Etude lithostratigraphique, biostratigraphique et sédimentologique du sondage de Lessines (bord méridional du Massif du Brabant, Belgique)

The Lessines borehole was drilled in the Dender valley. Sedimentary rocks of this borehole are subdivided in four informal lithostratigraphic units. Units I and II, dated as Uper Ordovician (graptolites, chitinozoans, acritarchs), show a progressive transition from thin- to medium-bedded mudstone-siltstone rhythmic alternations to black shales. These sediments were mostly deposited by turbiditic flows (high and low density) in a deep clastic lower slope to basin plain setting. Unit III, formed by thin- and wavy-bedded siltstone ("quartzophyllades') of Tremadocian age (acritarchs), is interpret... Mehr ...