form distinct groups form distinct groups http://www.psrd.hawaii.edu/Dec01/Oisotopes.html théorie proposée par Shu et al http://www.psrd.hawaii.edu/Dec01/Oisotopes.html very sensitive indicators http://www.psrd.hawaii.edu/Dec01/Oisotopes.html http://www.psrd.hawaii.edu/Dec01/Oisotopes.html very sensitive indicators http://www.psrd.hawaii.edu/Dec01/Oisotopes.html isotopic composition can be used as a tool http://www.psrd.hawaii.edu/Dec01/Oisotopes.html Sauerstoffisotopie isotopic composition can be used as a tool