Stable carbon and oxygen isotope ratios of groundwaters from the Chalk and Lincolnshire Limestone

SAMPLES of groundwater have been collected from the Chalk of the London Basin and the Lincolnshire Limestone in eastern England to determine the radiocarbon and the 13C/12C ratio in the dissolved carbonate species, and the 18O/16O and D/H ratios of the water. The results will be published more fully elsewhere, but here we report preliminary findings of the 13C/12C and 18O/16O ratios and their implications.