Chronostratigraphy of a 270-ka sediment record from Lake Selina, Tasmania: Combining radiometric, geomagnetic and climatic dating ...

• Main Authors: Lisé-Pronovost, Agathe, Fletcher, Michael-Shawn, Simon, Quentin, Jacobs, Zenobia, Gadd, Patricia S, Heslop, David, Herries, Andy IR, Yokoyama, Yusuke
• Format: Dataset
• Language: English
• Published: PANGAEA 2021
• Subjects: Paleomagnetic data; Core; Antarctic; Antarc*; ice core
• Online Access: https://dx.doi.org/10.1594/pangaea.931786; https://doi.pangaea.de/10.1594/PANGAEA.931786

Lake sediment archives covering several glacial cycles are scarce in the Southern Hemisphere and they are challenging to date. Here we present the chronostratigraphy of the oldest continuous lake sediment archive in Tasmania, Australia; a 5.5 m and 270 ka (Marine Isotope Stage 8) sediment core from Lake Selina. We employ radiometric dating (radiocarbon and optically stimulated luminescence) and relative dating (geomagnetic and climate comparisons). Bayesian modeling of the radiometric ages reaches back to 80 ka (1.7 m) and relative dating using a dynamic programing algorithm allows dating of the full sequence. Elemental data, magnetic properties and beryllium isotopes from Lake Selina reveal a close fit to Antarctic ice core climate proxies. Weaker correlation during the Last Glacial Period (MIS 2-4) is attributed to additional local factors impacting Lake Selina proxies at a time of climate changes and human arrival into Tasmania. Over that period, full vector paleomagnetic records and authigenic 10Be/9Be ...