Gregory W. L. Hodgins Miguel F. Etayo-Cadavid C. Fred T. Andrus Daniel H. Sandweiss Kevin B. Jones 2010 <p><span>Mollusk shells provide brief (&lt;5 yr per shell) records of past marine conditions, including marine radiocarbon reservoir age (</span><i><span class="italic">R</span></i><span>) and upwelling. We report 21&nbsp;</span>^{<span class="sup">14</span>}<span>C ages and&nbsp;</span><i><span class="italic">R</span></i><span>&nbsp;calculations on small (∼2 mg) samples from 2&nbsp;</span><i><span class="italic">Mesodesma donacium</span></i><span>&nbsp;(surf clam) shells. These shells were excavated from a semi-subterranean house floor stratum&nbsp;</span>^{<span class="sup">14</span>}<span>C dated to 7625±35 BP at site QJ-280, Quebrada Jaguay, southern Peru. The ranges in marine&nbsp;</span>^{<span class="sup">14</span>}<span>C ages (and thus&nbsp;</span><i><span class="italic">R</span></i><span>) from the 2 shells are 530 and 170&nbsp;</span>^{<span class="sup">14</span>}<span>C yr;&nbsp;</span><i><span class="italic">R</span></i><span>&nbsp;from individual aragonite samples spans 130±60 to 730±170&nbsp;</span><span class="sup">1⁴</span><span>C yr. This intrashell&nbsp;</span>^{<span class="sup">14</span>}<span>C variability suggests that&nbsp;</span>^{<span class="sup">14</span>}<span>C dating of small (time-slice much less than 1 yr) marine samples from a variable-</span><i><span class="italic">R</span></i><span>&nbsp;(i.e. variable-upwelling) environment may introduce centuries of chronometric uncertainty.</span></p> application/pdf 10.1017/S0033822200046282 en University of Arizona Centuries of marine radiocarbon reservoir age variation within archaeological Mesodesma Donacium shells from Southern Peru article