Τίτλος:
Foraminifera eco-biostratigraphy of the southern Evoikos outer shelf, central Aegean Sea, during MIS 5 to present
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
The South Evoikos Basin is a marginal basin in the Aegean Sea which receives little terrigenous supply and its sedimentation is dominated by hemipelagic processes. Late Quaternary benthic and planktonic foraminifera from core PAG-155 are investigated in order to understand their response to the glacial-interglacial cycles in this region. The quantitative analysis of planktonic foraminifera, coupled with accelerator mass spectrometry (14C-AMS) radiocarbon date measurements, provide an integrated chrono-stratigraphic time framework over the last 90 ka (time interval between late Marine Isotopic Stages 5 and 1; MIS5-MIS1). The temporary appearance and disappearance as well as several abundance peaks in the quantitative distribution of selected climate-sensitive planktonic species allowed the identification of several eco-bioevents, useful to accurately mark the boundaries of the eco-biozones widely recognized in the Mediterranean records and used for large-scale correlations. The established bio-ecozonation scheme allows a detailed palaecological reconstruction for the late Pleistocene archive in the central Aegean, and furthermore provides a notable contribution for palaeoclimatic studies, facilitating intercorrelations between various oceanographic basins. The quantitative analyses of benthic foraminifera identify four distinct assemblages, namely Biofacies: Elphidium spp., Haynesina spp. Biofacies, characterized by neritic species, dominated during the transition from MIS 5 to MIS 4; Cassidulina laevigata/carinata Biofacies dominated till 42 ka (transgressive trend from MIS 4 to MIS 3); Bulimina gibba Biofacies dominated from 42 ka to 9.5 ka (extensive regression MIS 3,2 through lowstand and early transgression; beginning of MIS 1); Bulimina marginata, Uvigerina spp. Biofacies dominated from 9.5 ka to the present (late transgression through early highstand; MIS 1)., This study showed that the South Evoikos Basin which is characterized by its critical depths and connections to the open sea, and its small volume water masses that nourished foraminiferal assemblages, accurately records 5th−4th order sea level and climatic fluctuations. Especially, the basin's limited communication with the open ocean implies that any climatic signals will be recorded in an amplified fashion, and therefore this heightened sensitivity to the effects of climate variability further underlies the prominent role of such marginal basins in the understanding of the global climatic evolution. © 2016 Elsevier Ltd
Συγγραφείς:
Drinia, H.
Antonarakou, A.
Tsourou, T.
Kontakiotis, G.
Psychogiou, M.
Anastasakis, G.
Περιοδικό:
CONTINENTAL SHELF RESEARCH
Εκδότης:
Elsevier Ireland Ltd
Λέξεις-κλειδιά:
benthic foraminifera; benthos; biofacies; biostratigraphy; biozonation; climate variation; glacial environment; glacial-interglacial cycle; global climate; marginal sea; marine isotope stage; open ocean; planktonic foraminifera; quantitative analysis; sea level change; water mass, Aegean Sea; Evvoikos Gulf; Mediterranean Sea, Bulimina; Bulimina marginata; Cassidulina; Elphidium; Foraminifera; Haynesina; Uvigerina
DOI:
10.1016/j.csr.2016.07.009
