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Integrated biostratigraphy and carbon isotope stratigraphy of the Upper Jurassic shallow water carbonates of the High-Tatric Unit (Mały Giewont area, Western Tatra Mountains, Poland)

Pszczółkowski A., Grabowski J., Wilamowski A.

Geological Quarterly

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2016

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Vol. 60, No. 4

893--918

EN

New biostratigraphical and carbon isotope data are presented for the Upper Jurassic limestones of the Raptawicka Turnia Limestone Formation (High Tatric unit, Western Tatra Mountains, Poland) from the Mały Giewont area. The Kimmeridgian, lower Tithonian and lower part of the upper Tithonian have been identified on the basis of calcareous dinocysts and calpionellids. Eight microfossil biozones are distinguished: acme Fibrata, acme Parvula, Moluccana, Borzai, Tithonica acme Pulla(?), Malmica, Chitinoidella and Crassicollaria (pars). The Kimmeridgian/Tithonian boundary is indicated at the top of the Borzai Zone 76 m above the base of the Raptawicka Turnia Limestone Formation. The microfossil stratigraphy suggests the late Early Kimmeridgian age (acme Parvula Zone) of the ammonites described by Passendorfer (1928). The taxon Taramelliceras ex gr. compsum found 14 m above those ammonites is Late Kimmeridgian in age. Seven microfacies types (MF) are identified in the Upper Jurassic limestones of the Mały Giewont area. The Bositra-Saccocomidae MF occurs across the Lower-Upper Kimmeridgian boundary. The planktonic and benthic foraminifera occur in the Upper Jurassic deposits of the Raptawicka Turnia Limestone Formation. The genera Lenticulina Lamarck and Spirillina Ehrenberg are common in the Kimmeridgian and Tithonian limestones. The palaeobathymetric evolution of the Kimmeridgian-Tithonian deposition recorded in the Mały Giewont sections reveals: the transgressive episode at the Lower/Upper Kimmeridgian boundary interval, the transgression peak during the Early Tithonian (Malmica Zone) and gradual shallowing of the High-Tatric swell in the Late Tithonian. Integrated isotope stratigraphy and biostratigraphy enabled correlation with the pelagic section of the Sub-Tatric succession in the Długa Valley section. The middle part of the Raptawicka Turnia Limestone Formation (Upper Kimmeridgian) might be correlated with the upper part of the Czajakowa Radiolarite Formation (red radiolarites) and Czorsztyn Formation in the Długa Valley section. The upper part of the Raptawicka Turnia Limestone Formation of Early Tithonian age corresponds mostly to the Jasenina Formation. The overall similarity of the δ13C decreasing values recorded in the Kimmeridgian–earliest Tithonian interval of the Mały Giewont (this study) and Długa Valley sections indicates that the generally shallow-water deposits of the Raptawicka Turnia Limestone Formation accumulated below the zone influenced by changes in the composition of marine water caused, for instance, by intense rainfalls.

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Brachiopods and stratigraphy of the Upper Devonian (Frasnian) succession of the Radlin Syncline (Holy Cross Mountains, Poland)

Baliński A., Racki G., Halamski A. T.

Acta Geologica Polonica

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2016

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Vol. 66, no. 2

125--174

EN

The lower part of the Frasnian succession in the Radlin Syncline (Kielce–Łagów Synclinorium, southern region of the Holy Cross Mountains), in the two studied successions: Józefka at Górno and (for the first time) Radlin, consists of the rhythmic marly Szydłówek Beds, the fossil-rich limestones of the Wietrznia Beds (locally) and the atypically developed, calcareous Kostomłoty Beds. The carbon isotope chemostratigraphic pattern overall corresponds well to the global Early–Middle Frasnian biogeochemical perturbation, even if the major punctata positive excursion is only fragmentarily recorded in the Kostomłoty intrashelf basin. Two brachiopod assemblages are abundantly represented in both sections: the Phlogoiderhynchus polonicus Assemblage, typical of the Szydłówek Beds, and the Biernatella lentiformis Assemblage, limited to the middle part of the Wietrznia Beds. Both are highly dominated by the index species. Twenty nine lower Frasnian brachiopod species (Craniida – 1 species, Strophomenida – 1, Productida – 2, Protorthida – 1, Orthida – 5, Pentamerida – 1, Rhynchonellida – 4, Atrypida – 4, Athyridida – 3, Spiriferida – 4, Spiriferinida – 3) are described from the Szydłówek and Wietrznia Beds. Seven new species are introduced: Skenidioides cretus Halamski sp. nov., Biernatium minus Baliński sp. nov., Monelasmina montisjosephi Baliński sp. nov., Atryparia (Costatrypa) agricolae Halamski and Baliński sp. nov., Davidsonia enmerkaris Halamski sp. nov., Leptathyris gornensis Baliński sp. nov., and Echinocoelia parva Baliński sp. nov. Davidsonia enmerkaris Halamski sp. nov. is intermediate between Davidsonia Bouchard-Chantereaux, 1849 and Rugodavidsonia Copper, 1996 and is the youngest known representative of the suborder Davidsonioidea Copper, 1996. Skenidioides cretus Halamski sp. nov. is the last representative of the genus. Statistical investigation of a large sample of Spinatrypina (Exatrypa) explanata did not confirm the existence of two dimorphic forms, coarse- and fine-ribbed. The high-diversity Biernatella lentiformis Assemblage is quite dissimilar to coeval brachiopod assemblages described heretofore from the Holy Cross Mountains region. It is interpreted as consisting of mostly parautochthonous dwellers of deep-slope muddy habitats and a local, occasionally storm-agitated, intra-basin brachiopod-crinoid-coral shoal. The fauna was adapted probably to cooler and nutrient-poor waters during an initial phase of the severe carbon cycle perturbation.

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A revised inoceramid biozonation for the Upper Cretaceous based on high-resolution carbon isotope stratigraphy in northwestern Hokkaido, Japan

Hayakawa T., Hirano H.

Acta Geologica Polonica

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2013

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Vol. 63, no. 2

239--263

EN

Biostratigraphic correlations of inoceramid bivalves between the North Pacific and Euramerican provinces have been difficult because the inoceramid biostratigraphy of the Japanese strata has been based on endemic species of the northwest Pacific. In this study, carbon stable isotope fluctuations of terrestrial organic matter are assembled for the Upper Cretaceous Yezo Group in the Haboro and Obira areas, Hokkaido, Japan, in order to revise the chronology of the inoceramid biozonation in Japan. The carbon isotope curves are correlated with those of marine carbonates in English and German sections with the aid of age-diagnostic taxa. According to the correlations of the carbon isotope curves, 11 isotope events are recognised in the sections studied. As a result of these correlations, the chronology of the inoceramid biozones of the Northwest Pacific has been considerably revised. The revised inoceramid biozones suggest that the timing of the origination and extinction of the inoceramids in the North Pacific biotic province is different from the stage/substage boundaries defined by inoceramids, as used in Europe and North America.

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Carbon isotope stratigraphy of the basal Zechstein (Lopingian) strata in Northern Poland and its global correlation

Peryt T. M., Durakiewicz T., Kotarba M. J., Oszczepalski S., Peryt D.

Geological Quarterly

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2012

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Vol. 56, No 2

285-298

EN

The Kupferschiefer (T1) records a period of basin-wide euxinic conditions, and is thus considered an excellent time-marker in the Zechstein (Lopingian) basin. Previous studies indicated that both the Kupferschiefer and Marl Slate and the overlying Zechstein Limestone (Magnesian Limestone) show remarkable changes in carbon isotopic composition towards higher 131313131313