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Study of fossil wood by modern analytical methods: case studies
Matysová, Petra ; Sakala, Jakub (advisor) ; Soták, Ján (referee) ; Dietrich, Dagmar (referee)
Silicified woods belonging to the three-dimensional permineralised plants are thoroughly studied by palaeobotanists. Their importance is usually underestimated in other scientific disciplines, their mineralogy/geochemistry is poorly known in close relation to other known scientific data. Stone-like appearance and nature of silicified wood is valued mainly in mineralogical markets. Only a complex analytical view can reveal more about their taphonomic past, palaeoenvironments and mechanisms of their formation and preservation. This PhD thesis aims to uncover the potential of instrumental analyses of permineralised woods and design remarkable procedures of observing the wood samples. I have performed petrographical and geochemical analyses and comparison of samples of the Pennsylvanian (Carboniferous) to the Late Triassic age from several localities in the Czech Republic, Germany, Brazil, Sultanate of Oman, Mongolia, USA - Arizona, France, and Antarctica. The selected samples, in most cases taxonomically determined, were observed in qualitative and quantitative way by instrumental imaging and analytical tools. Bulk (XRD) and detailed point analyses were performed. As the samples are very old, the crystallinity of SiO2 was high (α-quartz was their main constituent according to XRD). A rather rare...
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New analytical techniques for the study of amber inclusions
Škorpíková, Šárka ; Prokop, Jakub (advisor) ; Sakala, Jakub (referee)
Amber is an amorphous organic material, a fossil plant resin, mostly produced by Mesozoic and Cenozoic wetland trees. It was often used in jewelry in the past. However, together with the development of paleobiology it has begun to be used as an object of scientific studies, due to its unique abilities to conserve various inclusions in their three-dimensional matter and unusual preservation of their structures. These facts show its important role in the reconstruction of past ecosystems and organism interactions. Various groups of insects and chelicerates groups are typical inclusions that can be found in fossil resins. But the spectrum of these fossil organisms is much wider - from unicellular to vertebrates. For menaningful research of fossil material, precise analytic observations methods are necessary. Their development made a huge progress in last few years. This thesis summarizes the overview of some of these methods and also of inclusions described in several past years from various amber deposits (review of major deposits is included). Powered by TCPDF (www.tcpdf.org)
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Silicified stems of upper Paleozoic plants from the Intra Sudetic and Krkonoše Piedmont basins
Mencl, Václav ; Sakala, Jakub (advisor) ; Pšenička, Josef (referee) ; Florjan, Slawomir (referee)
The late Paleozoic deposits of the Czech Republic are famous for their rich occurence of silicified stems. Despite the fact they have been often described and are well-known among scientists and collectors, their modern evaluation is lacking. This work summarizes results of recent anatomical and paleoenvironmental studies of silicified stems of the Intra Sudetic and Krkonoše Piedmont basins, where are these fossils found very frequently. Based on field research and review of public and private collections, the presence of silicified remnants was proved in several stratigraphic units. Firstly, this work deals with silicified stems of calamitaleans, which are known from the Ploužnice Horizon of the Krkonoše Piedmont Basin, and some gymnosperms. Based on anatomical studies of the secondary xylem and other related features there were found two species of calamitaleans: Arthropitys cf. bistriata and Calamitea striata. Secondly, the more abundant Agathoxylon - type of wood was divided into two groups, which are assigned to cordaitaleans, and conifers. The palaeoenvironmental conditions were partly reconstructed according to sedimentary structures and also according to cordaitaleans - conifers ratio in each wood-bearing layer. Powered by TCPDF (www.tcpdf.org)
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Carboniferous tropical ecosystems of euramerican province
Frojdová, Jana ; Opluštil, Stanislav (advisor) ; Sakala, Jakub (referee)
