• Comparison of U-Series and Radiocarbon Dates of Speleothems

      Goslar, Tomasz; Hercman, Helena; Pazdur, Anna (Department of Geosciences, The University of Arizona, 2000-01-01)
      The paper presents a comparison of U-series and radiocarbon dates of speleothems collected in several caves in central and southern Europe and southeast Africa. Despite a large spread of dates, mainly due to contamination with younger carbon, the group of corresponding 14C and (super 230) Th/U ages of speleothem samples seems to be coherent with the previous suggestion of large deviation between the 14C and the absolute time scale between 35 and 45 ka BP. This agrees with the result of frequency analysis of published 14C and (super 230) Th/U ages of speleothem.
    • Radiocarbon Calibration by Means of Varves versus 14C Ages of Terrestrial Macrofossils from Lake Gościąż and Lake Perespilno, Poland

      Goslar, Tomasz; Arnold, Maurice; Tisnérat-Laborde Nadine; Hatté, Christine; Paterne, Martine; Ralska-Jasiewiczowa Magdalena (Department of Geosciences, The University of Arizona, 2000-01-01)
      This paper presents radiocarbon dates of terrestrial macrofossils from Lakes Gosciaz and Perespilno, Poland. These data agree very well with most of the German pine calibration curve. In the Late Glacial, they generally agree with the data from Lake Suigetsu, Japan, and indicate constant or even increasing 14C age between 12.9 and 12.7 ka BP, rapid decline of 14C age around 12.6 ka BP, and a long plateau 10,400 14C BP around 12 ka BP. Correlation with corals and data from the Cariaco basin seems to support the concept of site-speficic, constant values of reservoir correction, in contradiction to those introduced in the INTCAL98 calibration. Around the Allerod/Younger Dryas boundary our data strongly disagree with those from the Cariaco basin, which reflects large discrepancy between calendar chronologies at that period. The older sequence from Lake Perespilno indicates two periods of rapid decline in 14C age, around 14.2 and 13.9 ka BP.