Heterogeneity in homogeneous Brabantian loess during the Late Pleniglacial

The Brabantian loess is often seen as a homogeneous sediment package, deposited under cold and dry climatic conditions (Haesaerts et al., 1981). However, in 1981 two small tundra gleysols were discovered in the Brabantian loess (Haesaerts et al., 1981). To unravel other possible changes in the sedimentary system during deposition, a more detailed look at the homogeneous Brabantian loess is carried out. The loess transporting process is reconstructed based on the combination of both grain size and grain shape parameters. These parameters are defined with automated dynamic image analysis and statistically compared with the two-dimensional Kolmogorov-Smirnov test. As suggested by Vandenberghe et al. (1998), our gleysols are generally correlated to a period of reduced grain size. Most likely, the more subtle the gleysols, the weaker the link between their formation and grain size reduction. Mazzullo et al. (1992) already stated that aeolian transport was very selective regarding grain size and sorting capacities. Our research points toward an extremely selective aeolian transport regarding the shape of the grains. Therefore, combining both particle size and particle shape can be very useful when reconstructing aeolian transport processes. This combination can also discriminate samples with a different transport and sedimentation history.

Publication year:2009

Keywords:Paleoclimate, Brabant, Loess, Glaciation