This thesis deals with the tropical terrestrial ecosystems of Late Carboniferous (Pennsylvanian) time. It is especially focussed on description of the Carboniferous tropical forest and its components. Introductory parts of the thesis deal with the general characteristics of Carboniferous period, including fauna and flora, distributions of continents and how was the climate of this period. Second part follows the characteristics of particular components of the Carboniferous tropical forest, i.e. of individual plant groups and genera, and their ecological demands. Characterised are plants and their assemblages in tropical lowlands as well as in upland areas, rarely preserved in sedimentary record. In the next part I characterise the dynamics of the forest of Carboniferous tropics and discuss potential mechanisms which controlled the floristic changes including plant extinction. The role of climate changes, which had great influence on vegetation, is discussed as the possible main control. In the separate chapter I describe extinction of arborescent lycopsids. Key words: ecosystem, tropical forest, lowland, climate changes
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Study of xylitic wood of the Most Basin using the electron microscopy: systematics and palaeoenvironment
Boudová, Jana ; Sakala, Jakub (advisor) ; Ovčaří, Pavla (referee)
In the Most Basin, there is a rich variety of plant macrofossils, whose findings are described for the first time already in the 19th century. The presented thesis is focused on conifer wood preserved as xylitic stumps in situ. The samples come from the so-called "stumpy horizont No. 31" situated in the roof of the main lignite seam in the Bílina Mine. A detailed xylotomical study with scanning electron microscopy allows their assignment to the Cupressaceae s.l., to the morphospecies Glyptostroboxylon rudolphii and Taxodioxylon gypsaceum.
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Floristic associations of Miocene mires based on fuzite clasts study
Fischlová, Kateřina ; Sakala, Jakub (advisor) ; Gryc, Vladimír (referee)
The thesis presents systematical study and taphonomical evaluation of fusite wood specimens collected in the middle bench of the main lignite seam in the Bilina mine. In the introduction part, there are a general characteristic of the Most Basin and its geological setting with respect to the main lignite seam. Consequently, the charcoal is described in detail. Generally, the charcoaled wood, which was produced during wildfires in the Tertiary forests, shows well preserved anatomical details. The final part resumes systematics and taphonomy of the charcoal specimens collected by the author.
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Late Carboniferous silicified wood from the western part of the Kladno-Rakovnik Basin
Holeček, Jakub ; Sakala, Jakub (advisor) ; Pšenička, Josef (referee)
Kladno-Rakovník Basin and especially its western part is well known for its abundant silicified wood, so-called as "araukarity". The occurrence of these fossils is described since the 19th century, however, modern systematic classification is lacking. Araukarity, linked mainly to the Týnec and Líně Formations, are found almost exclusively on the fields, therefore it was difficult to implement any detailed sedimentological conclusions. The Master Thesis is focused on the western part of the Kladno-Rakovník Basin, where large amount of material was discovered. After a detailed xylotomical study of thin sections and polished cross sections, two different types of wood were discerned. First related to the coniferous and cordaite wood, attributable to the of the morphogenus Araucarioxylon and the second one, rather rare and unknown in the western part of the Kladno-Rakovník Basin represents a calamite wood and it is assigned to the morphogenus Arthropitys. I was able to partially confirm Skoček's (1970) theory, that so-called black araukarity are linked to the grey (Kladno and Slaný) formations.
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Mineral springs of the Karlovy Vary region
Nikolovová, Soňa ; Sakala, Jakub (referee) ; Teodoridis, Vasilis (advisor)
The submitted Thesis is a summary of all the available information on Carlsbad mineral springs. The thesis is divided into three main parts. The first part, considers the general geological proportions of western Bohemia, thoroughly examines the regional geology and describes the formation of the landscape from a statigraphic perspective since the Proterozoic Era. Furthermore it considers the origin and composition of the mineral springs, which form the subsoil in Carlsbad, i.e. Thermal springs plate. The second part solely describes the individual springs as they are. It resolves around their composition, history, locality, temperature and discharge. The last part is dedicated to the historical and present treatment methods, which are practiced in Carlsbad, through the healing effects of the springs on the human organism and their ability to influence individual organs. The goal of this Thesis was to compile the available information and point to the fact that the mineral springs of Carlsbad can be beneficial for a human in many ways.
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