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2TDK Railway, profile P18. Datings. Final Report.
Bosák, Pavel ; Zupan Hajna, N. ; Hercman, H. ; Horáček, I. ; Kdýr, Šimon ; Kogovšek, B.
Samples for datings were taken in the railway construction (2TDK) near village of Divača, Classical Karst on October 12, 2021: (1) vertebrate bones in cave 2TDK – 002 at the profile P18, cave entrance appeared during the construction operations on cleaned karst surface in a wall of karst depression. Samples of mammal bones and gastropods were collected in situ on cave bottom, and (2) pieces of speleothems occurring in non in situ position on artificially planated surface near the cave opening were collected. U-series: no numerical date was obtained as geochemistry of sample indicate open system, probably due to recrystallization of sample in soil cover. Paleomagnetism: The transition of N- and R-polarized samples cannot be identified more precisely as U-series radiometric dating yielded no numerical results. The transition easily can represent Brunhes/Matuyama boundary (at 773 ka) as well as any of older such transitions (e. g., base of Jaramillo, base of Olduvai). In any case the speleothem grew in a closed cave space with roof, probably as flowstone (inclusion of red soils above the base) and later as baldachin on eroded allogenic fill of the paleocave. Vertebrate paleontology: bone remains of small and larger vertebrates represent subrecent to Holocene species. Sorex alpinus represents the species quite rare in fossil record, but recetly limited to variegated woodland habitats with high surface humidity. A chamois Rupicapra rupicapra represents a resident species present in Slovenia throughout all stages of a glacial cycle, recently restricted to mountain habitats.
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Paleomagnetic record of basaltic lava flows on Nelson Island, Antarctica
Haislová, Radka ; Kletetschka, Günther (advisor) ; Pruner, Petr (referee)
Paleomagnetism is geophysical method for determination of former magnetic field orientation on the Earth using measurement of remanent magnetisation of rocks. Combined with radiomagnetic datingk paleomagnetism enables study of time evolution of the magnetic field on the Earth and/or reconstruction of former positions of litospheric plates. This thesis is elaborates on paleomagnetic record of basalt lava flow on the Nelson's Island in Antarctica and summarizes geological data. In the research part of this thesis theory of magnetism is introduced and the paleomagnetism method is emphasized. Additionaly, I provide a short review of magnetic minerals, that can occur in basalt. These mineral can potentialy hold some information about the character of magnetic field of the geological past. Radiometric dating methods are included as atool for determination of absolute age of solidification of ingenous rocks (lava). Specifically, the K-Ar and Ar-Ar dating methods are emphasized. The regional section of this thesis conntains geological overview about the Antarctica and the Nelson's Island with its surroundings.Included is a section about the laboratory devices for measuring vector magnetisation of oriented rock samples (for example rotational and cryogenic magnetometer). The thesis is concluded with its...
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Paleomagnetic record of basaltic lava flows on Nelson Island, Antarctica
Haislová, Radka ; Kletetschka, Günther (advisor) ; Pruner, Petr (referee)
Paleomagnetism is geophysical method for determination of former magnetic field orientation on the Earth using measurement of remanent magnetisation of rocks. Combined with radiomagnetic datingk paleomagnetism enables study of time evolution of the magnetic field on the Earth and/or reconstruction of former positions of litospheric plates. This thesis is elaborates on paleomagnetic record of basalt lava flow on the Nelson's Island in Antarctica and summarizes geological data. In the research part of this thesis theory of magnetism is introduced and the paleomagnetism method is emphasized. Additionaly, I provide a short review of magnetic minerals, that can occur in basalt. These mineral can potentialy hold some information about the character of magnetic field of the geological past. Radiometric dating methods are included as atool for determination of absolute age of solidification of ingenous rocks (lava). Specifically, the K-Ar and Ar-Ar dating methods are emphasized. The regional section of this thesis conntains geological overview about the Antarctica and the Nelson's Island with its surroundings.Included is a section about the laboratory devices for measuring vector magnetisation of oriented rock samples (for example rotational and cryogenic magnetometer). The thesis is concluded with its...
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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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Paleomagnetický výzkum sedimentárních výplní vybraných jeskyní v České republice : závěrečná zpráva k výjimce MŽP ČR
Bosák, Pavel ; Hercman, H. ; Kadlec, Jaroslav ; Pruner, Petr ; Schnabl, Petr ; Hlaváč, Jaroslav ; Drahotová, Jana ; Pavková, Jaroslava ; Petráček, Jiří ; Rajlichová, Jana ; Drbal, K. ; Komaško, A. ; Milka, D.
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Sborník abstrakt z 10. Zámecké konference o nových trendech v geomagnetismu, paleomagnetismu, magnetismu hornin a magnetismu životniho prostředí
The jubilee 10th of the series of "Biennial Castle Meetings", organised jointly by Geophysical Institute of the Academy of Sciences of the Czech Republic and Geophysical Institute of the Slovak Academy of Sciences, is to follow the tradition of the previous nine meetings held each other year since 1988, and thus to promote the information exchange on fresh results in palaeomagnetism, environmental magnetism and physical principles of rock magnetism. Contributions dealing with rock magnetism and its applications in paleomagnetism, archeomagnetism, magnetostratigraphy or environmental magnetism.
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