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For exceptions, permission may be sought for such use through Elsevier's permissions site at: http://www.elsevier.com/locate/permissionusematerial From: Daniel Nývlt, Zbyněk Engel and Jaroslav Tyráček, Pleistocene Glaciations of Czechia. In J. Ehlers, P.L. Gibbard and P.D. Hughes, editors: Developments in Quaternary Science, Vol. 15, Amsterdam, The Netherlands, 2011, pp. 37-46. ISBN: 978-0-444-53447-7 © Copyright 2011 Elsevier B.V. Elsevier. Author's personal copy Chapter 4 Pleistocene Glaciations of Czechia { Daniel Ny´vlt1,*, Zbyneˇ k Engel2 and Jaroslav Tyra´cˇek3, 1Czech Geological Survey, Brno branch, Leitnerova 22, 658 69 Brno, Czech Republic 2Department of Physical Geography and Geoecology, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2, Czech Republic 3Czech Geological Survey, Kla´rov 3, 118 21 Praha, Czech Republic *Correspondence and requests for materials should be addressed to Daniel Ny´vlt. E-mail: [email protected] {This study is dedicated to the memory of our colleague Jaroslav Tyra´cˇek (1931-2010) for his substantial contribution to the study of Pleistocene glaciations in our territory 4.1. INTRODUCTION relatively narrow belt parallel to the general trend ofthe north- ern frontier mountain ridges. The maximum glacial extent is This is a review of current evidence of continental and moun- marked either byglacial deposits orby Nordic rocks spread on tain glaciation in Czechia and provides a closer look at the the land surface. This line has been called the ‘flint-line’ Pleistocene glacial limits and chronology for the region. It (Feuersteinlinie) because the most commonly represented li- is based on numerous works published during more than a thology is flint derived from the Baltic region. More recent century of research in the Czech territory. The reference list, studieshavefocusednotonlyexclusivelyonglacialsediments therefore, can include only the most important studies or but also on glacial erosional morphological features. They those published in world languages. This chapter is divided have provided better control on the exact glacial limits, partic- into two main parts. The first part focuses on the products of ularly in the granite landscapes of northern Bohemia. Numer- the continental glaciations, whilst the second part deals with ous sedimentological and petrological studies of glacial ˇ the local mountain glaciations in the Sudetes and the Sumava deposits from Czechia (e.g. Ru˚zˇicˇka, 1980, 1995; Ny´vlt and Mountains. Three Northern European ice sheets affected Hoare, 2000, 2011; Sikorova´ et al., 2006; Vı´sˇek and Ny´vlt, Czech territory during both the Elsterian (marine isotope 2006) are not discussed here, except for those which are di- stage (MIS) 16 and 12) and older Saalian (MIS 6) glaciations. rectly connected to the topic of this contribution. Dating of in- They reached as far as northern Bohemia, northern Moravia dividual ice-sheet advances has also been the subject of recent and Czech Silesia. In contrast, mountain glaciation was lim- studies,but onlya few results havebeenpublished todate (e.g. ˇ ited to the Krkonosˇe (Giant), the Sumava (Bohemian Forest) Ny´vlt, 2008; Ny´vlt et al., 2008). However, further studies are and Hruby´ Jesenı´k(Altvatergebirge in German) Mountains. in progress and will be published in the near future. The timing of mountain glaciation is still poorly known. Sed- Czech territory contains evidence of three Middle Pleis- imentary and numerical evidence is available for both the tocene glaciations during which glaciers advanced into two Weichselian-age glaciations, but the chronostratigraphical regions, northern Bohemia and northern Moravia, and to a framework of the pre-Weichselian glaciation remains ques- larger extent into Czech Silesia. The area was especially tionable. Recent geomorphological, sedimentological and invaded by ice of the Polish Odra lobe (e.g. Hesemann, chronological studies have substantially improved the un- 1932; Piotrowski, 1998). Only the eastern glaciated part of derstanding of Pleistocene glaciations in Czechia, providing northern Moravia and Czech Silesia was glaciated by ice new information on their extent and chronology. sheets that combined both the Vistula and Odra lobes (e.g. Marks, 2005). The local morphology at the glacier margin 4.2. CONTINENTAL GLACIATION affected the extent of the ice sheets, such that the glaciers penetrated further to the south in the low-lying Zittau and The first evidence of continental glaciation in Czechia was al- Ostrava Basins or in the Moravian Gate. The fronts of the ready established by the end of the nineteenth century (e.g. advancing ice-sheet lobes crossed the local or regional Danzig, 1886; Tausch, 1889; Cammerlander, 1891). Czech watersheds in some places. The main European watershed territory was marginally overridden by northern European was crossed by the ice at the Poruba Gate, and the associated ice sheets during three separate events. They left behind con- proglacial outwash drained into the Danube River catchment siderable masses of glacial sediments, arranged mostly in a (e.g. Tyra´cˇek, 1961, 1963, 2011). The Sudetes mountain belt Developments in Quaternary Science. Vol. 15, doi: 10.1016/B978-0-444-53447-7.00004-0 ISSN: 1571-0866, # 2011 Elsevier B.V. All rights reserved. 