Petrographical Analysis of Warthian Fuvioglacial Gravels as a Tool to Trace the Source Area – A Case Study From Central Poland
Publié en ligne: 23 oct. 2014
Pages: 183 - 199
Reçu: 21 janv. 2014
Accepté: 06 août 2014
DOI: https://doi.org/10.2478/logos-2014-0014
Mots clés
© 2014 Maria Górska-Zabielska and Lucyna Wachecka-Kotkowska
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.
The petrographical features of the medium- and coarse-grained gravels (4-10 mm and 20-60 mm, respectively) of weathered and fresh (unweathered) deposits indicate, in combination with so-called indicator and statistical erratics, that two glacial lobes joined in the borderland of the Polish Lowlands and Uplands. Lower Palaeozoic limestones become less frequent in the fner gravel fraction, whereas crystalline rocks and fints become more frequent. The petrographical analysis of the coarser gravel fraction indicates that the ice sheet advanced from the NE to NNW (the Widawka lobe) and from the NE to ENE (the Rawka, Pilica and Luciąża lobes). The source areas of the gravel deposited by the Warthian ice sheet were magmatic and sedimentary areas of both the Baltic and the SE Sweden basins.