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Reservoir Effect of Coastal Waters Off Western and Northwestern Galicia

Published online by Cambridge University Press:  18 July 2016

António M Monge Soares*
Affiliation:
Dep. de Química, Instituto Tecnológico e Nuclear, Estrada Nacional 10, 2685-953 Sacavém, Portugal
João M Alveirinho Dias
Affiliation:
Faculdade de Ciências do Mar e do Ambiente, Universidade do Algarve, Campus de Gambelas, 8000-117 Faro, Portugal. Email: jdias@ualg.pt
*
Corresponding author. Email: amsoares@itn.pt
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Abstract

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Differences in the radiocarbon ages of closely associated marine mollusk shells and terrestrial material (charred wood or bones) from several Galician archaeological contexts are significant from the Iron Age to Medieval times. δR values show high variability, ranging from −280 ± 70 to 270 ± 40 14C yr. The set of δR values also presents a strong positive peak (δR = 270 ± 40 14C yr) at 860 ± 90 BP, which matches another peak found for western Portuguese coastal waters. The data obtained, namely the negative or close to zero δR values, suggest that the reduced offset between atmospheric and surface water 14C content is due to the existence of a strong stratification of the water column and environmental factors in the Galician rías during the Iron Age and the Medieval period.

Type
Articles
Copyright
Copyright © 2007 by the Arizona Board of Regents on behalf of the University of Arizona 

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