37 Author's personal copy 38 Quaternary Glaciations - Extent and Chronology was crossed by an outlet of the ice sheet in the Jı´trava Saddle, superposition at different sites (Sˇibrava, 1967). Here the thereby penetrating into the inner part of the Bohemian High- Elsterian 1 glaciation was the most extensive, the ice-sheet lands, that is, to the Labe (Elbe) River catchment (e.g. Dan- front crossed the Jı´trava and Hornı´ Saddle and penetrated zig, 1886; Sˇibrava, 1967; Macoun and Kra´lı´k, 1995). These further to the Ralsko Hilly land (Sˇibrava, 1967; Kra´lı´k, key areas are important for direct correlation of glacial se- 1989). The Elsterian 2 ice front crossed also the Jı´trava Sad- quences with fluvial terrace-deposit systems of the rivers dle and deposited a terminal moraine at Jı´trava (Sˇibrava, in the Labe and Danube catchments (e.g. Sˇibrava, 1967; 1967; Kra´lı´k, 1989). Proglacial glaciofluvial accumulations Macoun and Kra´lı´k, 1995; Tyra´cˇek and Havlı´cˇek, 2009; Tyr- deposited in the Ploucˇnice river catchment have been a´cˇek, 2011). Morphostratigraphical correlation was for- correlated with the terrace deposits sequence of the Labe merly the only available approach for dating of individual River (Grahmann, 1933; Sˇibrava, 1967; Tyra´cˇek and glacial deposits and landforms. Individual stratigraphical Havlı´cˇek, 2009). systems, based on these correlations, were developed for Remnants of both Elsterian glaciations are also found in the continental glaciation in northern Bohemia and northern the Fry´dlant Hilly land (Kra´lı´k, 1989; Macoun and Kra´lı´k, Moravia and Czech Silesia (the most recent are given by 1995). Here it seems that the Elsterian 1 glaciation was Macoun and Kra´lı´k, 1995 or Ru˚zˇicˇka, 2004). less extensive than that during the subsequent Elsterian 2 (Kra´lı´k, 1989; Ny´vlt, 2003). The ice sheet crossing of the 4.3. ELSTERIAN GLACIATIONS Jizerske´ hory mountain belt, through the Oldrˇichov col at 478 m a.s.l. (Kra´lı´k, 1989), took place during the Elsterian Traditionallytwo separate advancesofNorthern European ice 2 Stage (Ny´vlt, 2003; Ny´vlt and Hoare, 2011). The glacia- sheets reaching the northern parts of Czechia were linked to tion limit in the northern slope of the Jizerske´ hory, which is the Elsterian Stage (e.g. Sˇibrava, 1967; Macoun, 1985). They connected with the Elsterian 2 ice sheet, was recently are correlated with MIS 16 and 12 (e.g. Sˇibrava et al., 1986; mapped by Cˇ erna´ 2011. Here the glaciation limit was Lindner et al., 2004) and locally to Elsterian 1 and 2 in delimited using a combination of different geomorpholog- Germany (Eissmann, 1997, 2002)ortheSanian1and2in ical methods to the altitude of 470–490 m a.s.l. (Traczyk Poland (Lindner et al., 2004; Marks, 2004, 2005). Individual and Engel, 2006; Cˇ erna´ 2011; Cˇ erna´ and Engel, 2011; glaciations are described separately for both glaciated areas of Fig. 4.2). The highest site with glacial sediments in northern Czechia, they could be correlated via the area of Poland. Bohemia lies in the Andeˇl Saddle at 522 m (Jana´skova´ and Engel, 2009), in the northern part of the Jizerske´ hory. Here 4.3.1. Northern Bohemia the glaciation is represented by proglacial glaciofluvial sed- iments deposited in front of the ice-sheet advancing to the During the Elsterian 1 (MIS 16¼Donian glaciation of saddle from the east. The precise position of the glacier has Russia; Chapter 26), the Northern European ice sheet cov- not been determined, but the glacier’s surface must have ered Sˇluknov Hilly land, Fry´dlant Hilly land and Zittau Ba- been higher than that of the saddle, because its melt waters sin, the frontal lobe crossed the Jı´trava Saddle in the Jesˇteˇd were draining to the west (Jana´skova´ and Engel, 2009). Range and entered the Ralsko Hilly land, that is, the catch- Eissmann (1997, 2002) proposed the concept of a huge ments of Ploucˇnice and Jizera Rivers (Sˇibrava, 1967; ice-dammed lake in the Labe River valley upstream of Kra´lı´k, 1989; Macoun and Kra´lı´k, 1995; Ny´vlt, 2008).
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