HR: 0800h
AN: OS11A-0193    [Abstracts]
TI: Reconstructing Radiocarbon Variability in the Bismark Sea for the Past 50 years
AU: * Burr, G S
EM: burr@u.arizona.edu
AF: University of Arizona, Physics Department, Tucson, AZ 85721-0081, United States
AU: Taylor, F
EM: fred@ig.utexas.edu
AF: University of Texas at Austin, Institute for Geophysics 10100 Burnet Road, Austin, TX 78758, United States
AU: Quinn, T
AF: University of Texas at Austin, Institute for Geophysics 10100 Burnet Road, Austin, TX 78758, United States
AU: Carey, A
AF: University of Arizona, Physics Department, Tucson, AZ 85721-0081, United States
AB: We present a surface ocean radiocarbon time series derived from a Porites colony which grew near Rabaul, Papua New Guinea. The record covers about 50 years of growth, from the 1940s to 1998, and has been sampled with seasonal resolution (4 samples per year). The coral survived the September 19, 1994 eruption of the Tavurvur vent at Rabaul, which can be seen in X-radiographs of the core. The record features a 170 permil increase in Ä14C starting in the 1960s and tapering off since the 1980s. This increase is relatively large, as compared with other South Pacific coral sites. The record reflects interannual radiocarbon variations with amplitudes between 10 and 20 permil before and after the introduction of "bomb" carbon. Data from the 1940s and early 1950s show a tight clustering of radiocarbon values with Ä14C = -56.5±1.0 permil (29 measurements). The radiocarbon data are examined in terms of regional surface ocean circulation and compared with other coral records from the region.
DE: 0428 Carbon cycling (4806)
DE: 1040 Radiogenic isotope geochemistry
DE: 1115 Radioisotope geochronology
DE: 4806 Carbon cycling (0428)
DE: 4916 Corals (4220)
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting