Issues with radiocarbon dating
These radiocarbon dates of peat inception must then be confronted with palaeocological and archaeological data.Although radiocarbon dating is currently used to date peat initiation, various difficulties can be encountered when attempting to identify and sample the oldest basal layers in amire, and these problems are rarely addressed.3.5 decays/gram/minute of carbon would be produced by a sample 11,460 years old.
Therefore, radiocarbon dates are calculated to a "pre-bomb" age of 1950 A. Material which died after 1950 has such high amounts of radiocarbon its age is reported as "percent modern (1950)" (example 180% modern).
This bomb radiocarbon has been gradually removed from the atmosphere by by natural processes, but the "bomb spike" can be shown through the dating by means such as comparing the bottle date and radiocarbon age of wines.
This paper proposes amethodology based on detailed investigation by means of stratigraphical, sedimentological and micromorphological analyses. As a main result we illustrated the great importance of micromorphological analysis.
We also show that many radiocarbon dates are required to obtain accurate age estimations of the chronology of peat inception, precise enough to be confronted with other palaeoenvironmental data.
Cet article propose une méthode d’échantillonnage des couches basales de tourbe fondée sur un travail minutieux de restitution des stratigraphies couplé à des analyses sédimentologiques et à des examens micromorphologiques.