TESTING THEORETICALLY PREDICTED STALAGMITE GROWTH-RATE WITH RECENT ANNUALLY LAMINATED SAMPLES - IMPLICATIONS FOR PAST STALAGMITE DEPOSITION

Annually laminated stalagmites deposited over the last 30-160 years ar e analysed to determine their growth rate. Three natural and artificia l cave sites in England, France, and Belgium were chosen for their wid e range of variability in growth rate determining variables, and multi ple samples were taken from each site. The annual nature of laminae de position within the stalagmite calcite was confirmed by comparison to the date of cave/void opening, C-14 analyses, or by using dated event horizons. Measured stalagmite growth rate was determined from annual l aminae thickness measurements and compared to that theoretically predi cted from the chemical kinetics of the calcite precipitation reaction. A good agreement is observed between empirical observations and theor etical predictions, although two complicating factors, variations in c alcite porosity, and seasonal cessation of the water supply to the sam ples, both affect the growth rate. Implications for the extraction of palaeoclimate information from stalagmite growth rate are discussed. C opyright (C) 1998 Elsevier Science Ltd.