We have applied previously proposed methods for the measurement of equivalent radiation doses in sediment to a marine core from off the gulf coast of Florida for which accurate 14C dates are available up to 25 ka. We observe that the thermoluminescence (TL) from the 4–11 μm grains shows two glow peaks throughout the upper 350 cm of core and that accurate TL apparent ages are obtained from only one of these peaks. Two major difficulties encountered were radon loss from dry powders and overestimation of paleodoses for two samples through inappropriate "sunlamp" exposures. The problem of radon loss was overcome by glassing the samples prior to alpha counting; the overestimated paleodoses were reduced by blocking the < 420 nm spectral component of the sunlamp and by using the R–Γ technique.

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