New marine ΔR values for Arctic Canada

For more than four decades, the reporting of C-14 dates on marine molluscs from Arctic Canada has been notable for the lack of consistently applied marine reservoir corrections. We propose that the common approach of reporting Canadian Arctic marine C-14 dates using presumed time-invariant reservoir corrections be abandoned in favour of calibration of C-14 dates, using the current standard protocol. This approach best facilitates inter- and intra-regional correlation, and correlation with other geo-chronometers. In order to enable the consistent calibration of marine C-14 dates from Arctic Canada, we analysed a C-14 database of 108 marine mollusc samples collected live between 1894 and 1956, and determined regional reservoir offset values (Delta R) for eight oceanographically distinct regions. The following new Delta R values should be used for C-14 calibration: NW Canadian Arctic Archipelago, 335 +/- 85 yrs; Foxe Basin, 310 +/- 90 yrs; NE Baffin Island, 220 +/- 20 yrs; SE Baffin Island, 150 +/- 60 yrs; Hudson Strait, 65 +/- 60 yrs; Ungava Bay, 145 +/- 95 yrs; Hudson Bay, 110 +/- 65 yrs; and James Bay, 365 +/- 115 yrs. (C) 2010 Elsevier B.V. All rights reserved.