Erotic AGROVOC: AGROVOC: oxygen isotope dating Pictures
The Oxygen and Iostope Isotope Ratio The oxygen isotope ratio is the first way used to determine past temperatures from the ice cores. Isotopes are atoms of the same element that have a different number of neutrons.
During cold periods the glaciers grow, water is drawn up into them, and the proportion of Isotpoe increases. There are two ways of obtaining data about eMthods 16O to 18O ratio, both using measurements made using a mass spectrometer.
When used for dating, this AMS method involves actually counting individual carbon atoms. This allows the dating of much older and smaller samples but at a far higher cost.