Ichnological analysis as a tool for assessing deep-sea circulation in the westernmost Mediterranean over the last Glacial Cycle

• Published in: Palaeogeography, Palaeoclimatology, Palaeoecology
• Main Authors: Casanova-Arenillas, S., Rodríguez-Tovar, Francisco Javier, Martínez Ruíz, Francisca C.
• Other Authors: Ministerio de Educación, Cultura y Deporte (España), Junta de Andalucía, Universidad de Granada, Ministerio de Ciencia e Innovación (España), Ministerio de Economía y Competitividad (España)
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Elsevier BV 2020
• Subjects: Greenland; Greenland ice cores
• Online Access: http://hdl.handle.net/10261/224267; https://doi.org/10.1016/j.palaeo.2020.110082; https://doi.org/10.13039/501100003176; https://doi.org/10.13039/501100004837; https://doi.org/10.13039/501100003329; https://doi.org/10.13039/501100006393; https://doi.org/10.13039/501100011011

During the Last Glacial Cycle (last ~130 kyr) climatically induced changes in the ocean dynamics affected the tracemaker habitat in the Alboran Sea Basin (westernmost Mediterranean), as observed in sediment records from ODP Leg 161 Sites 976 and 977. The trace fossil assemblage present is assigned to the Zoophycos ichnofacies and is of low/moderate diversity and comprises common Planolites, Chondrites and Thalassinoides, with occasional Scolicia and Zoophycos. Ichnodiversity, size of biogenic structures and percentage of bioturbational sedimentary structures clearly correlate. Fluctuations in ichnological features evidence a well-developed short-term cyclic pattern that could be related to environmental changes such as export production and oxygenation at the seafloor. The percentage of bioturbational sedimentary structures correlates well with sea-surface temperature (SST) records obtained for the Alboran Sea and Gulf of Lions, as well as with the δO profiles of Greenland ice cores. Correlation is seen for both the long-term (over the Last Glacial Cycle) and short-term changes, the latter comprising climate oscillations such as Heinrich Events, Younger Dryas, and periods of organic-rich layer deposition. Ichnological data also allow for a reconstruction of climatically induced changes in the ocean dynamics, which have a major incidence in the Western Mediterranean Deep Water that, in turn, affects deep-sea environmental conditions. We thank Palaeo3 Editor and Guest Editor, Dr. Thomas Algeo and Dr. A. Wetzel and Reviewer 1 Dr. Joachim Schönfeld for their detailed revision and valuable comments and suggestions. Research was funded by Projects CGL2015-66835-P, PID2019-104624RB-I00 and PID2019-104625RB-100 (Secretaría de Estado de I + D + I, Spain), B-RNM-072-UGR18 (FEDER Andalucía), P18-RT-3804 and P18-RT-4074 (Junta de Andalucía), and Scientific Excellence Unit UCE-2016-05 (Universidad de Granada). The research of SC-A is funded through a pre-doctoral grant from the Ministerio de Educación, Cultura y Deporte ...