A magnetostratigraphic reassessment of correlation between Chinese loess and marine oxygen isotope records over the last 1.1 Ma

We present a magnetic polarity-based paleoclimatic correlation between Chinese loess and marine oxygen isotope stage (MIS) records over the last 1.1 Ma. This revised land–ocean comparison indicates that inconsistent occurrence of the Matuyama/Brunhes Boundary, which lies in MIS 19 in marine sediments and occurs either at the base/lower part of loess L8 or the uppermost part of soil S8 in Chinese loess, is due to regional and/or local climate variability across the Chinese Loess Plateau, and does not need to be attributed to lock-in effects of loess remanence acquisition associated with pedogenesis. This result implies that the geomagnetic polarity boundaries in Chinese loess in general are reliable chronostratigraphic time markers. Therefore astronomically tuned timescales for Chinese loess that presume a downward shift of polarity boundaries due to a time lag in remanence acquisition may have overestimated ages of certain loess/paleosol units.