Correlation of the Middle and Upper Permian marine and terrestrial sedimentary sequences in Polish, German, and USA Western Interior Basins with reference to global time markers

Here we discuss the duration and position of Upper Rotliegend and Zechstein stratigraphic units in relation to the absolute time scale, and reinterpret a carbon isotope (δ13C) global event recorded from Late Permian (Lopingian/Guadalupian) marine deposits. Based on δ13C isotope correlation (chemostratigraphy) and of climatic evidence related to the end-Guadalupian global marine and terrestrial crisis, the Guadalupian/Lopingian boundary is proposed as the boundary between both the European Upper Rotliegend (URII)/Zechstein sediments and the parallel south-west USA Ochoan/Bell Canyon Formation units. The Zechstein deposition was strongly influenced by climatic oscillations, and the marine ingressions recorded in the North German Basin and North American Delaware Basin are presumed to have resulted from the same eustatic sea-level changes in western and northern coasts of the Northern Pangaea Supercontinent. Existing constraints on the age of the Upper Rotliegend II (UR II) deposits are imposed by the uncertainty of the chronostratigraphic boundary of the Kupferschiefer and by a time marker that is Illawarra, the boundary of the reversed polarity megachron (Kiaman) and mixed polarity megachron. Three options (A, B, C) have been discussed, which are connected with a time span comprising deposition of the UR II rocks, assuming that the time span needed for the Dethlingen/Lower Noteć formations and Hannover/Upper Noteć formations is about 6 myr. The time left for the deposition of the Parchim/Lower Drawa, Mirow/Upper Drawa deposits and the time hidden in the erosional gaps and hiatuses range from 1.6 myr to 4 myr or even 8 myr. These were based on the time interval related to the Kiaman Reversed Polarity megachron, which can contain more transient normal polarity zones than currently accepted. The presence and absolute dating of all such magnetozones is difficult to determine because they are represented in continental strata characterized by numerous, poorly time-constrained erosional gaps. The proposed option C is provisionally integrated with magnetostratigraphic results and shows an alternative stratigraphical scheme for the Upper Rotliegend. This alternate Upper Rotliegend stratigraphy helps correlate rocks (deposited in dry arid climatic conditions) in the lower part of the Upper Rotliegend II of the Southern Permian Basin (Havel and Drawa subgroups) with similar rocks in the Delaware Basin (attributed to formations within the Leonardian Regional Series).