ASGP (2015), vol. 85: 557–586

KEY ASPECTS OF THE STRATIGRAPHY OF THE UPPER SILESIAN MIDDLE KEUPER, SOUTHERN POLAND

Joachim SZULC (1), Grzegorz RACKI (2, 3) & Karol JEWUŁA (1)

1) Institute of Geological Sciences, Jagiellonian University, Oleandry 2a, 30-063 Kraków, Poland; e-mail: joachim.szulc at uj.edu.pl
2) Institute of Geological Sciences, Polish Academy of Sciences, Research Centre in Kraków, Senacka 1, Kraków, Poland
3) Faculty of Earth Sciences, University of Silesia, Będzińska 60, 41 200 Sosnowiec, Poland; e-mail: grzegorz.racki at us.edu.pl

Szulc, J., Racki, G. & Jewuła, K., 2015. Key aspects of the stratigraphy of the Upper Silesian middle Keuper, southern Poland. Annales Societatis Geologorum Poloniae, 85: 557–586.

Abstract: The stratigraphy of the Upper Silesian Keuper, a continental, mudstone-dominated succession is poorly known, although the already renowned, newly discovered vertebrate localities highlight the growing demand for a more precise intra-regional correlation and an appropriate stratigraphic reference framework. A major lithostratigraphic unit, preliminarily proposed for the middle Keuper (i.e., above the Schilfsandstein; Stuttgart Formation in “Stratigraphische Tabelle von Deutschland”, 2002) by Szulc and Racki (2015; Przegląd Geologiczny, 63: 103– 113), is described in detail. The redefined Grabowa Variegated Mudstone-Carbonate Formation, the unit previously based on inaccurately presented information, includes the Upper Gypsum Beds and the Steinmergel-keuper in the traditional scheme from Germany (= Weser and Arnstadt formations). Three members are formally defined: the Ozimek (Mudstone-Evaporite) Member, the Patoka (Marly Mudstone-Sandstone) Member and the Woźniki (Limestone) Member. Two significant bone-bearing horizons (Krasiejów and Lisowice) are placed within the Patoka Mbr. The formation thickness in a composite, regional reference section of the Upper Silesian Keuper, based on the new Woźniki K1 and Patoka 1 well profiles, is approximately 215 m thick. The Grabowa Fm generally correlates with the Norian stage, with the base located in the undefined upper Carnian, and is topped by a major, erosive disconformity and sedimentary sequence boundary, near the Norian-Rhaetian boundary. However, hiatuses in the Silesian middle Keuper succession are located and paired with a cannibalistic type of sand-mud flat deposition, largely controlled by Early Cimmerian movements of tectonic blocks associated with the Kraków–Lubliniec shear zone.

Manuscript received 17 November 2015, accepted 15 December 2015