New Quartz Optical Stimulated Luminescence Ages for Beach Ridges on the St. Vincent Island Holocene Strandplain, Florida, United States

Abstract

Abstract St. Vincent Island, located on the northwest Gulf of Mexico coast of Florida, U.S.A., preserves a well-developed beach ridge plain that is generally believed to have begun to form during the mid-Holocene period. This study evaluates the potential of optical stimulated luminescence (OSL) to appraise the proposed evolution and progradation of this strand-plain. Optical stimulated luminescence was used to obtain the ages of the quartz samples extracted from seven vibracores at two depth intervals. The single-aliquot regenerative-dose (SAR) OSL ages increase from the shores on the Gulf of Mexico to St. Vincent Sound. The younger ridge set yielded ages of 370 ± 49 to 1890 ± 292 years (AD 2004 datum) conferring an interridge accretion time range of 78 to 148 years assuming uniform sediment accumulation. The oldest ridge set yielded ages of 2733 ± 404 to 2859 ± 340 years, consistent with the estimated age based on archaeological materials of 3000–4000 years ago. For the southwestern beach ridge set, the...