Evidence for a Waalian thermomer pollen record from the research borehole Heidelberg UniNord, Upper Rhine Graben, Baden-Württemberg

Abstract. A pollen record from the borehole Heidelberg UniNord, in the northern Upper Rhine Graben shows evidence for one of the rare Waalian thermomers. The record may not comprise the complete thermomer it certainly reflects a sort of succession, initiated by sequences with high values of pine and spruce, followed by a dominance of pine, hemlock-spruce and spruce and finished by a dominance of hemlockspruce, oak and hornbeam becomes visible. Pollen percentage values for Tsuga reach 20 % indicating that this taxon is an important forest element. There is a continuous presence of Carya, Pterocarya, Eucommia, Celtis and Ostrya-type. Neighbouring pollen records reveal similar patterns. The pollen diagram is closely related with the Waalian profiles Leerdam and Eindhoven from the Netherlands.