Browsing by Author "Tomanová Petrová, Pavla"

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    Early Badenian Transgression On The Outer Flank Of Western Carpathian Foredeep, Hluchov Area, Czech Republic
    (Polish Geological Soc, 2014-01-01) Hladilová, Šárka; Nehyba, Slavomír; Zagoršek, Kamil; Tomanová Petrová, Pavla; Bitner, Maria Aleksandra; Demeny, Attila
    This multidisciplinary study, based on borehole cores from the Hluchov area in Czech Republic, documents an early Badenian marine transgression on the outer flank of the Western Carpathian Foredeep. The shallow-marine deposits represent coastal transgression over a terrestrial topography of weathered pre-Cenozoic bedrock. The lower facies association (FA1) consists of siliciclastic sediment derived from local substrate erosion. Facies indicate a wave-dominated environment with unstable bottom, variable rate of sediment supply and an incremental rise of relative sea level. The upper facies association (FA2) consists of carbonates indicating a major landward shift of shoreline, decline in siliciclastic input and further sea-level rise. The succession represents a transgressive to highstand systems tract. The maximum flooding surface, ca. 1 m above the FA1/FA2 boundary, is signified by an anomalous decrease in K and Th, an increased Th/K ratio and highest U concentration. The heavy-mineral assemblages in FA1 confirm local sediment provenance, whereas those in FA2 indicate broader sediment derivation, including volcanic component from contemporaneous rhyolitic to rhyodacitic eruptions. The deposits contain a wide range of marine fauna, with the foraminifers and molluscs indicating an early Badenian age. Molluscs, bryozoans and echinoderms indicate a normal-salinity environment with a decreasing hydraulic energy. Foraminifers indicate salinity fluctuations in the lowest part of the succession. The isotopic composition of mollusc shells shows marked inter-species differences and a general negative shift in the delta C-13 and delta O-18 values, indicating diagenetic alteration. The impact of diagenetic processes appears to have been controlled by sedimentary facies. The highly negative delta C-13 and delta C-18 values correspond to sediment layers with the highest Th/K ratios and hence low clay content. Sediment permeability was thus probably crucial in controlling the differential circulation and impact of diagenetic fluids.
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    Střednopleistocenní sesuv na svazích Drahanské vrchoviny u Viničných Šumic
    (Masaryk University,Faculty of Science,Department of Geological Sciences, 2019-01-01) Tomanová Petrová, Pavla; Krejčí, Oldřich; Doláková, Nela; Gilíková, Helena; Hladilová, Šárka; Zágoršek, Kamil
    In 2018 an excavation of 20 × 20 m large and up to 5 m thick calcareous clays of the Langhian age was found. Rich and diversified assemblages of foraminifers with species Orbulina suturalis Brön. and Martinotiella karreri (Cush.) indicate early Badenian (in sense of the Central Paratethys regional stratigraphy) age of the sediments, zone M5bsensu Berggren et al. (1995). Variously deformed lenses and layers of fine-grained sand with several blocks of white calcareous silts and with two layers of clayey sediments with pebbles were found. The identified outcrop is part of a largelandslide situated at the western margin of the Carpathian Foredeep. Samples determining the age of the landslide movements were taken from Badenian clays and from slope sediments with pebbles for study of palynomorphs. Very rich and diversified fauna was described mainly from the fine-grained sand creating layers in calcareous clays. The assemblage contained tests of foraminifers, spines of the echinoids, fragments of sponge spicules, rich fragments of molluscs and zoarias of bryozoas, worms-Ditrupa cornea (Linnaeus, 1758), Serpula sp., ?Serpulidae indet., fragments of brachiopods, arthropods, coral, ostracods, teleostei etc. The findings from the Badenian and Quaternary periods were mixed by slope movements. Large landslide in the Middle Pleistocene was the terminal gravity proces in the area of Viničné Šumice.