No abstract

This paper presents the outcome of a workshop, held in Berlin in February 2009, concerned with current research on the glacial history of northern Europe, including the British Isles. The methodologies presently used to resolve this topic are outlined. Particular attention is given to new analytical methods deriving from high resolution remote imaging of glacial terrain both on land and on the sea-bed, key new stratigraphic sections, higher resolution results from conventional geochronological methods like radiocarbon and more recently developed technologies such as luminescence and cosmogenic radionuclide dating. The relationships between the results derived from these two methods are discussed in further detail along with possible explanations for these differences. An outline of a 'most likely' glacial history of the Scandinavian and British and Irish Ice Sheets is presented along with possible links to global climate change as represented by the marine isotope (MIS) record. Tentative evidence for glaciation is identified in MIS 22, 16, 12, 10, 8, 6, 4 and 2 and correlations of 'phases' within the Last Glaciation are also explored for both the Scandinavian and British and Irish Ice Sheets. The results show that the character and extent of glaciation in different parts of the region are not synchronous and much more geochronological work is required before regional correlations can be established with confidence. Keywords: glaciation, marine isotope stages (MIS), Scandinavian Ice Sheet (SIS), British and Irish Ice Sheet (BIIS), Last Glacial Maximum Introduction and objectivesThe glaciation of northern Europe has been a subject of interest and debate for over 200 years and today, at a time of greater awareness to the consequences of climate change, the subject retains its relevance to science and society. With the development of new methodologies for dating glacial deposits and important new findings for modelling glacier response to climate change this subject requires re-evaluation and re-interpretation. Likewise it has been possible to identify critical issues that should be the focus for future research. Consequently, in February 2009 an exploratory workshop was held at the Freie Universität Berlin to examine the frequency and timing of glaciations in northern Europe (including Britain) during the Middle and Late Pleistocene. The workshop was funded by the DFG (Deutsche Forschungsgmeinschaft/ German Research Foundation) and involved 24 participants. This issue of Quaternary Science Reviews includes a number of the contributions presented and discussed at the meeting along with certain invited papers that present new findings on the topic of the special issue. This paper will begin by briefly reviewing the contents of the issue giving particular attention to new and important findings. This will be followed by a section that will evaluate the methodologies currently being applied to understand the glaciations of northern Europe. Some of these methodologies, such as lithostratigraphy and morphostratig...

 Users may download and print one copy of any publication from the public portal for the purpose of private study or research.  You may not further distribute the material or use it for any profit-making activity or commercial gain  You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.

The timing, structure, and landscape change during the Patagonian Ice Sheet deglaciation remains unresolved. In this article, we provide a geomorphic, stratigraphic, and geochronological deglacial record of Río Cisnes Glacier at 44°S and also from the nearby Río Ñirehuao and Río El Toqui valleys (45°S) in Chilean Patagonia. Our 14C, 10Be, and optically stimulated luminescence data indicate that after the last glacial maximum, Río Cisnes Glacier experienced ~100 km deglaciation between >19.0 and 12.3 ka, accompanied by the formation of large glacial paleolakes. Deglaciation was interrupted by several ice readvances, and by 16.9±0.3 ka, Río Cisnes Glacier extended only ~40% of its full glacial extent. The deglaciation of Río Cisnes Glacier and other sensitive Patagonian glaciers occurred at least 1 ka earlier than the ca. 17.8 ka normally assumed for the local termination, coincident with West Antarctic isotope records. This early deglaciation can be linked to an orbital forcing–driven decline of Southern Ocean sea ice associated with a distinct atmospheric warming that is apparent for West Antarctica through Patagonia.

No abstract

During the penultimate glaciation vast areas of the Alps were glaciated, with piedmont glaciers protruding into the foreland. In the easternmost part of the northward draining valleys of the Alps, the glaciers did not reach the foreland, but formed valley glaciers confined by the mountainous terrain. This also applies to the Ybbs valley, where samples for luminescence dating out of glaciofluvial gravel accumulations were taken at three locations along the present day river course. In a highly dynamic depositional environment, such as a glacier-fed river system, incomplete resetting of the luminescence signal is possible, in particular when transport distances are short. In such cases, quartz usually is the preferred mineral over feldspar, especially if dose rates are low and may theoretically allow obtaining quartz ages beyond 150 ka. Because previous research has shown, and as corroborated within this study, quartz from the research area exhibits analytical problems in the high age range. Therefore luminescence properties of coarse grain (100–200 μm) quartz and in addition K-rich feldspar were investigated with the aim to reconstruct the chronology of the glacial processes within the Ybbs catchment area. Issues of incomplete bleaching were pIRIR225 encountered and addressed by comparing quartz OSL, fading corrected K feldspar IR50 and pIRIR225 to identify reliable ages. Depositional ages based on quartz OSL and feldspar pIRIR225 signals revealed deposition of ice marginal kame terraces and glaciofluvial foreland terraces during late to middle MIS 6. In combination with results from previous studies, we could reconstruct the valley evolution during the Riss glaciation. Newly gained luminescence ages of the deglaciation in the easternmost Alps coincide with OSL dated deglaciation events in the Western Alps, indicating that climatic change along the north side of the Alps happened simultaneously.

No abstract

No abstract