Diagenetic reactions used most commonly in amino acid geochronology:
a) racemization of L- and D-enantiometers with a single chiral carbon (e.g. leucine, aspartic acid)
b) epimerization of L- and D- diastereomers (e.g. isoleucine)
Because the racemization / epimerization rate differs depending on the position of the amino acid in the
peptide chain, the rate of hydrolysis influences the rate of racemization.