Composition and source of the clay‐sized fraction of Saalian till in The Netherlands

Abstract

The clay mineral composition of a number of Saalian till samples from The Netherlands shows a large variation in smectite and illite abundances. The samples were selected according to their source area, as inferred from coarse erratic components. Specimens containing primarily rock fragments indicative of East and East‐Central Baltic areas are associated with no or low smectite percentages in their clay fractions. Those with mainly flint and rock fragments indicative of the West Baltic areas have high smectite contents in the clay. In general the smectite‐rich material is found in the lower portions of the Saalian till bed, whereas the smectite‐poor occurs in the upper portions. The linkage between very fine and coarse till components in the upper smectite‐free parts of the till suggests that this entire till has been subjected to englacial transport over distances of at least 1000 km.

Subglacial bed conditions during Late Pleistocene glaciations and their impact on ice dynamics in the southern North Sea

“…The lower Saalian tills are stiff sandy tills, both on land (van den Berg & Beets 1987) and on the Netherlands continental shelf (Joon et al 1990; Laban 1995). Based on heavy mineral assemblages, the stiff tills both on land and in boreholes offshore to the north and west of the study area can be characterized as of West‐Baltic provenance (Haldorsen et al 1989; Sha et al 1991; Laban 1995). The NE–SW orientation of seismic lines that show cross‐sections of glaciotectonic structures in our study (Fig.…”

“…The stiff lower Saalian tills are smectite‐rich and sandy in composition (Haldorsen et al 1989; Sha et al 1991; Laban 1995). Haldorsen et al (1989) attributed the high smectite content of the clay fraction to long‐distance transport from sedimentary rocks in Scandinavia.…”

“…The stiff lower Saalian tills are smectite‐rich and sandy in composition (Haldorsen et al 1989; Sha et al 1991; Laban 1995). Haldorsen et al (1989) attributed the high smectite content of the clay fraction to long‐distance transport from sedimentary rocks in Scandinavia. In our opinion, however, it is equally possible that at least part of the smectite is derived from the clays that filled the Elsterian glacial valleys (Irion & Zöllmer 1999), as truncation of the valley fills is visible in the seismic data (Fig.…”

A Silurian–Devonian acritarch flora from Saalian till in The Netherlands

“…Because mixing during transport is highly unlikely (see above) it must be concluded that transport occurred in a relatively high englacial position, as previously suggested by e.g. Rappol ( 1983) and Haldorsen et al (1989). The fact that the clast is still present as such and only shows non-penetrative deformation indicates that it has been deposited (lodged) in one piece at the Steenwijk locality.…”

Heavy minerals as a tool to reconstruct river activity during the Weichselian glaciation (Toruń Basin, Poland)

“…The heavy-mineral assemblage of the tills consists commonly of garnet (15-35%), amphibole (5-25%) and biotite (up to 30%), whereas amphibole (10-35%) dominates over garnet (15-30%;Racinowski, 2010) in the glaciofluvial sands. A similar high amount of amphibole and garnet derived from Palaeozoic and Precambrian rocks in the eastern central Baltic was found in Saalian tills in The Netherlands and in Weichselian tills in north-eastern Germany (Rappol & Stoltenberg, 1985;Haldorsen et al, 1989;Górska, 2006). The deposits of the rivers which were not fed by meltwater are characterised by the domination of garnet (30-45%) and in most cases an insignificant amphibole and biotite content (less than 10%: Racinowski, 2010).…”