Mollusk shells provide brief (<5 yr per shell) records of past marine conditions, including marine radiocarbon reservoir age (R) and upwelling. We report 21 14C ages and R calculations on small (∼2 mg) samples from 2 Mesodesma donacium (surf clam) shells. These shells were excavated from a semi-subterranean house floor stratum 14C dated to 7625±35 BP at site QJ-280, Quebrada Jaguay, southern Peru. The ranges in marine 14C ages (and thus R) from the 2 shells are 530 and 170 14C yr; R from individual aragonite samples spans 130±60 to 730±170 14C yr. This intrashell 14C variability suggests that 14C dating of small (time-slice much less than 1 yr) marine samples from a variable-R (i.e. variable-upwelling) environment may introduce centuries of chronometric uncertainty.
Additional publication details
|Publication Subtype||Journal Article|
|Title||Centuries of marine radiocarbon reservoir age variation within archaeological Mesodesma Donacium shells from Southern Peru|
|Publisher||University of Arizona|