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This research was carried out in north-central Poland, which was occupied by the ice sheet of the Saalian (Marine Isotope Stage [MIS] 6) and Upper Stadial of the Weichselian (MIS 2) glaciation. The application of the anisotropy of magnetic susceptibility (AMS) method supported by a digital elevation model (DEM) analysis of the orientation of glacial landforms allowed for the reconstruction of ice-sheet extent and ice movement directions of these two Pleistocene glaciations. The research used an innovative method of collecting AMS till samples from the glacial plateau areas. Based on the research, it was found that during the general recession of the ice sheet of the Saalian glaciation, a previously undescribed glacial transgression occurred, characterized by a different direction of ice-sheet movement. On the basis of detailed geomorphological studies of the area of terminal moraines, previously described in fragments, the maximum extent of the ice sheet during the Weichselian glaciation was clarified. The recession of the ice sheet of the Weichselian glaciation from the area of north-central Poland took place in four regressive or transgressive–regressive stages with variable directions of ice-sheet movement. The results obtained indicate the great potential of the AMS method in paleoenvironmental studies of glaciated areas. [ABSTRACT FROM AUTHOR]

This paper presents five sites located in the marginal zone of the Wartanian stadial within the Odranian Glaciation (MIS6a) on the border of the Central Polish Uplands and Lowlands, representing different glacial forms and geological structures: terminal moraine hill, undulating moraine hill, sedimentary margin of the ice sheet, kame hill, and outwash plain. This differentiation is also reflected in the petrographic composition of the gravels and the interesting surface microstructures of the Scandinavian erratic boulders. This small study area, with its high geodiversity, which we have identified and investigated, has considerable potential for sustainable development. Geotourism is a tool for this development in a peripheral tourist region, providing both economic benefits for the local population and conservation services for the geoecosystem. [ABSTRACT FROM AUTHOR]

It is speculated that an united East Siberian-Chukchi Ice Sheet (ESCIS) existed on the East Siberian-Chukchi margin during the Pleistocene era. However, details regarding the frequency of its occurrence and the intensity of each glaciation remain unclear. Critical information lies in the northern part of the East Siberian-Chukchi margin because this region preserves relatively complete glacial landforms and deposits, especially in areas of deep-water depths. In this paper, new full-coverage multibeam data from the outer shelf–ocean basin on the western side of the Chukchi Rise of the northwestern Chukchi margin are presented, and more complete submarine glacial landforms in this area are identified. In addition, we provide a more detailed interpretation of the entire glacial strata using a compilation of new sub-bottom profiler data. Interpreted glacial landforms and buried glaciogenic debris flows (GDFs) indicate that the western side of the Chukchi Rise was affected by the Chukchi Ice Sheet. Overall, the glacial landforms can be divided into two categories, i.e. those in an ice stream setting on the Southwestern Margin and an inter-ice stream setting on the Northwestern Margin. However, in the current inter-ice stream area, large old gullies and GDFs persist, indicating dynamic changes between the ice stream and inter-ice stream zones. Since the onset of glaciation began around ∼0.8 Ma, the study area has experienced a total of nine glaciations, including three intense glaciations, five intermediate glaciations, and 1 mild glaciation. Through a comparison with the GDFs on the eastern slope of the Arliss Plateau which locates further west of the Chukchi Rise, we infer the existence of at least four unified ESCISs during the Quaternary. • New multibeam and subbottom profiler data at the northwestern Chukchi margin reveal more complete glacial landforms. • Nine glaciations of varied intensity are inferred by nine generations of glacigenic debris flows. • At least four unified East Siberian-Chukchi Ice Sheets existed during the Quaternary. [ABSTRACT FROM AUTHOR]

Sites of ice-stream discharge to the continental slope build trough-mouth fans from glacigenic debris flows (GDFs), subglacial meltwater flows, and suspended sediment. Thus, past ice configurations may be interpreted from the sedimentological record. This study links the records in cores, high-resolution seismic profiles, and multibeam swath bathymetry of Hatton Slope and Fan to the changing glaciological history in Hudson Strait, one of the largest ice streams of the late Pleistocene Laurentide Ice Sheet. 14C-AMS dates, X-ray fluorescence geochemical profiles, and oxygen isotopes in sixteen cores document sediment supply during the last glacial cycle, and earlier history is interpreted from seismic data. The Frobisher Bay slope sector has a long record of GDF deposits from severe glacial periods between MIS 6 and 22, with little impact of meltwater discharge. Mass-transport events and aggrading gravel-floored valleys dominate the northern Hatton slope sector. The central slope sector shows the greatest shelf break progradation by till deposition, with kilometre-spaced gullies heading at 700–730 mbsl from the last major grounding of the ice-stream on the upper slope during Heinrich event 3 (H3). The gullies pass downslope into ∼5 km wide valleys, which have been sites of sediment bypass since widespread meltwater flow in MIS 6 and show little aggradation since MIS 16. Intervening >50 m high ridges show alternating levee accretion and erosion by shallow mass-transport events. Downslope on Hatton Fan, GDFs are common and fill wide erosional channels that lead to the sandy braid plain of the central Labrador Sea. The channels of the southern sector and Saglek Slope have channeled turbidity currents down the NAMOC, and stratified contourite deposits accumulated on the fan. Over the MIS 1–3 period widely represented by cores, ice was grounded in Hatton Basin and on the upper slope to 700 m water depth only immediately prior to H3. Older and younger H events had a floating ice-shelf in Hatton Basin, and sedimentation was dominated by the retreat of that ice shelf to Resolution Island. Distal cores show no systematic difference between the H1–top H3 interval and the base H3–H5 interval. Given the supply of carbonate detritus of consistent composition back to at least H5, any MIS 3 deglaciation of Hudson Bay would require improbably high growth rates of ice sheets in the centre of the continent. • First multibeam swath bathymetric and seismic profiling of the Hudson Strait Ice Stream. • Glacigenic debris flows, and mass-transport events were outlined during MIS 6 and 16. • Glacial ice was grounded in Hatton Basin and on the upper slope to 700 m over MIS 1-3. • Lack of a systematic difference between H1–H3 and H4–H5 events raises the question about the deglaciation hypothesis during MIS 3. [ABSTRACT FROM AUTHOR]