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Volume 55 (2021): Issue 1-2 (December 2021)

Volume 54 (2020): Issue 1-2 (December 2020)

Volume 53 (2019): Issue 1 (January 2019)

Volume 52 (2019): Issue 1-2 (January 2019)

Volume 51 (2017): Issue 1-2 (December 2017)

Volume 50 (2016): Issue 1-2 (December 2016)

Volume 49 (2015): Issue 1-2 (December 2015)

Volume 48 (2014): Issue 1-2 (December 2014)

Volume 47 (2013): Issue 1-2 (January 2013)

Volume 46 (2012): Issue 1-2 (December 2012)

Journal Details
Format
Journal
eISSN
1805-286X
First Published
20 Nov 2014
Publication timeframe
1 time per year
Languages
English

Search

Volume 55 (2021): Issue 1-2 (December 2021)

Journal Details
Format
Journal
eISSN
1805-286X
First Published
20 Nov 2014
Publication timeframe
1 time per year
Languages
English

Search

3 Articles
Open Access

3D Chemometric Model Simulating the Acitheca Polymorpha Frond: Implications for Reconstructing Carboniferous Ferns (Marattiales, Canada)

Published Online: 07 Mar 2022
Page range: 1 - 21

Abstract

Abstract

Reported are results of an initial approximate imitation of a Carboniferous fern frond, i.e., marattialean Acitheca polymorpha (Schimper), Middle Pennsylvanian Sydney Coalfield, Canada. The simulation experiment is based on the analysis of 14 infrared spectra obtained by means of Fourier Transform Infrared spectroscopy from four detached fragments of sterile polymorphic penultimate-pinna compressions. The calculated relative, semi-quantitative, chemical data from the infrared spectra are the input for principal component analysis deriving a 3D (three-dimensional) chemometric model. To interpret it, the four specimens are placed in hypothetical-frond positions simulating a tripinnate frond, based on diminishing penultimate-rachial widths from 1-mm (distal) to 10-mm (proximal). Hypothetical conclusions include position-dependent chemistries, specifically that of opposing trends of aromaticity vs. aliphaticity in pinnules-rachises. This, in turn, would suggest potential for (i) fern-frond reconstruction, and (ii) for determination of a most likely frond position of fragmentary specimens by “chemical classification”; the predictive aspect. However, further experimental refinement is necessary particularly based on larger frond segments to confirm or disconfirm the overall hypothetical results.

Keywords

  • Fossil fern
  • FTIR
  • chemical frond architecture
  • Carboniferous
Open Access

Source of K-Feldspars and Kaolinitization in Arkoses of West and Central Bohemian Continental Permo–Carboniferous

Published Online: 07 Mar 2022
Page range: 23 - 37

Abstract

Abstract

The examined K-feldspars in arkoses of the continental Upper Carboniferous – Lower Permian of the West and Central Bohemian basins originated in the whole bed sequence (Duckmantian to Autunian; 314.2–297.1 Ma) from one source, which were so-called mountain granites of the older intrusive complex (OIC) of the Krušné hory Mts, as confirmed by the X-ray and geochemical analyses. The presence of feldspar clasts from other granitoids (Merklín and Louny massifs) was found only in the straight transgreding basal Carboniferous rocks. While other arkoses underwent synsedimentary and/or post-sedimentary kaolinization, in the deposits of Kaznějov and Horní Bříza (Nýřany Member of the Kladno Formation) pre-sedimentary kaolinization (sedimentation of sandstones and conglomerates with kaolinitic cement) occurred.

Keywords

  • Permo-Carboniferous
  • West and Central Bohemian basins
  • arkoses
  • Karlovy Vary Massif
  • K-feldspar
  • triclinicity
  • trace elements
  • kaolinization
Open Access

First Record of Podichnus in Byronid Shell from the Lower Devonian (Pragian) of the Prague Basin, Czechia

Published Online: 07 Mar 2022
Page range: 39 - 44

Abstract

Abstract

Brachiopod etching trace Podichnus, typically with centrifugally arranged clusters of holes or slits, has hitherto been known only in calcium carbonate substrates. The similar etching trace is newly described on calcium phosphate substrate. The trace Podichnus isp. in a wall of a phosphatic byronid test was observed in the lower Devonian Vinařice Limestone (Pragian) in the Koněprusy area of the Prague Basin in the Barrandian area, the Czech Republic. The trace is smaller that majority of described species of this fixichnia, and displays a smooth central disc surrounded by two circlets of holes or pits. Some holes penetrate through wall of byronid test without any biotic response of a byronid. The maker of Podichnus isp. is uknown but among the associated fossils are eligible candidates including rhynchonellids, orthids and terebratulids. It is rare direct evidence of etching activity of the pedicle in the Lower Palaeozoic and the first finding of Podichnus in the Devonian in the Prague Basin. The emended diagnosis of the ichnogenus is presented herein.

