The Silurian of the Mehaigne valley (brabant massif Belgium) - biostratigraphy (chitinozoa)

The Chitinozoa were studied in a 2100 m thick Silurian sequence of flysch-type sediments in the Mehaigne area (Brabant Massif, Belgium). Lower and middle Wenlock graptolites occur only in the middle part of the sequence. Moderately to poorly preserved Chitinozoa from 56 samples belong to 10 genera and 35 species and can be used to establish 5 assemblage zones of which some are divided in subzones. Comparison with Sweden and Great Britain permits these zones to be dated as spanning the Late Ordovician and the middle Llandovery to early or middle Ludlow. Probably the Chitinozoa were deposited originally in the outer deeper shelf and carried off shore by turbidity currents into the Mehaigne area