a geochemical signature of the past oceanic variability. Particularly, biological productivity and bottom dissolved oxygen can be reconstructed using 13C, 15N and trace elements metals measured along sediment cores. Trace elements like V, Ni, Mo and U preserved in surface sediment of Mejillones bay as a consequence of poorly oxygenated bottom waters, were used to develop a statistical model that allowed the reconstruction of the bottom water dissolved oxygen variability during the last 700 years. During these seven centuries, the marine sediments of Mejillones recorded three ocean-climatic periods. From 1350 to 1500 CE the bay was dominated by a strong and shallower OMZ, intense denitrification, but a low productivity and flux of biodetritus. Bottom waters recorded oxygen values around a mean of 3.52 mu specialized Redox-sensitive metals Paleoxygenation Paleoproductivity Humboldt current Mejillones bay Chile CHILI 032 064 193 102520 [12 ] 2021 0079-6611 https://www.documentation.ird.fr/hor/fdi:010081498 10.1016/j.pocean.2021.102520 0079-6611 [F B010081498] https://www.documentation.ird.fr/hor/fdi:010081498 https://www.documentation.ird.fr/intranet/publi/2021-07/010081498.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2021-07-02 2025-02-24 fdi:010081498 fre