New occurrences of Paseky Shale near Podlesí NW of Příbram and microfossils from the Nové Podlesí locality (Cambrian, Holšiny-Hořice Formation, Příbram-Jince Basin)

 

Tomáš Vorel, Vojtěch Kovář

Geoscience Research Reports 56, 2023, pages 82–88
Map sheets: Březnice (22-12)

Full text (PDF, 10.04 MB)

Published online: 2024-02-05

Export to RIS

 

Abstract

Previously unrecorded occurrences of the Paseky Shale were found in the course of geological mapping at three localities NW of Příbram near Podlesí (Fig. 1). This shale makes a part of the Cambrian Series 2, Holšiny-Hořice Formation in the Příbram-Jince Basin. The shale was documented ca. 250 m S and about 80 m NE of the Malá Dubová hora summit as abundant loose rock fragments (Fig. 2) and soil skeleton (Fig. 3), respectively. An outcrop of the Paseky Shale was found in a small quarry near Nové Podlesí (Figs 4 to 9).

The Paseky Shale has a significant position within the geological record of the Barrandian area as it hosts the oldest macrofossil fauna in the Czech Republic, most notably the aglaspid-like arthropod Kodymirus vagans Chlupáč & Havlíček 1965 (Chlupáč – Havlíček 1965, Lamsdell et al. 2013).

A microfossil analyses of samples from the quarry near Nové Podlesí has been carried out. The microfossils are relatively sparse and generally rather poorly preserved. The assemblage consists mostly of filaments belonging to the genus Siphonophycus Schopf 1968, emend. Knoll et al. 1991 (Fig. 10 A, D, E, F) ranging from ca. 8 to 50 µm in width. Less common are representatives of Leiosphaeridia minutissima Naumova 1949, emend. Jankauskas in Jankauskas et al. 1989 (Fig. 10 B, C). No other acritarchs were found. Residues further include poorly identifiable fragments of organic-walled microfossils, most likely representing degraded filaments (Fig. 10 G).

The studied assemblage is consistent with findings from other localities of the Paseky Shale. However, further relatively rarer components of the microfossil assemblages known from other localities (see Fatka – Konzalová 1995, Kovář – Fatka 2023) are missing. This is most likely due to the low abundance and generally poor preservation of the microfossils at the locality. The general absence of a more diversified acritarch assemblage corresponds to an atypical, restricted marine environment, presumably represented by a lagoonal setting (see Fatka – Konzalová 1995).


 

References

Butterfield, N. J. – Harvey, T. H. P. (2012): Small carbonaceous fossils (SCFs): A new measure of early Paleozoic paleobiology. – Geology 40 (1), 71–74.

Fatka, O. (1999): Organic walled microfossils of the Barrandian area: a review. – J. Czech geol. Soc. 44 (1–2), 31–42.

Fatka, O. – Konzalová, M. (1995): Microfossils of the Paseky Shale (Lower Cambrian, Czech Republic). – J. Czech geol. Soc. 40 (4), 55–66.

Fatka, O. – Szabad, M. (2014): Cambrian biostratigraphy in the Příbram-Jince Basin (Barrandian area, Czech Republic). – Bull. Geosci. 89 (2), 411–427.

Fatka, O. – Valent, M. (2019): A review of recorded taxa Cambrian hyoliths of the Příbram-Jince Basin (Barrandian area, the Czech Republic): A review of recorded taxa. – Foss. Imprint 75 (1), 128–140.

Havlíček, V. (1950): Zpráva o geologickém mapování na Jinecku. – Věst. St. geol. Úst. Čs. Republ. 25, 98–103.

Havlíček, V. (1971): Stratigraphy of the Cambrian of Central Bohemia. – Sbor. geol. Věd, Geol. 20, 7–52.

Chlupáč, I. (1995): Lower Cambrian arthropods from the Paseky Shale (Barrandian area, Czech Republic). – J. Czech geol. Soc. 40 (4), 9–36.

Chlupáč, I. - Havlíček, V. (1965): Kodymirus n. g.,a new aglaspid merostome of the Cambrian of Bohemia. - Sbor. geol. Věd, Paleont. 6, 7-20.

Chlupáč, I. – Kraft, J. – Kraft, P. (1995): Geology of fossil sites with the oldest Bohemian fauna (Lower Cambrian, Barrandian area). – J. Czech geol. Soc. 40 (4), 1–8.

Jankauskas, T. V. – Mikhailova, N. S. – Hermann, T. N., ed. (1989): Mikrofossilii Dokembriya SSSR. – 190 str. Nauka. Leningrad.

Kettner, R. (1917). O jineckých vrstvách na Příbramsku. – Sbor. čes. Spol. zeměvěd. 23, 32–40.

Knoll, A. H. – Swett, K. – Mark, J. (1991): Paleobiology of a Neoproterozoic tidal flat/lagoonal complex: the Draken Conglomerate Formation, Spitsbergen. – J. Paleont. 65 (4), 531–570.

Kovář, V. – Fatka, O. (2023): Organic-walled microfossils from the restricted marine environment of the Paseky Shale (Barrandian area, Czech Republic). In: Eble, C. – O’Keefe, J., ed.: A Joint Meeting of the 55th Annual Meeting of AASP – The Palynological Society and Meeting of the CIMP – Commission Internationale de la Microflore du Paléozoique Subcommissions. – Program and Abstracts. Lexington.

Lamsdell, J. C. – Stein, M. – Selden, P. A. (2013): Kodymirus and the case for convergence of raptorial appendages in Cambrian arthropods. – Naturwissenschaften 100 (9), 811–825.

Mašek, J. - Havlíček, V. - Hazdrová, M. - Líbalová, J. - Straka, J. - Šalanský, K. - Vlašímský, P. (1986):Základní geologická mapa ČR v měřítku 1 : 25 000,list 22-122 Bohutín, autorský rukopis. - MS Čes. geol. služba. Praha.

Mašek, J. – Havlíček, V. – Straka, J. (1990): Soubor geologických a účelových map – Geologická mapa ČR v měřítku 1 : 50 000, list 22-12 Březnice. – Ústř. úst. geol. Praha.

Mikuláš, R. (1995): Trace fossils from the Paseky Shale (Early Cambrian, Czech Republic). – J. Czech geol. Soc. 40 (4), 37–54.

Naumova, S. N. (1949): Spory nizhnego kembriya. – Izv. Akad. Nauk SSSR, Ser. geol. 4, 49–56.

Riding, J. (2021): A guide to preparation protocols in palynology. – Palynology 45 (S1), 1–110.

Schopf, J. W. (1968): Microflora of the Bitter Springs Formation, late Precambrian, central Australia. – J. Paleont. 42 (3), 651–688.

Steiner, M. – Fatka, O. (1996): Lower Cambrian tubular micro to macrofossils from the Paseky Shale of the Barrandian area (Czech Republic). – Paläont. Z. 70 (3–4), 275–299.

Syahputra, R. – Žák, J. – Nance, R. D. (2022): Cambrian sedimentary basins of northern Gondwana as geodynamic markers of incipient opening of the Rheic Ocean. – Gondwana Res. 105, 492–513.