87Sr/86Sr variability in Puerto Rico: geological complexity and the study of paleomobility
نویسندگان
چکیده
The temptation to use biogeochemical techniques to resolve issues of paleomigration is evident and well intentioned. Knowledge of radiogenic strontium isotope baselines in a region of interest is a sine qua non of such archaeological studies of paleomobility. Here, we present the first detailed study of baseline 87Sr/86Sr values for the island of Puerto Rico. The high degree of 87Sr/86Sr variability present in this corpus of modern Puerto Rican bedrock and terrestrial malacological samples (0.70406e0.70909) is a testament to the complex geology of that island. This diversity of 87Sr/86Sr values makes parsing issues of origin a difficult and highly contingent task. Given these complexities, regional studies seeking to assess paleomigration by such isotopic means should proceed with a great deal of caution. ! 2013 Elsevier Ltd. All rights reserved.
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