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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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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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