Provenance analysis of the Permo-Carboniferous fluvial sandstones of the southern part of the Boskovice Basin and the Zöbing Area (Czech Republic, Austria): implications for paleogeographical reconstructions of the post-Variscan collapse basins

Abstract

Abstract:The provenance analyses of Permo-Carboniferous fluvial sandstones of the southern part of the Boskovice Basin and the Zöbing area are based on a wide spectrum of analytical techniques (petrography, heavy mineral assemblages, chemistry of garnet, rutile and spinel, zircon study, major and trace elements). The studied sandstones are poorly sorted and reveal a relatively immature composition implying short distance transport, rapid deposition, a high-relief source area, mainly physical weathering and the minor role of chemical weathering. Different source areas for the Boskovice Basin and the Zöbing area were proved. The Zöbing material was predominantly derived from crystalline units, mainly formed by metamorphic complexes, although the portions of magmatic and volcanic material were significant. The source area is supposed to be located in the Moldanubian Unit. The Boskovice Basin deposits, on the other hand, seem to be mainly derived from metamorphic complexes, corresponding especially to the Moravian Unit, with a relatively wider spectrum of metamorphites, together with the derivation of the detritus from pre-existing sedimentary rocks (especially from MoravoSilesian Paleozoic deposits/Drahany Culm unit). The transport direction in the basin was more complex, both from the west and east. These results did not confirm the possibility of communication between the Boskovice Basin and the Zöbing area during the Late Paleozoic. The existence of "colinear" marginally offset half grabens with predominant transversal sources is here hypothesized. The general heavy mineral evolution in time does not indicate the successive exhumation of a simple structured orogen but may be interpreted as differences in the extent of the source areas.

Sedimentological study of the Nikolčice Formation - evidence of the Middle Jurassic transgression onto the Bohemian Massif (subsurface data)

“…The strong dom i nance of pyrop-almandines (close to 80%) is typ i cal of Permo-Car bon if er ous rocks of the Boskovice Ba sin (Nehyba et al, 2012). A sig nif i cant sim i lar ity can be seen with the gar net spec tra from the un der ly ing Gresten For ma tion (Nehyba and Opletal, 2016;Fig.…”

The Lower - Middle Miocene transition (Karpatian – Badenian) in the Krems Embayment (Central Paratethys, Lower Austria): a multistrati-graphic approach and the role of the Diendorf-Boskovice Fault System.

“…However, the complete Karpatian succession was not accessible by the core. Northeast of this site and east of an adjoined nabel et al, 2002), names of faults from Roetzel (1996), Lenhardt et al (2007) and Nehyba et al (2012).…”

“…Figure 11: Geological map and major fault lines, particularly of the Diendorf-Boskovice Fault System, in the Krems Embayment, and location of investigated drill cores with thicknesses of Badenian and Karpatian sediments. Local geology and faults based on the geological map of Lower Austria(Schnabel et al, 2002), names of faults from Roetzel (1996),Lenhardt et al (2007) andNehyba et al (2012).…”

Chromium-rich illite/smectite in the basal Balinka Conglomerate of the Upper Carboniferous-Permian Boskovice Basin (Bohemian Massif)

“…Variable values of the chemical index of alteration (CIA; Nesbitt and Young, 1984) for the matrix of the Balinka Conglomerate (Houzar et al, 2013;Buriánek et al, 2020;Hrdličková et al, 2020) from 33 to 58 indicate the rapid denudation by fluvial erosion rather than a variation in chemical weathering. The poorly sorted, coarse-grained Balinka Conglomerate is interpreted as the products of the mass flow in the alluvial fans (Nehyba et al, 2012).…”