Original paper
Calcareous nannofossil biostratigraphy and biochronology across the Eocene-Oligocene transition: the record at IODP Site U1509 (Tasman Sea) and a global overview
Viganò, Allyson; Dallanave, Edoardo; Alegret, Laia; Westerhold, Thomas; Sutherland, Rupert; Dickens, Gerald R.; Newsam, Cherry; Agnini, Claudia
Newsletters on Stratigraphy Volume 57 Number 1 (2024), p. 1 - 23
106 references
published: Jan 10, 2024
published online: May 5, 2023
manuscript accepted: Mar 13, 2023
manuscript revision received: Nov 16, 2022
manuscript revision requested: Oct 21, 2022
manuscript received: Aug 8, 2022
ArtNo. ESP026005701001, Price: 29.00 €
Abstract
The abundance, wide distribution, and high evolutionary rates of calcareous nannofossils provide a powerful and reliable tool for correlating and dating marine sedimentary records, especially during the Cenozoic. Their assemblage turnover has been documented extensively across the Eocene-Oligocene transition (EOT), but without a parallel framework toward detailed biostratigraphy. We present highly resolved semi-quantitative calcareous nannofossil data from a continuous Eocene-Oligocene transition record recovered during International Ocean Discovery Program (IODP) Site U1509 (Expedition 371), presently located at 34.4° S latitude in the New Caledonia Trough (Tasman Sea). We present an improved age model for sedimentation at this site based on integrated bio-magnetostratigraphy. Our high resolution biostratigraphic data provide an independent age calibration for biohorizons, both established and additional, which we compare to previous biochronological estimates from low-middle and high latitudes. This allows for a critical evaluation of the accuracy, reliability, synchroneity or diachroneity of each biohorizon across different oceanographic domains. Finally, we infer that Site U1509 belonged to the subtropical low-middle latitude domain during the late Eocene to early Oligocene, with a paleolatitude of ~45°S. This result has important implications for paleoceanographic reconstructions.
Keywords
calcareous nannofossils, biostratigraphy, biochronology, Eocene-Oligocene transition, IODP Site U1509.