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The Jurassic belemnites of northern Bohemia - stratigraphy, palaeobiogeography and possible isotope record
Geist, Jan
4 Abstract The work is based on a revision of collection from several scientific institutions from the Czech Republic and the Federal Republic of Saxony (National Museum in Prague, Chlupáč Museum of Earth History, Senckenberg Natural History Collections Dresden, etc.). The collection is based on samples published by Oskar Lenz and George Bruder from the second half of the 19th century. Both authors also processed the findings of other researchers (e.g. Cotta, Weisse). The belemnite rostra were systematically divided into four families, five genera and seven identifiable genera. One rostrum has not exactly been determined. The age of the samples was established to be the Middle and Upper Jurassic (Bajocian- Kimmeridgian). The length of the expected sedimentation in this area has been prolonged to the past (deeper to the Middle Jurassic), mainly due to the finding of the species Megateuthis gigantea Schlotheim, 1820. Earlier research (especially in the 20th century) assumed the extent of preserved carbonate rocks only in the Oxfordian and Kimmeridgian age, with a not much fossiliferous Callovian Brtníky Formation. The studied sedimentary rocks show a significant influence of Milankovich cycles with repeated alternation of carbonate and non- carbonate layers in the sequence. Preliminary results of isotope...
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Lower Cretaceous belemnites and their occurrence in Czech Republic
Vaňková, Lucie ; Košťák, Martin (advisor) ; Marek, Jaroslav (referee)
The thesis deals with an complex overview of the Lower Cretaceous belemnites, and their occurrence in the Czech Republic, especially in Štramberk locality. First part provides a brief introduction to the Lower Cretaceous and to belemnite morfology with emphasis on internal skeleton especially of rostrum. Next chapter includes short review of morfometric analysis, which is the most important feature for taxonomy. The following part presents systematics and taxonomy of the Lower Cretaceous belemnite, and their paleoecological use as an indicators for paleotemperatures. There are also mentioned geographical occurrences and migrations of certain belemnite taxa and their stratigraphical evidence in the Lower Cretaceous sediments. The last part deals with the locality Štramberk, which is unique in the Czech Republic because of its stratigraphical evidence of the Lower Cretaceous belemnite fauna. Key words: Belemnites, Lower Cretaceous, systematice, palaeobiogeography, palaeoecology, Štramberk
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Lower Cretaceous belemnites of the locality Štramberk: taxonomy, stratigraphy, palaeoecology, palaeobiogeography
Vaňková, Lucie ; Košťák, Martin (advisor) ; Vašíček, Zdeněk (referee)
The study (MS, diploma thesis) is based on more than 1200 belemnite rostra set from the Lower Cretaceous sediments of locality Štramberk (N Moravia). Investigated rostra come from the collection of Dr. V. Houša, who collected them during the seventies to eighties of the last century, during intensive excavation of the Lower Cretaceous tectonic block named Š-12 "pocket". Belemnite rostra were determined at species and generic levels including 7 species and 18 genera. The majority of belemnite assemblage comes from the Lower Valanginian strata, however, also the Tithonian, Berriasian and Hauterivian taxa are present, what clearly documents the redeposition. The presence of mesohibilitids, known from the Barremian and younger deposits, still remains enigmatic. For better understanding of the redeposition proces, the alveolar infill formed by several generations of sediments, are investigated. Study of these sediments outlines the sedimentary development of the Baška elevation inside the Outer Carpathian system. Preliminary stable isotope data δ18 O and δ13 C received from belemnite rostra show different belemnite life-style during the ontogeny - i.e. juvenile bottom life style and adults inhabiting shallow/warmer waters. Negative values of δ18 O should be correlated with the "Valanginian extinction...
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Lower Cretaceous belemnites (including J/K boundary interval) in the NW Tethys, biostratigraphy, palaeobiogeography and palaeoecology
Vaňková, Lucie ; Košťák, Martin (advisor) ; Michalík, Jozef (referee) ; Fozy, István (referee)
This thesis deals with the belemnite fauna from the Outer Western Carpathians Klippen, its systematic classification, stratigraphical and palaeogeographical evaluation. The palaeontological/palaeobiological approach, together with isotope analyses, including of carbon and oxygen stable isotopes and of strontium isotopes, enabled an integrated investigation of the palaeoecological conditions during the Jurassic/Cretaceous (J/K) boundary interval and the Early Cretaceous age. The Tethyan belemnites are not intensively studied in detail in the J/K interval, as they occur rather rarely in the sections, and/or sedimentary conditions were not suitable for their preservation. Therefore, belemnites are described only from a few sites in the Mediterranean Province. On the basis of recent research, the stratigraphic range of several species previously considered to be from the Tithonian age was extended to the earliest Cretaceous. By contrast, the Lower Cretaceous belemnites (since the late Berriasian) are more abundant. In the classical areas of the Tethyan Realm, it is possible to study the Lower Cretaceous belemnites in great detail and, according to their higher abundance, to determine an individual assemblage corresponding to stratigraphical intervals. Their occurrence is also an important basement for...
