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Revision of historical ichthyosaur fossils (Ichthyosauria, Reptilia) in the collections of the Chlupáč's Museum of Earth History
Rollingerová, Nicola ; Mazuch, Martin (advisor) ; Chroust, Milan (referee)
The presented thesis deals with ichthyosaur fossils in the collections of the Chlupač Museum of the History of the Earth (hereafter CHMHZ). Specifically, these are five original specimens originating from the areas of Holzmaden, Germany (four specimens in total) and Hallein, Austria (one specimen). The main goal of the work is a detailed description and identification of all five original specimens. At the same time, this work answers the question whether the original determination of the fossils corresponds to the current systematics of this group. The work also pays attention to the geology of the areas from which the fossils come, the paleobiology of these animals and the current form of their phylogeny and systematics. This work finds that the original identification of the fossils in most cases does not correspond to the current systematics and proposes a new classification for three of the five specimens. All specimens from the Holzmaden site (4 in total) belong to the genus Stenopterygius and are represented by two species: S. quadriscissus (3 specimens) and S. uniter (1 specimen). The fossil from Hallein is in extremely poor condition, so its assignment is based on geographic and stratigraphic data. In this case, the specimen remains in the original genus classification: Mixosaurus.
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Jurrasic calcareous nannoplankton from the northern Bohemia
Martincová, Anna ; Holcová, Katarína (advisor) ; Hrbek, Jan (referee)
Bachelor thesis summarizes the current knowledge of the Jurassic calcareous nanoplankton in relation to areas of northern Bohemia as a literary review. Work chracterize calcareous nannofossil in term of life cycle, ecology and points to its considerable importance for biostratigraphy. Work also describes the Jurassic sediments of the Bohemian Massif and the development of communities in the Jurassic calcareous nannofossils. Part of this work is a summary of the Jurassic expansion of calcareous nannofossils in Europe and creation of his survey through a table. The work also suggests the possibility of using calcareous nannofossils for specification biostratigraphy of northern Bohemia.
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Paleomagnetism and magnetomineralogy of rocks from the Bohemian Massif and Tethyan Realm
Schnabl, Petr ; Pruner, Petr (advisor) ; Hrouda, František (referee) ; Petrovský, Eduard (referee)
Mgr. Petr Schnabl - Dissertation Paleomagnetism and magnetomineralogy of rocks from the Bohemian Massif and Tethyan Realm Abstract The thesis deals with paleomagnetic and rock magnetic properties of Silurian/Devonian and Jurassic/Cretaceous limestones, Paleogene/Neogene basaltic rocks and altered Silurian basalts. The main goal is to determine the history of the Earths' magnetic field from the Silurian to the present. Two lithostratigraphic formations are defined in the Jičín volcanic field on the basis of volcanology, paleomagnetism and radiometric dating. The Trosky Formation (24.6?/18.3 - 15.7 Ma) is composed of several Strombolian-type volcanoes, while the Kozákov Formation (5.2 - 4.6 Ma) is represented by effusive products with a crater vent of a single giant volcano. One Pliocene (4.3-3.3 Ma) and two Pleistocene phases (2.6 -2.1 Ma and 1.8 - 1.1 Ma) of volcanic activity Magnetostratigraphy is a very important tool for the definition of the J/K boundary. The boundary between the Crassicolaria and Calpionella zones is present within geopolarity zone M19n. The boundary between the ammonite zones Jacobi and Durangites also lies close to this point. Paleomagnetic directions of Silurian and Devonian rocks in the Bohemian Massif are very difficult to interpret and have been studied as a challenging problem...
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