Protactinium-231 Dating of Carbonates by Thermal Ionization Mass Spectrometry: Implications for Quaternary Climate Change
Measurement of protactinium-231 (231Pa) in carbonates by thermal ionization mass spectroscopy yields 231Pa ages that are more than 10 times more precise than those determined by decay counting. Carbonates between 10 and 250,000 years old can now be dated with 231Pa methods. Barbados corals that have identical 231Pa and thorium-230 (230Th) ages indicate that the timing of sea level change over parts of the last glacial cycle is consistent with the predictions of the Astronomical Theory. Two Devils Hole calcite subsamples record identical 231Pa and 230Th ages, suggesting that the chronology of this climate record is accurate.
Edwards
RL
R. L. Edwards and H. Cheng, Minnesota Isotope Laboratory, Department of Geology and Geophysics, University of Minnesota, Minneapolis, MN 55455, USA. M. T. Murrell and S. J. Goldstein, Chemical Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Cheng
H
Murrell
MT
Goldstein
SJ