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Upper Pleistocene environmental dynamics in central Europe: multidisciplinary research of loess/paleosols sequences and lacustrine sediments
Hošek, Jan ; Lisá, Lenka (advisor) ; Nývlt, Daniel (referee) ; Ložek, Vojen (referee)
The principal goal of this thesis was to provide relevant information on the spatiotemporal dynamics of erosion-sedimentation and weathering processes in the last climatic cycle and to interpret the obtained data in the context of European paleoenvironmental development. Representative sequences of loess, paleosols and lacustrine sediments from the area of the Bohemian Massif, the Carpathian Foredeep, the the Vienna Basin and the northern edge of the Panno-nian Basin were investigated using a wide range of instru-mental tools and paleontological methods. A uniform analytical approach applied to these sedimentary facies has provided ample new information about the paleoclimatolog-ical and paleoenvironmental development of East-Central Europe - an important region in the transition zone from oceanic to continental macro-climatic settings. The individu-al studies included in this PhD thesis cover the complete period of the Upper Pleistocene (MIS 5-2; ~130-12.7 ky BP) and are presented as separate chapters in the order of the superposition of strata. Chapters III/1-3 deal with the results of research into six loess/paleosol sequences (LPSs) situated in the Central Bohemian Massif, throughout the Moravian Valleys, and at the northwest and north edge of the Pannonian Basin. A detailed paleoenvironmental...
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Variability of glaciofluvial sediments micromorphology
Krbcová, Klára ; Křížek, Marek (advisor) ; Lisá, Lenka (referee)
Micromorphology of glaciofluvial sediments were only partially shown by Mahaney et al. (2001). This paper deals with the main diagnostic textures of glaciofluvial sediments and changes of their micromorphology caused fluvial transport. The samples were collected. All samples were collected by Peter Mida and Martin Hanáček in Svalbard in August 2012. Two glacial samples and six glaciofluvial samples were taken near the glacier Bertilbreen and one glacial sample and seven glaciofluvial samples were taken near the glacier Hørbyebreen. Samples were examined under electron microscope. The correlation analyses was used to set the main glaciofluvial microtextures. Similarity of the samples was tested by one-way ANOVA. Increasing numbers of V-shaped pits, rounded grains, meandering ridges and microblocks are typical for characteristic microtextures of glaciofluvial grains which had greater rate of fluvial transport. But the grains mainly transported by glacier had a greater percentage occurence of subangular grains, straight steps, straight and curved grooves, adhering particles, pitting and V-shaped etch pits. Keywords: exoscopy, quartz grains micromorphology, glaciofluvial sediments
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Exoscopy features of fluvial sediments
Dolejšová, Michaela ; Křížek, Marek (advisor) ; Lisá, Lenka (referee)
This thesis studies surface microfeatures of fluvial quartz grains. The genesis of specific surface microfeatures is influenced by specific physical-geographic conditions prevailing in the environment. Fluvial environment gives a various sets of microfeatures according to kinetic energy of the stream. For the purposes of exoscopy grains of upper reaches (Klínový potok), middle parts of streams (Volyňka, Labe) and downstream (Vltava, Knovízský potok) were used and compared with results of other researchers.
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Exoscopy of sediments of glacigenous accumulation landforms
Křížová, Lenka ; Křížek, Marek (advisor) ; Lisá, Lenka (referee)
This thesis looks at the comparison between grain micromorphology of moraines, debris flows and similar accumulations. Moraine samples were taken in the Černé jezero Lake area, Bohemian Forest, in the Velická dolina Valley, High Tatras, and in the Labský důl Valley, Krkonoše Mts. Samples of debris flows and unverified accumulations were taken in the Důl Bílého Labe Valley, Krkonoše Mts., and further samples of accumulations were obtained from the valley of Prudký potok Stream, Králický Sněžník Mts., the valley of Vražedný potok Stream and Velká Kotlina, Hrubý Jeseník Mts. Sediments were examined under electron microscope and their morphological characteristics and influence of the environment were identified and described. Calculated exoscopic moraine standard was used for comparison of examined forms of relief using distance coefficients, statistical analysis were carried out which identified diagnostic characters for distinguishing moraines and debris flows. There was also calculated exoscopic standard for different types of moraines (frontal, lateral, basal). This research highlighted the differences between moraines and debris flows, and between different types of moraines. The study also proved that typical glacial microtextures, that are generally accepted, occur at similar levels on grains...
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Magnetic fabric and mineralogy of cave deposits in Botovskaya Cave (Eastern Siberia, Russian Federation)
Kadlec, Jaroslav ; Hercman, H. ; Chadima, Martin ; Lisá, Lenka ; Oberhänsli, H. ; Osintsev, A.
The Botovskaya Cave is a typical example of a two-dimensional maze with a total length of explored passages exceeding 60 km, which represents the longest limestone cave system in the Russian Federation. The clastic cave sediments filling the cave passages differ in both mineral and mineral magnetic properties and were deposited under different hydrological conditions. The older portion of the clastic cave fills was derived from overlying sandstones, whereas the properties of younger cave sediments show closer affinity to the soils and weathering products originating on the sandstone plateau above the cave. The cave sediments underwent repeated periods of deposition and erosion during the Tertiary and Pleistocene.
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Geologický výzkum Antarktidy
Masarykova univerzita, Přírodovědecká fakulta, Brno ; Univerzita Karlova v Praze, Přírodovědecká fakulta, Praha ; Česká geologická služba, Praha ; Lisá, Lenka ; Holub, František ; Elster, Josef ; Štípská, Pavla ; Košler, Jan ; Mlčoch, Bedřich ; Nývlt, Daniel ; Mixa, Petr
Hlavním cílem projektu v tomto roce byl geologický výzkum v širším okolí budoucí stanice pro potřeby projektovaného biologického monitoringu: Podrobné geologické mapování území; Studium zdrojových oblastí tillů a glacifluviálních sedimentů na ostrově James Ross ve vztahu k paleoklimatologickému a paleogeografickému vývoji oblasti; Geomorfologický výzkum kamenných ledovců, periglaciálních a paraglaciálních fenoménů na ostrově James Ross; Vývoj zalednění na ostrově James Ross, studium glaciálních a glacimarinních sedimentů terciérního i kvartérního stáří a zalednění. Byly realizovány tyto práce: geologické mapování v měřítku 1 : 25 000; Podrobná geologická dokumentace; Odběr horninových vzorků.
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Paleogeografická‚ paleoklimatologická a geochronologická rekonstrukce kontinentálního zalednění Česka
Česká geologická služba, Praha ; Růžička, Miloš ; Štěpančíková, Petra ; Franců, Eva ; Gába, Zdeněk ; Koubová, Magda ; Jankovská, Vlasta ; Lisá, Lenka ; Vídeňský, Aleš ; Braucher, Regis ; Hoare, Peter G. ; Hanáček, Martin ; Jarošová, Lenka ; Sikorová, Jana ; Tyráček, Jaroslav ; Janásková, Barbora ; Víšek, Josef ; Nývlt, Daniel
Ve zprávě jsou shrnuty výsledky projektu rozdělené podle jednotlivých dílčích projektů: Korelace ledovcových akumulací pomocí sedimentárně-petrologických metod, Paleogeografická rekonstrukce zalednění vybraných oblastí Česka a Geochronologické zařazení ledovcových akumulací a tvarů reliéfu Česka.
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