Paleomagnetic dating and effects of Weichselian periglacial processes on the magnetization of early Pleistocene deposits (southern Netherlands, northern Belgium)

Abstract

Early Pleistocene deposits of the Dutch-Belgian border area between Breda and Turnhout have been dated with paleomagnetic methods. Two normal polarity subzones in the sedimentary sequence are identified as the Olduvai and Jaramillo subchrons. The magnetozones are compared with the early Pleistocene pollenzones which are based on ecological changes reflecting Quaternary climatic variations. The Olduvai subchron was identified in pollenzones Tiglian C4 and C5 and the Jaramillo subchron in pollenzone Bavelian Bv3b. Late Pleistocene Weichselian periglacial processes clearly influenced the remanent magnetization of the early Pleistocene deposits. Melting of the icerich topzone of the Weichselian permafrost apparently modified the original remanence and led to complete remagnetization of the upper part of early Pleistocene clay beds.