Sea-level history of past interglacial periods from uranium-series dating of corals, Curaçao, Leeward Antilles islands

Abstract

Curaçao has reef terraces with the potential to provide sea-level histories of interglacial periods. Ages of the Hato (upper) unit of the "Lower Terrace" indicate that this reef dates to the last interglacial period, Marine Isotope Stage (MIS) 5.5. On Curaçao, this high sea stand lasted at least 8000. yr (~126 to ~118 ka). Elevations and age of this reef show that late Quaternary uplift rates on Curaçao are low, 0.026-0.054. m/ka, consistent with its tectonic setting. Ages of ~200 ka for corals from the older Cortalein unit of the Lower Terrace correlate this reef to MIS 7, with paleo-sea level estimates ranging from -3.3. m to + 2.3 m. The estimates are in agreement with those for MIS 7 made from other localities and indicate that the penultimate interglacial period was a time of significant warmth, on a par with the present interglacial period. The ~400 ka (MIS 11) Middle Terrace I on Curaçao, dated by others, may have formed from a paleo-sea level of + 8.3 to + 10.0. m, or (less likely) + 17. m to + 20 m. The lower estimates are conservative compared to previous studies, but still require major ice sheet loss from Greenland and Antarctica. © 2012.