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Abstract: For the first time, electron spin resonance optical dating (ESROD) has been conducted on littorally transported and aeolian siliciclastic sediments in Florida. ESROD utilizes light-sensitive radiation-sensitive defects at silicon sites that have been replaced by aluminum and titanium atoms to give rise to a time-dependant signal. These defects saturate at higher levels of radiation dose, compared to optically stimulated luminescence, and therefore extend the optical dating range back into the millions of years. Our results show that the Trail Ridge Sequence is a multi-depositional unit that began deposition around 2.2Ma and continued until 6ka. The Osceola Cape, of the Effingham Sequence, was deposited around 1.5Ma, and the Chatham Sequence was a multi-depositional terrace with at least three events preserved. [Copyright &y& Elsevier]

Ground penetrating radar and single-aliquot regenerative-dose optically stimulated luminescence were used to determine the depositional environments and age of unconsolidated siliciclastic sediments near Apalachicola, Florida. Five direct-push cores, five vibracores and 28 optically stimulated luminescence samples were collected, as well as 7 km of ground penetrating radar data. A new model of cosmic dose rate calculation, which removes the effect of a much younger aeolian cap, was utilized to calculate more representative optically stimulated luminescence ages. Five radar facies were identified based on reflector amplitude and orientation. The resulting data indicate that the Tertiary/Quaternary Shelly Sediments were deposited before marine isotope stage 6, the Quaternary Alluvium was deposited during marine isotope stage 6 and the Quaternary Beach Ridge and Dune was deposited during the marine isotope stage 5e sea-level highstand, which peaked at approximately 2·5 m above present sea-level in this area. [ABSTRACT FROM AUTHOR]