HR: 11:05h
AN: PP32A-04    [Abstracts]
TI: New constraints on Quaternary sea level oscillations provided by U-series measurements of a submerged speleothem from the Italian coastline
AU: * Dutton, A
EM: Andrea.Dutton@anu.edu.au
AF: Research School of Earth Sciences, The Australian National University, 1 Mills Rd., Canberra, ACT 0200 Australia
AU: Esat, T M
EM: Tezer.Esat@anu.edu.au
AF: Research School of Earth Sciences, The Australian National University, 1 Mills Rd., Canberra, ACT 0200 Australia
AU: Desmarchelier, J M
EM: Jol.Desmarchelier@anu.edu.au
AF: Research School of Earth Sciences, The Australian National University, 1 Mills Rd., Canberra, ACT 0200 Australia
AU: Antonioli, F
EM: fabrizio.antonioli@casaccia.enea.it
AF: ENEA, via Anguillarese 301 S. Maria di Galeria, Rome, 00060 Italy
AU: Lambeck, K
EM: Kurt.Lambeck@anu.edu.au
AF: Research School of Earth Sciences, The Australian National University, 1 Mills Rd., Canberra, ACT 0200 Australia
AU: McCulloch, M T
EM: Malcolm.Mcculloch@anu.edu.au
AF: Research School of Earth Sciences, The Australian National University, 1 Mills Rd., Canberra, ACT 0200 Australia
AB: Speleothems have become increasingly important as tools to place long paleoenvironmental records into a temporal context through the use of U-Th dating, which is one of the most precise and accurate geochronometers available for the late Quaternary. This investigation was designed to provide U-series ages for a stalagmite collected from a submerged cave on Argentarola Island to constrain the timing, duration, and magnitude of Quaternary sea-level highstands. Argentarola cave has been alternately submerged and subaerially exposed as evinced by the presence of marine encrustations of {\it Serpulid} calcite that alternate with dense, microcrystalline speleothem calcite that forms during subaerial exposure. As such, speleothems from Argentarola cave provide a unique archive of the relative height of Quaternary sea level oscillations along a portion of the Italian coastline that appears to have been tectonically stable on the time scales considered here. Moreover, the application of U-series dating to these speleothems can provide an estimate of the absolute timing and relative duration of Quaternary marine transgressions. We have studied a stalagmite that was collected 18 meters below present sea level. Preliminary results indicate speleothem growth during stage 8, in addition to stages 2, 6 and 7.2 that have previously been identified, and define marine layers that correspond to the Holocene transgression and highstands associated with marine isotope stages (MIS) 5, 7.1, and 7.3. Because few relative sea level (RSL) indicators exist for glacial cycles prior to the last interglacial, data from Argentarola speleothems provide important benchmarks for future RSL models and also provide an important test for existing models. Our data are generally in good agreement with RSL curves for this time period and indicate that the correlation between RSL and foraminiferal \delta$^{18}$O over the last glacial cycle is a robust predictive tool for RSL estimates extending back to the initiation of MIS 8.
DE: 4556 Sea level variations
DE: 1035 Geochronology
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting