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Joachim Szulc - One of the best experts on this subject based on the ideXlab platform.
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key aspects of the stratigraphy of the upper silesian middle Keuper southern poland
Annales Societatis Geologorum Poloniae, 2015Co-Authors: Joachim Szulc, Grzegorz Racki, Karol JewulaAbstract: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 lithostrati- graphic 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 pre- viously 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 (Krasiejow 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 Krakow– Lubliniec shear zone.
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palynostratigraphy and palynofacies of the upper silesian Keuper southern poland
Annales Societatis Geologorum Poloniae, 2015Co-Authors: Anna Fijalkowskamader, Carmen Heunisch, Joachim SzulcAbstract:The results of the palynostratigraphical studies presented in this paper come from five boreholes Patoka 1, Czarny Las, Woźniki Śląskie K1, Kobylarz 1 and Poreba as well as from four outcrops at Lipie Śląskie, Patoka, Zawiercie and Poreba, in Upper Silesia (southern Poland). The palynostratigraphical zonation presented by Orlowska-Zwolinska (1983) for the epicontinental Upper Triassic of Poland was applied. The palynomorph spectra are marked by different preservation states, combined with the frequent occurrence of reworked specimens, probably even from Palaeozoic strata. The spore-pollen assemblage recognized in the “Chrzanow Formation” belongs to the early Carnian verrucata Subzone of the palynological longdonensis Zone. The spectrum from the Stuttgart Formation represents the Carnian astigmosus Zone. Spectra in the Patoka Marly Mudstone-Sandstone Member (Grabowa Mudstone-Carbonate Formation), with the Lisowice bone-bearing horizon, represent the middle and late Norian meyeriana b Subzone. The Rhaetian age of the bone-bearing succession in the Lisowice–Lipie Śląskie clay-pit suggested in the literature was not confirmed. The age of assemblages from the “Polomia Formation”, which overlies the Patoka Member, was not determined, owing to the poor state of miospore preservation. Moreover, three types of palynofacies were recognized as being characteristic for a fluvial channel (1), a flood plain (2), and lacustrine and playa environments (3) as well as for an undetermined milieu. Type 1 was found in the deposits of the Stuttgart Formation, the Patoka Member and the “Polomia Formation”, type 2 in the Patoka Member and the “Polomia Formation”, type 3 in the “Chrzanow Formation”, the Stuttgart Formation and the Patoka Member.
Adolf Seilacher - One of the best experts on this subject based on the ideXlab platform.
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swimming trace of a coelacanth fish from the lower Keuper of south west germany
Palaeontology, 2003Co-Authors: Theo Simon, Hans Hagdorn, Magnus Hagdorn, Adolf SeilacherAbstract:Parundichna schoelli igen. nov., isp. nov. from the Middle Triassic (Ladinian) Lower Keuper of Rot am See (Baden-Wurttemberg, Germany) consists of clusters of sigmoidal scratches symmetrically arranged in a plaited pattern. It is here interpreted as the swimming trace of a large coelacanth fish. In contrast to ichnospecies of Undichna there is no unpaired groove left by the tail fin. Instead, the sets of parallel scratches resulted from the pendulum motion of two pairs of appendages, the pectoral and pelvic fins, which acted in alternation, as in tetrapods. This strange mode of swimming is compared to films of modern Latimeria and to computer simulations; it probably corresponds to a particular foraging behaviour. The presence of fittingly-sized coelacanths is documented in coeval carbonates (Alberti-Bank) by disarticulated skeletal elements. Since the Lower Keuper represents a fluvial and estuarine facies of the receding Muschelkalk sea, we cannot be sure whether this trace was made in a marine or freshwater environment.
Theo Simon - One of the best experts on this subject based on the ideXlab platform.
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swimming trace of a coelacanth fish from the lower Keuper of south west germany
Palaeontology, 2003Co-Authors: Theo Simon, Hans Hagdorn, Magnus Hagdorn, Adolf SeilacherAbstract:Parundichna schoelli igen. nov., isp. nov. from the Middle Triassic (Ladinian) Lower Keuper of Rot am See (Baden-Wurttemberg, Germany) consists of clusters of sigmoidal scratches symmetrically arranged in a plaited pattern. It is here interpreted as the swimming trace of a large coelacanth fish. In contrast to ichnospecies of Undichna there is no unpaired groove left by the tail fin. Instead, the sets of parallel scratches resulted from the pendulum motion of two pairs of appendages, the pectoral and pelvic fins, which acted in alternation, as in tetrapods. This strange mode of swimming is compared to films of modern Latimeria and to computer simulations; it probably corresponds to a particular foraging behaviour. The presence of fittingly-sized coelacanths is documented in coeval carbonates (Alberti-Bank) by disarticulated skeletal elements. Since the Lower Keuper represents a fluvial and estuarine facies of the receding Muschelkalk sea, we cannot be sure whether this trace was made in a marine or freshwater environment.
Philippe Duringer - One of the best experts on this subject based on the ideXlab platform.
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sequence stratigraphy of middle triassic carbonates and terrigenous deposits muschelkalk and lower Keuper in the sw germanic basin maximum flooding versus maximum depth in intracratonic basins
Sedimentary Geology, 2003Co-Authors: A Vecsei, Philippe DuringerAbstract:Abstract We analyze the sequence stratigraphy of the Middle Muschelkalk to the Lower Keuper strata (Middle Triassic) in the SW Germanic Basin. The sequences are interpreted on the basis of a synthesis of facies in the neritic carbonates, terrigenous sediments and evaporites along a basin margin to center transect. Continental sediments (CS, lower Middle Muschelkalk) occur at the base of the Middle–Upper Muschelkalk sequence. Thick retrogradational marginal-marine sediments overlain by open-marine deposits (middle Middle Muschelkalk to lower Upper Muschelkalk) form the transgressive systems tract. In the basin center, only bathymetric criteria are available for recognition of this systems tract. The maximum flooding surface (mfs) at the basin margin differs in age from the maximum depth interval in the basin center. Maximum depth surfaces or intervals (mdi, new term) should be recognized in many deep basins where flooding is not recorded. The highstand systems tract (upper Upper Muschelkalk) is strongly progradational. The upper sequence boundary (Muschelkalk/Keuper boundary) is characterized by subaerial exposure at the basin margin and submarine erosion in most other sections. Along this boundary, the low paleo-relief resulted in a lack of coarse-grained clastic deposits. In the basin center, a strongly regressive succession (lower Lower Keuper) allows, possibly for the first time in an intracratonic basin, the distinction of an early or late lowstand systems tract (ELST or LLST). High-frequency, low-amplitude sea-level fluctuations resulted in parasequences in the open-marine Upper Muschelkalk, but in high-frequency sequences in the coastal plain sediments of the overlying parts of the Lower Keuper.
Francois Guillocheau - One of the best experts on this subject based on the ideXlab platform.
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three dimensional accommodation analysis of the Keuper of the paris basin discrimination between tectonics eustasy and sediment supply in the stratigraphic record
Marine and Petroleum Geology, 2002Co-Authors: Sylvie Bourquin, Francois Guillocheau, Cecile Robin, Jeanmichel GaulierAbstract:Abstract During the Keuper, the Paris Basin was an intracratonic sedimentary basin filled by continental deposits. Using paleo-environmental, isopach and paleo-altitude maps, we estimate the variations of accommodation rate at the scale of stratigraphic minor hemi-cycle (1–3 Ma). An analysis of the short- and long-wavelength accommodation variations allows us to assess the relative influence of tectonics, eustasy and sediment supply on the stratigraphic record. Our data suggest a pattern of subsidence along three trends: E–W in the Carnian, E–W to NNE–SSW in the Norian and NE–SW in the Norian–Rhaetian. During the Keuper, the Paris Basin accurately records the different phases of the opening of the Tethys Ocean associated with a rotation of the extension direction. The Norian cycle could thus reflect the intraplate stresses in a transitional period between the Triassic and the Liassic.
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Keuper stratigraphic cycles in the paris basin and comparison with cycles in other peritethyan basins german basin and bresse jura basin
Sedimentary Geology, 1996Co-Authors: Sylvie Bourquin, Francois GuillocheauAbstract:Abstract High-resolution sequence stratigraphy of the Keuper, Paris Basin, is used to establish correlations between the basin-centre evaporite series and the basin-margin clastics series. The high-resolution correlations show stratigraphic cycle geometries. The Keuper consists of five minor base-level cycles whth occur in the upper portion of the Scythian-Carnian major base-level cycle and the lower part of the Carnian-Liassic major base-level cycle. The maximum relative rate of subsidence for the base-level fall phase of the Scythian-Carnian major cycle occurs in the eastern part of the Paris Basin. During the base-level rise phase of the Carnian-Liassic major cycle, the area of highest rate of subsidence shifted westwards and northwards. This shift records the first occurrence of an independent Paris Basin which was no longer merely the western margin of the German Basin. Two phases of tectonic movement influenced evaporite sedimentation and sequence geometries by creating areas of subsidence where halite could accumulate. The second, within the ‘Marnes irisees superieures’, induced a general westward and northward tilt of the basin. Concurrent migration of depocentres to the west and north produced an intra-‘Marnes irisees superieures’ truncation. Comparison of the stratigraphic records of the Paris Basin and of other Triassic Peritethyan basins (German Basin, Bresse-Jura Basin and South-East Basin) reveals numerous similarities. The coastal onlap curve of the German Keuper (Aigner and Bachmann, 1992) exhibits many similarities with the sequence evolution of the Paris Basin. But the Triassic succession is more complete in the German Basin and more cycles are observed. The major difference between these two basins during the Keuper is that the ‘Marnes irisees inferieures’ minor base-level cycle does not occur in the German Basin. In the Bresse-Jura Basin, the major difference concerns the Lettenkohle. One minor base-level cycle is recorded in the Paris Basin while no cycle is observed in the Bresse-Jura Basin.
