The influence of the development of a Weichselian coversand ridge on the drainage of a river valley in Noord Brabant (The Netherlands); A geomorphological and palynological study

Abstract

Pollen analysis of cores from an area with a river valley that is blocked by a coversand ridge shows that the three beds of which the ridge consists were deposited respectively before the Lateglacial, during the Earlier Dryas stadial, and after the Allerød interstadial. During the first part of the Lateglacial the valley was only partly obstructed and occupied by a local Cyperaceae vegetation. Later, from the Earlier Dryas stadial onward, the valley became completely blocked and that resulted in a change in drainage pattern. The pollen diagrams show a local lacustrine environment, caused by the progressing obstruction of the valley. Wetter and drier phases are recorded in the sediments and mark the climatic development during the Lateglacial.