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Chronologia i zasięgi nasunięć lądolodu na obszarze lobu Wisły podczas stadiału głównego ostatniego zlodowacenia

Wysota W., Molewski P.

Przegląd Geologiczny

2011

Vol. 59, nr 3

214-214

During the maximum of the last glaciation the Vistula ice lobe was one of the key morphological elements at southern margin of the Scandinavian Ice Sheet in north-central Poland. The area of the Vistula ice lobe experienced two ice sheet advances of varied extent, the earlier one during the Leszno Phase and the younger one in the Poznań Phase. According to the authors, the limit of the Leszno Phase within the study area was much smaller than hitherto accepted and its age is estimated at about 20.5 ka BP. Significant ice sheet retreat was followed by an ice readvance during the Poznań Phase, overriding the extent of the Leszno Phase. The Poznań readvance reached the maximum limit in the Vistula ice lobe area about 18.5 ka BP. It is assumed that the rapid ice sheet transgression during the Poznań Phase (on average 400 m/a) and origin of the Vistula lobe were probably connected with activity of the palaeo-ice stream.

Streamlined topographical features in and around the Gulf of Riga as evidence of Late Weichselian glacial dynamics

Tsyrulnikov A., Tuuling I., Hang T.

Geological Quarterly

2008

Vol. 52, No 1

81-81

Based on various cartographic sources, a digital terrain model and acoustic profiling data, linear relief features of glacial origin have been distin guished and analysed in the Gulf of Riga and adjacent mainland areas in order to reconstruct the dynamics and pathways of former ice streams. North-east–south-west oriented features in the till topography prevail in the central part of the gulf and along the southern coast of the island of Saaremaa, which corroborate the previously known south/south-east di rection of the main Riga ice stream. North-east to south-west directed features dominate in the Pärnu Bay and around the Irbe Strait. Similar deviations from the Riga ice stream are most likely due to ice divide zones, namely the Sakala Upland in Southern Estonia and Kurzeme in north western Latvia, which locally changed the course of the main ice flow. The influence of the Kurzeme ice divide is traceable at the bottom of the gulf up to the southern coast of Saaremaa. There is no evidence of an ice-marginal zone cross ing the central part of the Gulf of Riga as was supposed earlier. The Pandivere-Neva and Palivere ice-marginal zones, which merge on the Sorve Peninsula, probably continue offshore into the Irbe Strait. As the age of the glacier relieffeatures is poorly contained, the chronologi reconstruction of the ice dynamics is tentative.