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USGS · 70011975

210 Pb method for estimating the rate of carbonate sand sedimentation

Charles W. Holmes
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Abstract

The plot of 210 Pb activity against depth in carbonate sands on the Virgin Island Bank is a negative asymmetric hyperbolic curve. As depth increases, an initial rapid decrease in 210 Pb activity caused by the decay of unsupported 210 Pb and 226 Ra is followed by increasing activity as a result of 210 Pb achieving equilibrium with in growing 230 Th. As this curve is time dependent, an estimate of the relative ages in carbonate sequences and the rates of net carbonate accumulation can be made. The ease of 210 Pb activity determinations makes this procedure an attractive method in obtaining carbonate sand accumulation rates.

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Geo-Marine LettersArticle

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Charles W. Holmes. 1981. 210 Pb method for estimating the rate of carbonate sand sedimentation. https://doi.org/10.1007/bf02462440

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