Knowing the ages of geological materials is pivotal to understanding the timing, rates, and regional extent of past environmental changes.  The Amino Acid Geochronology Laboratory (AAGL) at Northern Arizona University is dedicated to estimating the ages of Quaternary deposits by analyzing the extent of racemization in amino acids preserved within carbonate fossils.  Amino acid geochronology is used to solve a variety of Quaternary stratigraphic, paleoclimatic, taphonomic, neotectonic, and other problems that require information on the timing, frequency, and rates of Earth surface processes.  In addition, the AAGL investigates the processes, rates, and temperature sensitivity of amino acid diagenesis in fossils to refine the method for geochronology and paleothermometry.

Recent research sponsored by the American Chemical Society is aimed at using new procedures developed in the AAGL to analyze individual microfossils from marine and lacustrine deposits.  The ability to analyze extremely small samples has opened up major new potential for amino acid geochronology.  By analyzing sample sizes that are an order of magnitude smaller (~0.1 mg) than previously required, it is now possible to integrate amino acid geochronology and paleothermometry into the study of lake and marine sediment cores to derive more complete time series than was possible previously using infrequent mollusk shells.

For more information on amino acid geochronology, and on my projects and publications related to amino acid geochronology, please visit the AAGL web site or click on the "Lab" link above.