Plans for expanded 14C analyses at the NOSAMS facility – a status and progress report

Abstract

After completion of the original main program – radiocarbon analysis of over 13000 seawater samples from the World Ocean Circulation Experiment (WOCE) – the NOSAMS Facility has entered a new phase of its operation. Major areas of concentration will be: (a) Continuation of analyses of “normal size” marine samples (including additional seawater samples from WOCE follow-up studies), (b) analysis of small samples (≪100 μg C), (c) analysis of individual compounds or compound classes, and (d) continuous-flow AMS (see contribution elsewhere in these proceedings). While (a) could be considered routine work, we intend to intensify our efforts to drive down the systematic uncertainties of our analyses. The other three areas all yield small samples, requiring new techniques in sample handling and AMS analysis. The facility plans to devote one of its two existing ion sources (134-sample NEC MC-SNICS) to the “routine” work, the other (59-sample “846”) will be upgraded to better accommodate small samples, and a new, separate small AMS system will be developed for continuous-flow AMS. The latter is expected to become the instrument of choice for individual-compound work. Until that device comes online, tests of the continuous-flow injector are planned on the main AMS system, temporarily adding a third injector leg. A planned enlargement of the facility will house the new AMS system, additional staff and laboratory space.