Evaluation of influence on the radiocarbon dating by the difference in chemical pretreatment protocols

Yamada, Ryuji*; Kokubu, Yoko   ; Wakatsuki, Tsuyoshi*; Yasue, Kenichi

Mass movements and fault movements are natural phenomena to change the local topography. Reconstruction of the movement histories and evaluation of long-term stability of topographies are crucial to assess the geological environment in future. History reconstruction based on radiocabon dating of plant material recovered from sediment deposited by the past movements requires the compilation and the comparison of existing data measured by different analysts with different methods. We compared the results of radiocarbon ages measured at different laboratories with various chemical pretreatments, using plant material samples. For older samples (about 45000 BP), dispersion in ages is greater than measurement uncertainty. However the order of weighted mean ages for each sample agrees well with stratigraphic sequence at the sampling site. It is therefore thought that the influence of the systematic error due to a specific experimental conditions is small.