Jürgen Ehlers

Glacial deposits in north-west Europe

Until now no overview of the Quaternary deposits of northeastern Europe has been available. This book fills the gap. It presents the state of research on Quaternary stratigraphy and geology, with emphasis on glacial deposits, discusses the general scientific ideas and gives an overview of the methods of investigation, some of which have rarely been applied elsewhere. It has become apparent that the region covered has many environmental problems, and a proper understanding of the Quaternary deposits is a basic requirement for dealing with them. The same is true for civil engineering. In the formerly glaciated areas almost all construction sites for roads and houses will encounter glacial deposits. This volume provides an authoritative and fascinating overview for anyone planning to venture into this field. In its 53 regional chapters the book covers Finland, Estonia, Latvia, Lithuania, Russia, Ukraine, Belarus, Poland, the Czech Republic and eastern Germany. From the text it becomes clear that not all the stratigraphical schemes are yet fully compatible or comprehensible. There can be no doubt, however, that the east was subjected to very extensive ice advances during the earlier Pleistocene. Also, in contrast to western Europe, there was a significant Early Weichselian ice advance, although not as extensive as the last, Late Weichselian event. The book is illustrated by 421 figures and 74 colour plates (mostly photographs). There are 23 tables, a detailed index and a list of over 1000 references, providing a unique collection of northeastern European geoscience literature, much of which has so far escaped the attention of western scientists. The volume, composed of contributions by 60 scientists, completes the trilogy on glacial deposits of northern Europe. Together with its two companion volumes, the Glacial deposits in North-West Europe and the Glacial Deposits in Great Britain and Ireland, it represents an invaluable source of information for the geoscientist, the advanced student or the amateur.

The pre-weichselian glaciations of North-West Europe

Abstract In North-West Europe no evidence has been found for glaciations older than the Elsterian. The Elsterian seems to consist of at least two separate ice advances with a minor interval in between. During the Elsterian in the area south of the Baltic Sea over 400 m deep channels were cut into the underlying substratum by a combination of glacial erosion and meltwater activity. The channels were active until the Late Elsterian and were subsequently filled with meltwater deposits and glaciolacustrine silt and clay. During the Saalian no comparative channels were being formed. Three different ice advances can be distinguished within the Saalian, the stratigraphical correlation of which is to be discussed. No convincing evidence was found for any interglacial within the Saalian sequence. There are good reasons to assume that the ice advances were only separated from each other by minor ice-free intervals.

Pleistocene glaciations of North Germany

This chapter discusses the Pleistocene glaciations of North Germany. The oldest glaciation represented by widespread till sheets in Northern Germany is the Elsterian Glaciation. During the advance of the Elsterian ice the drainage system was completely rearranged: rivers that mostly drained toward the Baltic Sea were partly dammed by the advancing ice sheet and forced to alter their courses. Consequently, the Elsterian tills in major parts of Thuringen, Sachsen, and Sachsen–Anhalt are both under and overlain by varved clays. The Elbe River was dammed and formed a large lake south of Dresden, but drainage was westward rather than to the south. Further to the east, rivers drained via the “Moravian Gate” toward the Danube and Black Sea. During the Weichselian Glaciation the lower Elbe Valley between the Havel River mouth and the North Sea served continuously as the main drainage path parallel to the ice margin, so that no changes of river course had to be made.

Reconstructing the dynamics of the North-west European Pleistocene ice sheets

Abstract The flow lines of the North-west European Pleistocene ice sheets can be reconstructed with the aid of fabric measurements and glaciotectonic investigations. From this there is evidence for a more extensive Saalian Glaciation of the North Sea area than previously assumed. With regard to the Weichselian, different glaciological models can be tested against the field evidence. ‘Deformable bed’ and ‘instantaneous glaciation’ may be partially responsible for the observed phenomena. However, while at the end of the Weichselian there was fast moving ice largely following the course of the Baltic Sea depression, during the Weichselian maximum conventional radial ice flow, as envisaged by Hughes et al. (1981), was dominant. Directional evidence suggests that fast moving Baltic ice was present during the late stages of the Older and Younger Saalian glaciations. However, possibly as a result of isostatic effects, it occupied a more southerly position than during the Weichselian.

Extent and chronology of glaciations

Abstract The goal of the INQUA Commission on Glaciation Work Group 5 ‘Extent and Chronology of Glaciations’ was to assemble glacial chronologies from around the world to better understand ice sheet volumes and extents at various times, and to compile a GIS-supported database for past ice sheet extents. The project involved the contribution of over 200 scientists working in more than 80 countries and territories throughout the world. The resulting compilation represents the most complete survey of evidence of glaciation ever attempted. The results are published in the form of three volumes ‘Europe’, ‘North America’ and ‘South America, Asia, Africa, Australia, Antarctica’ (Quaternary Glaciations—Extent and Chronology, Part I: Europe, 2003a; Quaternary Glaciations—Extent and Chronology, Part II: North America, 2003b; Quaternary Glaciations—Extent and Chronology, Part III: South America, 2003c), each of which contain a series of maps in digital format accompanied by an explanatory text which includes discussion of the type and quality of data used.

Pleistocene Glaciations of North Germany—New Results

Abstract Deposits from three Pleistocene glaciations are found in north Germany. In most parts of north Germany, the oldest glaciation, the Elsterian, reached furthest south. Only in the west, the ice of the second glaciation, the Saalian, advanced beyond the Elsterian limits. In the last and smallest glaciation, the Weichselian, the ice sheet did not cross the Elbe River.

Elsterzeitliche (Anglian) Eisdynamik in East Anglia

Gefugeuntersuchungen in Aufschlussen in East Anglia haben gezeigt, das wahrend der Elster-Vereisung (Anglian) ein Eisvorstos aus dem Nordseebecken von einem Vorstos britischen Eises erst aus westlicher, spater aus nordlicher Richtung gefolgt wurde. Durch das ungleichzeitige Vorstosen und Abschmelzen der beiden Eisschilde und durch die isostatische Absenkung im Nordsee-Bereich hat sich zeitweise eine nach NE gerichtete Eisbewegung ergeben.