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Abstract Eskers are common glacial landforms in Ireland and form regionally-extensive networks that reflect stages of ice retreat of this sector of the late Devensian (Weichselian) British–Irish ice sheet. However, the sedimentary structures and composition of these eskers are poorly known, despite being able to offer valuable insight into subglacial hydrological processes during deglaciation. This study presents detailed morphological and sedimentary evidence from six esker systems in north-central Ireland, where adjacent and interacting ice domes were characterized by changes in ice-bed thermal and hydrological properties as well as significant ice dome centre migration. Morphologically, esker ridges in this area vary in length, size and continuity, with some esker systems ascending over hills (thus crossing watersheds) whereas other systems are confined to basin settings. Esker systems commonly appear to feed terminal outwash and glaciolacustrine deltas, but several systems do not show a clear terminus. The internal sediments within eskers vary from concentrically-bedded sands and gravels formed within enclosed tunnels, to interbedded sands, gravels and diamictons, occasionally with water-induced soft-sediment deformations, that are likely formed in interlobate settings. In contrast with some previous glacier models that assume that esker systems are isochronous and were formed in solely subglacial settings, the esker systems described here are interpreted as being of different ages, formed in variously subglacial to ice-marginal settings, and thus cannot be used as a single snapshot of the disposition of ice domes during stages of late Devensian ice retreat. [ABSTRACT FROM AUTHOR]

The depositional history of the Virttaankangas plain, a fan-like enlargement of the large Sa¨kyla¨nharju glaciofluvial ridge in SW Finland, is examined. The Sa¨kyla¨nharju ridge has been interpreted as having formed as an interlobate esker, and the morphology of the Virttaankangas plain as representing predominantly subaqueous glaciofluvial to glaciolacustrine deposition. This investigation uses new sedimentologic outcrop data, with extensive subsurface drilling, GPR surveys, seismic soundings, and gravimetric measurement data provided by groundwater investigations, to describe the stratigraphy, morphology and depositional history of the plain.In contrast to earlier interpretations, the results emphasise the role of littoral processes in the origin of the Virttaankangas plain. The plain is interpreted as having originated during the development of a progradational sequence of spit-platform and superimposed nearshore sediments deposited during the glacio-isostatic forced regression of the Yoldia Sea and Ancylus Lake phases of the Baltic Basin (9900–9000 14C BP). Documented depositional history supports an interval of retarded regression at the beginning of the Ancylus Lake phase I (9500–9200 14C BP) in the Sa¨kyla¨nharju area. [Copyright &y& Elsevier]

A complex assemblage of fluvial and lacustrine sediments is identified in a major section through proglacial sediments on Skeiðara´rsandur, south Iceland. High magnitude–low frequency events are identified in both the fluvial and lacustrine sediments. However, much of the sedimentary succession is composed of ‘normal’ low magnitude–high frequency sediments. Retreat of Skeiðara´rjo¨kull following a surge event created a topographic basin occupied at various times by both fluvial and lacustrine depositional systems and also subjected to a high magnitude jo¨kulhlaup. Previous studies have examined the processes and events occurring on Skeiðara´rjo¨kull in isolation. This paper improves the understanding of the way in which processes with varying magnitude and frequency regimes interact and contribute to the sedimentary record of proglacial environments. [Copyright &y& Elsevier]