A magnetostratigraphic comparison between 14C years and varve years during the Late Weichselian, indicating significant differences between the time‐scales

Abstract

AbstractA 14C‐dated magnetostratigraphy of absolute declination and inclination between 12500 and 10000 14C yr BP was recently developed for southern Sweden. Recently also the Swedish geochronological time‐scale, based on c. 11 500 annually deposited clay‐varves, was connected with the present. It should therefore be possible to compare the two chronologies with a reliable magnetostratigraphic record in an appropriate clay‐varve section. We have found such a site within the Middle Swedish end‐moraine zone. Statistical correlations between the two independently dated time‐scales suggest that at 10500–10200 14Cy r BP the varve chronology exceeds the 14C chronology by the order of 500‐600 varve yr. Other correlations indicate that the difference between the two chronologies was less at 11000 14C yr BP, and further correlations between the time‐scales at 12000 14C yr BP suggest that the difference between the chronologies increased steadily from 12000 to 10000 14C yr BP. If these correlations are correct they imply that the 14C production rate increased steadily during the Late Weichselian.