Keywords

  • byronid
  • brachiopod
  • calcium phosphate
  • fixichnia
  • Devonian
  • Barrandian area
  • Prague Basin
3 Articles
Open Access

3D Chemometric Model Simulating the Acitheca Polymorpha Frond: Implications for Reconstructing Carboniferous Ferns (Marattiales, Canada)

Published Online: 07 Mar 2022
Page range: 1 - 21

Abstract

Abstract

Reported are results of an initial approximate imitation of a Carboniferous fern frond, i.e., marattialean Acitheca polymorpha (Schimper), Middle Pennsylvanian Sydney Coalfield, Canada. The simulation experiment is based on the analysis of 14 infrared spectra obtained by means of Fourier Transform Infrared spectroscopy from four detached fragments of sterile polymorphic penultimate-pinna compressions. The calculated relative, semi-quantitative, chemical data from the infrared spectra are the input for principal component analysis deriving a 3D (three-dimensional) chemometric model. To interpret it, the four specimens are placed in hypothetical-frond positions simulating a tripinnate frond, based on diminishing penultimate-rachial widths from 1-mm (distal) to 10-mm (proximal). Hypothetical conclusions include position-dependent chemistries, specifically that of opposing trends of aromaticity vs. aliphaticity in pinnules-rachises. This, in turn, would suggest potential for (i) fern-frond reconstruction, and (ii) for determination of a most likely frond position of fragmentary specimens by “chemical classification”; the predictive aspect. However, further experimental refinement is necessary particularly based on larger frond segments to confirm or disconfirm the overall hypothetical results.

Keywords

  • Fossil fern
  • FTIR
  • chemical frond architecture
  • Carboniferous
Open Access

Source of K-Feldspars and Kaolinitization in Arkoses of West and Central Bohemian Continental Permo–Carboniferous

Published Online: 07 Mar 2022
Page range: 23 - 37

Abstract

Abstract

The examined K-feldspars in arkoses of the continental Upper Carboniferous – Lower Permian of the West and Central Bohemian basins originated in the whole bed sequence (Duckmantian to Autunian; 314.2–297.1 Ma) from one source, which were so-called mountain granites of the older intrusive complex (OIC) of the Krušné hory Mts, as confirmed by the X-ray and geochemical analyses. The presence of feldspar clasts from other granitoids (Merklín and Louny massifs) was found only in the straight transgreding basal Carboniferous rocks. While other arkoses underwent synsedimentary and/or post-sedimentary kaolinization, in the deposits of Kaznějov and Horní Bříza (Nýřany Member of the Kladno Formation) pre-sedimentary kaolinization (sedimentation of sandstones and conglomerates with kaolinitic cement) occurred.

Keywords

  • Permo-Carboniferous
  • West and Central Bohemian basins
  • arkoses
  • Karlovy Vary Massif
  • K-feldspar
  • triclinicity
  • trace elements
  • kaolinization
Open Access

First Record of Podichnus in Byronid Shell from the Lower Devonian (Pragian) of the Prague Basin, Czechia

Published Online: 07 Mar 2022
Page range: 39 - 44

Abstract

Abstract

Brachiopod etching trace Podichnus, typically with centrifugally arranged clusters of holes or slits, has hitherto been known only in calcium carbonate substrates. The similar etching trace is newly described on calcium phosphate substrate. The trace Podichnus isp. in a wall of a phosphatic byronid test was observed in the lower Devonian Vinařice Limestone (Pragian) in the Koněprusy area of the Prague Basin in the Barrandian area, the Czech Republic. The trace is smaller that majority of described species of this fixichnia, and displays a smooth central disc surrounded by two circlets of holes or pits. Some holes penetrate through wall of byronid test without any biotic response of a byronid. The maker of Podichnus isp. is uknown but among the associated fossils are eligible candidates including rhynchonellids, orthids and terebratulids. It is rare direct evidence of etching activity of the pedicle in the Lower Palaeozoic and the first finding of Podichnus in the Devonian in the Prague Basin. The emended diagnosis of the ichnogenus is presented herein.

Keywords

  • byronid
  • brachiopod
  • calcium phosphate
  • fixichnia
  • Devonian
  • Barrandian area
  • Prague Basin

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