This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Granted funds will support continued operation of the Amino Acid Racemization Geochronology Laboratory (AAGL) at Northern Arizona University. Racemization of amino acids following the death of an organism is proportional to time elapsed since death and the temperature of the reaction environment. AAR geochronology therefore provides a tool to date fossil remains for which the temperature history of the environment can be inferred or for paleothermometry if the age of the sample is determined independently (e.g., radiocarbon dating). Sample analysis is rapid and inexpensive and sample size requirements are minimal, allowing for dating of individual microfossils, for example. Research applications of AAR dating range from paleoceanographic investigations to studies of invertebrate evolution. AAR fills an important niche in our ability to date sediments beyond the 45 ka limit or radiocarbon dating (AAR can used back to ca. 150 ka). In addition, the technique can be used to date, in a relative sense, individual microfossils in mixed assemblages and therefore assist in unraveling the paleoenvironmental history of bioturbated marine and lacustrine sediments. Results from research that employs AAR dating provides constraints on the timing of major shifts in Earth?s climate and thus helps us to better understand the potential consequences of human activities on Earth?s climate system. Support for this facility will result in the continued employment of a full time technician at Northern Arizona University.
