High-resolution stratigraphy of the Lower Badenian deposits in selected cores of the Carpathian Foredeep

Drill cores from IK-1 Iváň and LOM-1 Lomnice u Tišnova (Lower Badenian) was evaluated by several various proxy methods (X-ray fluorescence spektrometry XRF, gammaspectrometry, grain size analysis, RTG diffraction and chemical analysis) in order to obtain data about paleoclimatic and paleogeographic conditions of sedimentation as well as to veryficate applications of these methods on monitored Neogenous sediments. Both wells are situated in the southern part of the Karpathian Foredeep in the Czech Republic. IK-1 is situated in the central area of the basin while LOM-1 lies on the western border of it. According to the biostratigraphic data, both of the observed wells belong to the NN5 zone (Tomanová Petrová & Švábenická 2007). Facial and litologic studies (Nehyba et al. 2007) point to similar sedimentary conditions (shallow-sea sediments of inner and outer shelf) and similar source of clastic material settling in the basin. Results from the X-ray fluorescence spectrometry were used as proxy date for grain size, weathering, oxide-reductive ratios and changes of high of sea-level. For the study, chemical elements were used, especially those which has been confirmed as reliable for given methods, specifically Al, Si, S, K, Ti, Mn, Fe, Rb and Zr. On the other hand, elements showing higher deviations during measuring were excluded, for example Cr, V, T or Ni. According to the results of grain analysis, the sediments can be classified as clay silts and, in only a fraction of cases, silt clays. Medium size of Mz grain (Folk & Ward 1957) was counted and was used to confirm grain proxies. Chosen ratios Si/Al, Ti/Al and Zr/Al (Ver Straeten et al. 2011) were used as grain proxies. Mutual correlations were insignificant, only in case of LOM-1 higher correlation between Mz and Ti/Al was proved. Therefore, the grain proxies cannot be considered reliable. Proxies for weathering show the effects of chemical weathering, which is also proved by high values of the CIA index. For surface-level changes, we used proxy Fe/Al (Clarkson et al. 2014). In IK‑1, the results were compared with ratio of plankton and bentos (Nehyba et al. 2007) and stronger similarity of trends was established. To sum it up, proxy data of studied sediments can be considered partially reliable

Is the cave airflow influenced by external wind?

Based on the case study in Císařská Cave (Moravian Karst), it was tested the impact of external wind on airflow dynamic. Time series of the cave airflow, external wind, and cave/external temperature (signals) were monitored at the lower entrance of the cave during an upward airflow ventilation mode. The periods of the oscillations in both signals (3.8 to 13.3 minutes in the cave airflow and 5.5 to 9.2 minutes in the external wind) were inconsistent. The correlation between both signals was statistically insignificant. The cross correlation did not show any time shift between both signals. These results rather question the generally presumed impact of external wind on cave airflow.Based on the case study in Císařská Cave (Moravian Karst), it was tested the impact of external wind on airflow dynamic. Time series of the cave airflow, external wind, and cave/external temperature (signals) were monitored at the lower entrance of the cave during an upward airflow ventilation mode. The periods of the oscillations in both signals (3.8 to 13.3 minutes in the cave airflow and 5.5 to 9.2 minutes in the external wind) were inconsistent. The correlation between both signals was statistically insignificant. The cross correlation did not show any time shift between both signals. These results rather question the generally presumed impact of external wind on cave airflow

Impact of being evergreen or deciduous on the wood anatomy of the trees in polar regions during the warm geological period : case study from Upper Cretaceous of the James Ross Island (Antarctic Peninsula)

Změny prostředí v důsledku globálního oteplovaní a jejich následky jsou podstatnou a široce studovanou otázkou. Křídové polární ekosystémy nemají v dnešní době obdobu. Proto takové ekosystémy představují unikátní možnost pro studium extrémních prostředí a organizmů se specifickými adaptacemi na ně. Příslušné ekosystémy mohou mít klíčový význam pro pochopení možných budoucích změn na naší planetě. Diplomová práce se věnuje otázce strategie adaptace suchozemských rostlin v období pozdní křídy: stálezeleností a opadavostí. Studovaný materiál pochází z oblasti Brandy Bay a Crame Col na ostrově Jamese Rosse u Antarktického poloostrova a byl sbírán v souvislém sledu profilů od souvrství Kotick Point po souvrství Santa Marta (cenonam až kampán). Ze studovaných 55 vzorků fosilních dřev bylo vybráno a systematicky popsáno pět typických taxonů jehličnanů pro dané geologické období a oblast: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum a Phoroxylon sp. Agathoxylon kellerense (vzorek číslo AN34) byl vybrán pro detailní analýzu a zjištění strategie adaptace jehličnanů na základě anatomické stavby letokruhů. Metodou stanovení strategie adaptace rostliny (procentuální zmenšení buněk; procentuální zastoupení letního dřeva; RMI; náklon CSDM křivky)...Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...Institute of Geology and PaleontologyÚstav geologie a paleontologiePřírodovědecká fakultaFaculty of Scienc

Konodontové platformní elementy z vybraných profilů devonu a jejich aplikace v biostratigrafické korelaci

The presented work consists of three separate papers that have been published in peer- reviewed journals. The published studies summarize and refine the existing knowledge about some conodont faunas of the Devonian with a primary focus on P1 elements and their potential in biostratigraphy. The dissertation thesis consists of three main parts. The first part is designed as an introduction, a summary of the objectives of the presented work, and methodologies used during the conodont sampling and sample processing and samples for thin sections. The second part of the work presents a general overview of the problems of conodont elements in biostratigraphy of the Devonian, characterizes the geological conditions and paleogeographic development of the areas from which the studied elements come from. The third part summarizes the results, brings a discussion on the herein presented data published in articles and contains the final word on the researched issues. The published studies on which this work is based are focused on platform elements of ozarkodinids and icriodontids, whose global distribution in time and space enables their study in different environments and stratigraphic levels. The microfacial characteristics of the studied sections and the issue of conodont biostratigraphy in the Devonian are...Předkládaná práce se skládá ze tří samostatných článků, které byly publikovány v odborných recenzovaných časopisech. Publikované studie shrnují a zpřesňují dosavadní znalosti o vybraných konodontových faunách devonu se zaměřením na P1 elementy a na jejich potenciál v rámci biostratigrafie. Disertační práce se člení na tří hlavní části. První část je koncipována jako úvod, shrnutí cílů předkládané práce a použitých metodik při odběru a práci s konodontovými vzorky a výbrusy na mikrofaciální studium. Druhá část práce slouží jako obecný přehled problematiky konodontových elementů a jejich aplikace v biostratigrafii devonu, charakterizuje a popisuje geologické podmínky a paleogeografický vývoj oblastí, ze kterých studované elementy pocházejí. Třetí část následně shrnuje výsledky, rozvíjí diskusi k publikovaným článkům a obsahuje závěrečné slovo ke zkoumané problematice. Publikované studie, ze kterých tato práce vychází, jsou zaměřeny na platformní elementy ozarkodinidů a icriodontidů, jejichž globální rozšíření v čase i prostoru přináší možnosti jejich studia v odlišných prostředích a stratigrafických úrovních. Kromě toho je zde diskutována také mikrofaciální charakteristika studovaných profilů a problematika konodontové biostratigrafie v devonu. Celkově bylo odebráno a zpracováno 38 nových...Institute of Geology and PaleontologyÚstav geologie a paleontologiePřírodovědecká fakultaFaculty of Scienc