MAXIMUM SEA LEVELS FOR THE LAST GLACIAL PERIOD FROM U-SERIES AGES OF SUBMERGED SPELEOTHEMS

PLEISTOCENE sea Levels reflect changes in the surface distribution of land, sea and ice, which in turn significantly influence the Earth's c limate1. The most complete record of sea levels for the last glacial c ycle has come from raised coral reef terraces of the Huon Peninsula, P apua New Guinea2-4, but interpretation of this record is hampered by r elatively large age uncertainties and the possibility of variation in the rate of tectonic uplift. Subaerial speleothems (stalagmites, stala ctites and flowstones) from submerged caves in tectonically stable are as provide an alternative source of data5-8, as their growth stops whe n rising sea levels flood the caves. Previous studies of speleothems h ave been limited by dating precision5,6 and sample availability5-7. He re we present high-precision thermal-ionization mass-spectrometric Th- 232 ages9-11 for a comprehensive suite of speleothem samples from the Bahamas. Our results provide a record of maximum elevation of sea leve ls for the period from 80 to 10 kyr before the present, for much of wh ich sea levels are poorly known. We also find that regional palaeoclim atic change can be an important factor in the termination of speleothe m growth.