Andrea Svobodova

The Czech Academy of Sciences | AVCR

Notidanoides muensteri (Agassiz, 1843) is an extinct species of hexanchiform sharks, a typical element of Late Jurassic environments on the northern shelf of the Tethys Ocean. It is the only valid representative of genus Notidanoides. Isolated teeth and even articulated skeletons of this species were found in several European localities, mainly in...

Geology is a subject of low interest for many pupils and teachers. The present study aims at examining the organizational conditions for geology education using the model of the Czech Republic and Slovakia, drawing from the national curricula. The study discusses the possible reasons for the unpopularity of the field worldwide and proposes general...

This study presents the Lower/Middle Coniacian benthic and nektonic assemblages from the Březno u Loun, Bohemian Cretaceous Basin (BCB, Central Europe) and their stratigraphical and palaeoenvironmental implications. The locality is characterized by exceptional preservation of macrofossils (often including original aragonite shells). A relatively we...

In several bio – and magnetostratigraphically well-calibrated sections studied, especially in the Carpathian-Alpine system (and some additional sections in the Tethyan Realm), a very slight carbon isotopic negative excursion just at the J/K boundary (sensu base of the Alpina Subzone within the Calpionella Zone) shows an almost identical trend.

This is an account of finds of stratigraphically useful calcareous nannofossils and the magnetostratigraphy of the Jurassic-Cretaceous boundary interval of the eastern Crimean peninsula (southern Ukraine). We compare these new complementary results with those presented by our team in earlier publications. A missing interval in the Crimean sequence...

Anomalous early occurrence of Notidanoides muensteri in Lower Oxfordian of Brno-Hády, Czechia.

The Early Turonian interval represents a unique confluence of climatic and oceanographic conditions including peak surface temperatures, high greenhouse-gas concentrations and maximum Phanerozoic sea level. The susceptibility of this climate mode to astronomical insolation forcing remains poorly understood partly due to a limited time control and u...

Supporting information includes a detailed well-log correlation of boreholes in the western depocenter of Bohemian Cretaceous Basin (Figures S1 – S6; uploaded separately), geochemistry and lithology of the reference borehole 4523-A (Figures S7 and S8), spectral estimates for a resistivity log of borehole J-719 670 (Fig. S9), results of the TimeOpt...

In part 1 of this work we discussed the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on prevailing practical methods for correlation in that J/K interval, traditional usage and the consensus over the best boundary markers that had developed in the last forty years. This consensus has developed f...

Abstract. In part 1 of this work we discussed the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on prevailing practical methods for correlation in that J/K interval, traditional usage and the consensus over the best boundary markers that had developed in the last forty years. This consensus has d...

Here we assess the evidence for the placing of magnetic and fossil biozonal boundaries in Upper Tithonian to lower Berriasian (Jurassic-Cretaceous boundary) sedimentary rocks on the Black Sea coast south of Theodosia (Ukraine): that is, in magnetozones M19n to M17r. We consider our earlier-published results from these sections in relation to the co...

Here in the first part of this publication we discuss the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on the established methods for correlation in the Tithonian/Berriasian interval. This will be followed, in the second part, by an account of the stratigraphic evidence that justifies the locali...

Abstract: This work summarises the results of ten years of study of the palaeomagnetism and biostratigraphy of Tithonian–Berriasian profiles in the middle Vocontian Basin: at Le Chouet, Le Ravin de Font de Saint Bertrand, Charens, Belvedere (Haute Beaume) and Tré Maroua. This study has thus focussed on the “Calcaires Blancs vocontiens”, a predomina...

Geology is a science with a highly interdisciplinary character. Thus, in education it is ideal to provide education in a form integrated with the other branches of natural sciences under the subject of Science or Natural Sciences. However, most European countries prefer separate teaching of the individual educational fields and subsume geology with...

The classical locality of Svinary in the eastern Bohemian Cretaceous Basin is the site of new biostratigraphic investigations. Besides some scarce macrofossil evidence, bulk sediment samples were processed to retrieve micropalaeontological assemblages, and calcareous nannofossil smear slides were analysed. The studied material provided calcareous n...

Since 2009 the Berriasian Working Group (ISCS, ICS) has been searching for the best sequence globally to represent the Tithonian/Berriasian (Jurassic/Cretaceous) boundary. To take this forward, it has made field assessments of more than sixty localities, documenting their sequences, fossil biotas and magnetostratigraphy. Only on such a sound factua...

A high-resolution multidisciplinary study of two profiles in the Kotouč Quarry at Štramberk was carried out to define the age and palaeoenvironmental setting of the peri-reefal Štramberk Limestone. Calpionellids of the Alpina and Ferasini subzones of the standard Calpionella Zone confirm an early Berriasian age for both studied sequences. The prese...

New calcareous nannofossil material has been obtained from the Dvuyakornaya Formation in Dvuyakornaya Bay, 2 km west of the well-studied Theodosia lighthouse cliffs (Bakhmutov et al. 2018). The section was previously studied by Platonov et al. (2014) for calpionellids. The sequence is predominantly one of mudstones, approaching 300 metres in thickn...

Microfacies and high resolution studies at the Kurovice quarry (Czech Republic, Outer Western Carpathians) on calpionellids, calcareous and non-calcareous dinoflagellate cysts, sporomorphs and calcareous nannofossils, aligned with paleomagnetism, allow construction of a detailed stratigraphy and paleoenvironmental interpretation across the Jurassic...

An integrated magneto- and biostratigraphic study of the Jurassic-Cretaceous (J-K) boundary section at Kurovice, Czech Republic was carried out. The acquired paleomagnetic data showed dual polarity characteristic remanent magnetization (ChRM) with counter-clockwise rotation direction. Rock magnetic data indicated magnetite as the principal carrier...

Palaeo- and rock-magnetic investigations of the St Bertrand’s Spring (Le Ravin de Font de St Bertrand) locality in France were carried out in order to contribute to, and improve, the stratigraphy of the Jurassic-Cretaceous boundary interval. Magnetic susceptibility shows slightly diamagnetic behaviour in the lowermost part of the profile and an inc...

A well preserved Upper Tithonian–Lower Berriasian Strapkova sequence of hemipelagic limestones improves our understanding of environmental changes occurring at the Jurassic/Cretaceous boundary in the Western Carpathians. Three dinoflagellate and four calpionellid zones have been recognized in the section. The onset of the Alpina Subzone of the stan...

We obtained material from the Puerto Escano section (southern Spain) to study the Jurassic/Cretaceous (J/K) boundary interval. The same samples had already been processed for magnetostratigraphic studies and biostratigraphic zonation based on calpionellids and ammonites (Pruner et al. 2010), but not for calcareous nannofossils. The aim of this stud...

The Upper Turonian – actually the uppermost Turonian strata in the Èeøovka Hill (Jièín) have newly been confirmed by the occurrence of calcareous nannofossils identified in two samples of sediments collected at two new random outcrops in 2012–2015. They exposed marls to clayey marlstones of the Xab, Prionocyclus germari ammonite Zone. These rocks a...

The re-discovered original specimen of the texanitid ammonite Texanites pseudotexanus, described as Mortoniceras texanus by Hibsch (1929) and illustrated as Mortoniceras pseudotexanus by Storm (1931), as well as three fragments of Paratexanites serratomarginatus documented (and one illustrated) by Fritsch (in Fritsch & Schlönbach 1872) as Ammonites...