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The Jurassic belemnites of northern Bohemia - stratigraphy, palaeobiogeography and possible isotope record
Geist, Jan ; Košťák, Martin (advisor) ; Frank, Jiří (referee)
4 Abstract The work is based on a revision of collection from several scientific institutions from the Czech Republic and the Federal Republic of Saxony (National Museum in Prague, Chlupáč Museum of Earth History, Senckenberg Natural History Collections Dresden, etc.). The collection is based on samples published by Oskar Lenz and George Bruder from the second half of the 19th century. Both authors also processed the findings of other researchers (e.g. Cotta, Weisse). The belemnite rostra were systematically divided into four families, five genera and seven identifiable genera. One rostrum has not exactly been determined. The age of the samples was established to be the Middle and Upper Jurassic (Bajocian- Kimmeridgian). The length of the expected sedimentation in this area has been prolonged to the past (deeper to the Middle Jurassic), mainly due to the finding of the species Megateuthis gigantea Schlotheim, 1820. Earlier research (especially in the 20th century) assumed the extent of preserved carbonate rocks only in the Oxfordian and Kimmeridgian age, with a not much fossiliferous Callovian Brtníky Formation. The studied sedimentary rocks show a significant influence of Milankovich cycles with repeated alternation of carbonate and non- carbonate layers in the sequence. Preliminary results of isotope...
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Lower Cretaceous belemnites of the locality Štramberk: taxonomy, stratigraphy, palaeoecology, palaeobiogeography
Vaňková, Lucie ; Košťák, Martin (advisor) ; Vašíček, Zdeněk (referee)
The study (MS, diploma thesis) is based on more than 1200 belemnite rostra set from the Lower Cretaceous sediments of locality Štramberk (N Moravia). Investigated rostra come from the collection of Dr. V. Houša, who collected them during the seventies to eighties of the last century, during intensive excavation of the Lower Cretaceous tectonic block named Š-12 "pocket". Belemnite rostra were determined at species and generic levels including 7 species and 18 genera. The majority of belemnite assemblage comes from the Lower Valanginian strata, however, also the Tithonian, Berriasian and Hauterivian taxa are present, what clearly documents the redeposition. The presence of mesohibilitids, known from the Barremian and younger deposits, still remains enigmatic. For better understanding of the redeposition proces, the alveolar infill formed by several generations of sediments, are investigated. Study of these sediments outlines the sedimentary development of the Baška elevation inside the Outer Carpathian system. Preliminary stable isotope data δ18 O and δ13 C received from belemnite rostra show different belemnite life-style during the ontogeny - i.e. juvenile bottom life style and adults inhabiting shallow/warmer waters. Negative values of δ18 O should be correlated with the "Valanginian extinction...
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|
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Lower Cretaceous belemnites and their occurrence in Czech Republic
Vaňková, Lucie ; Košťák, Martin (advisor) ; Marek, Jaroslav (referee)
The thesis deals with an complex overview of the Lower Cretaceous belemnites, and their occurrence in the Czech Republic, especially in Štramberk locality. First part provides a brief introduction to the Lower Cretaceous and to belemnite morfology with emphasis on internal skeleton especially of rostrum. Next chapter includes short review of morfometric analysis, which is the most important feature for taxonomy. The following part presents systematics and taxonomy of the Lower Cretaceous belemnite, and their paleoecological use as an indicators for paleotemperatures. There are also mentioned geographical occurrences and migrations of certain belemnite taxa and their stratigraphical evidence in the Lower Cretaceous sediments. The last part deals with the locality Štramberk, which is unique in the Czech Republic because of its stratigraphical evidence of the Lower Cretaceous belemnite fauna. Key words: Belemnites, Lower Cretaceous, systematice, palaeobiogeography, palaeoecology, Štramberk
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