Open AccessGeomorphic traces of a Weichselian ice stream in the Wielkopolska Lowland, western Poland
Author(s) -
PRZYBYLSKI BOGUSŁAW
Publication year - 2008
Publication title -
boreas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 74
eISSN - 1502-3885
pISSN - 0300-9483
DOI - 10.1111/j.1502-3885.2007.00023.x
Subject(s) - landform , geology , lineation , ice sheet , geomorphology , ice stream , glacial landform , elevation (ballistics) , physical geography , paleontology , glacial period , cryosphere , oceanography , sea ice , moraine , geography , geometry , mathematics , tectonics
Geomorphological analysis of a digital elevation model reveals an extensive zone with uniformly oriented elongated landforms in the middle and eastern Wielkopolska Lowland, directly to the north of the maximum extent of the Weichselian Ice Sheet. Individual linear landforms are up to 10 km long, a few hundred metres wide, and with only a few metres of relief. The belts of linear landforms visible on the surfaces of the uplands are disrupted by subglacial channels and younger river valleys. The character and distribution of both landform types, in relation to the outlines of marginal zones of the Weichselian ice lobes, indicate that their origin was subglacial. The elongated landforms are interpreted as mega‐scale glacial lineations (MSGLs) characteristic of palaeo‐ice stream zones. The MSGLs occur in a zone 70 km long and 80 km wide and are distinctly divergent towards the maximum extent of the ice sheet. This arrangement demonstrates that they are the record of the terminal zone of the ice stream, whose full size was likely in the order of a few hundred kilometres in length.