These are important for amino acid dating because racemization occurs much faster in warm, wet conditions compared to cold, dry conditions.Temperate to cold region studies are much more common than tropical studies, and the steady cold of the ocean floor or the dry interior of bones and shells have contributed most to the accumulation of racemization dating data.The enclosing matrix is probably the most difficult variable in amino acid dating.This includes racemization rate variation among species and organs, and is affected by the depth of decomposition, porosity, and catalytic effects of local metals and minerals.When an organism dies, control over the configuration of the amino acids ceases, and the ratio of D to L moves from a value near 0 towards an equilibrium value near 1, a process called racemization.Thus, measuring the ratio of D to L in a sample enables one to estimate how long ago the specimen died.The rate at which racemization proceeds depends on the type of amino acid and on the average temperature, humidity, acidity (p H), and other characteristics of the enclosing matrix.
While most other dating mechanisms date the rock surrounding fossils, both Amino Acid and Carbon 14 dating .
The rate of racemization of aspartic acid ( D/ L-Asp) was similar to previously published results from an 1800 year old anemone ( Gerardia).
The age equation was: age (years BP 2000 AD) = [( D/ L - 0.020 (±.002))/.0011 (±.0001)] C dating over the most recent 50-200 years, although the dating error may be improved by inclusion of more samples over a broader time range.
AA(Centre for Environmental and Marine Geology, Dalhousie University, Halifax, NS, Canada B3H 4J1), AB(Centre for Environmental and Marine Geology, Dalhousie University, Halifax, NS, Canada B3H 4J1), AC(School of Geography and Geology, Mc Master University, Hamilton, Ont., Canada L8S 4M1) Primnoa resedaeformis is a deep-sea gorgonian coral with a two-part skeleton of calcite and gorgonin (a fibrillar protein), potentially containing long-term records of valuable paleo-environmental information.
For various reasons, both radiocarbon and U/Th dating of these corals is problematic over the last few centuries.