ISOTOPES IN SPELEOTHEMS

Interest in speleothems (secondary cave carbonates such as stalagmites) as recorders of continental palaeo–environments has increased markedly during the past decade, reflecting the need to provide reliable palaeoclimatic records from a range of continental settings. This renewed interest has been underpinned by important analytical advances that facilitate the acquisition of well–dated oxygen and carbon isotope data at a high spatial resolution, and by emerging methodologies for the extraction of stable isotope signals from speleothem fluid inclusions. Speleothems (mostly calcite, but occasionally aragonite) are deposited slowly by degassing of meteoric water–fed drips in caves. Most studies utilise stalagmites rather than stalactites or flowstones, because their simple geometry, relatively rapid growth rates and tendency to precipitate close to isotope equilibrium with the cave drip waters facilitates palaeoclimatic reconstruction.