GACR

Next to the classical occurrences in southern Bohemia, western Moravia, northern Austria and Lusatia (Germany), moldavites were found also in the Pliocene sediments in the Cheb Basin. Compared to other localities only a littte is known about the chemicalcomposition of moldavites from this region so far: totally four pieces were analyzed for major elements only using electron microporobe techniques. The aim of the project is to provide as complete as possible chemical characteristics of the moldavites from this region based on more representative sample collection. No trace and minor element determination for the moldavites from the Cheb Basin exists so far - the data proposed to be yielded in the framework of this project will represent the first such determination ever. The detailed chemical composition study will reveal the mutual relationships to Bohemian. Moravian, Lusatian and Austrian moldavites which are not clear at the moment.

Moravian part of the Outer Flysch Carpathians offers an opportunity to study the Cretaceous Oceanic Red Beds (CORB) deposited in different environmental settings. Continuous Bystrá section in the Silesian Unit was chosen as principal section. Detail biostratigraphical research based on foraminifera, dinoflagellata, and nannofossils at the section together with selected methods of sedimentology, petrography, mineralogy, and geochemistry will allow build local stratigraphic standard. The standard willserve as a tool for calibration of marker fossils and correlation with selected CORB sections in the Rača and Bílé Karpaty units as well as inter-regionally. Utilization of the local standard by methods of graphic correlation should provide precise dating of significant events in single sub-basins. As a part of this goal the onset of the CORB in different units will be dated. Correlation of the CORB in single sub-basins and obtained paleoenvironmental data will help to create the paleoceanographic

Multidisciplinary project focused on qualitative/quantitative reconstruction of plant habit and structure of Westphalian peat-forming ecosystems in unusual details based on study of in situ buried fossils excavated from volcanic ash beds in the Late Palaeozoic continental basins of the central and western Bohemia. This spectacular material provides unique data on density of vegetation including the understorey, vertical structure of the plant assemblage, and aut- as well as synecological demands of individual species. It also allows correlation of various plant organs commonly found isolated in clastic sediments without any relationship to their parent plants. Mode of occurrence / preservation and association with other species, in situ spores, morphological and, if preserved, also anatomical details (e.g. chared tissues) will be studied using common and special paleobotanical techniques as well as coal petrology, palynology and plant taphonomy methods. Comparison of dispersed spore spectrum

The Ordovician sedimentary sequences in the St Petersburg Region represent a unique sequence of condensed sedimentation, dominated by bioclastic carbonates of temperate zone. The study of ichnofabric of these sediments can answer the following questions:l, to decipher individual episodes of sedimentation, erosion and diagenetic alterations of the Ordovician rocks in the St. Petersburg Region and in all the Baltica; 2, provided a conspicuous symmetry of ichnotaxa and ichnofabrics occurrences across the individual sedimentary sequences will be demonstrated, both local and global eustatic curves for the Early and Middle Ordovician will be precised; moreover, paradigms on the influence of the sea level to the ichnobabric might be upgraded; 3, previous studies in the area have ascertained intensive deep bioturbation and bioerosion of the strata, which are biostratigraphically equivalent to the Lower Ordovician. Such an intensity of deep bioturbation have not been presumed yet for the Early Ordovician.

Relationships will be studied between stress-strain behaviour, the acoustic emission and microcrack propagation. The experimental study of the relationship between rock microfabric and modes of failure has direct effect on the solution of some problems of underground excavations' stability (mining, radioactive waste repositories construction, stability of underground engineering structures). Statistical autocorrelation analysis of acoustic emission events will facilitate determination of initial stress-state of the rock sample or rock mass, respectively. It is supposed that independent method - frequency analysis of radiated acoustic events - will confirm results of autocorrelation analysis. Analysis of radiated signals (first on-sets of the P-waves) will help interpretation of failure mechanism. The direct methods (mainly computer assisted image analysis, visualisation of brittle fractures in deformed rock samples) for evaluation of microcrack initiation and crack damage stress levels will

To prove the variability and dependence of concentrations of inorganic pollutants (CIP) throughout the individual episodes on the meteorological conditions by means of the monitoring and analyses of samples of falling (gravitational)- and deposited (occult) atmospheric precipitation events. To assess the response of these types of precipitation in the bedrock and soils and in the metabolism of dominant tree species on the basis of complex study carried out in a forested catchment. CIP in the deposited precipitation depends on the microphysical properties of fog, in particular on the water content (LWC) and on the local contamination sources. In falling precipitation, it is possible to expect the dependence of CIP on the transport trajectory,character of the precipitation cloudiness, its vertical extent and on the process of its feeding by pollutants throughout the transport. Dependence between CIP in the deposited and/or falling precipitation and the dynamics of biogeochemical cycles.

Middle Devonian radiolaria were reported from the Barrandian formerly (Bouček, Petránek, Čejchan 1986, Braun & Budil 1999), indicating an ocurrence of a rich and diverse radiolarian fauna of quite unique stratigraphic position among the world's paleoziocradiolarian localities. However, this fauna has not been studied monographically yet. Both albaillellid and entactiniid polycystine radiolarians are present within the fauna. Previous studies indicate a presence of several evolutionary lineages ofceratoikiscids, with several new species characteristic of the Eifelian age. Radiolarian fauna is accompanied by megafauna of goniatites, bivalves, trilobites, etc., and, best of all, also by conodonts. Thus, the hopefully newly established localradiolarian zones would be able to be directly correlated with the standard conodont and goniatite zonations.

The main point of the project is the study of the development of the brachiopod assemblages through the Triassic x Jurassic boundary, and the detailed taxonomic revision of new finds of brachiopods with an accent on inner structures and variability ofthe external morphology of shells. The large comparative material of brachiopods from this stratigraphic span deposited in the collections in Innsbruck and Vienna will be also studied. Based on the detailed study of the characteristic localities andsections in the Northern Calcareous Alps, completed with the study of new brachiopod material, the changes in the representation of particular groups of brachiopods during the critical period of reduced marine asssemblages between the Uppermost Triassicand Lowermost Jurassic will be documented. The results of the palaeontological revision of brachiopods will be completed by new data gained recently by other geologists.

The durability of natural stone is assumed to be intimately related to pre-peak fracture process (crack initiation and damage), which can be derived from stress-strain behaviour during compression and/or tension. Compared to previous empirical evaluation (freeze-thaw cycles, salt crystallization, hydric dilation) of the durability of natural stone, in this new project this will be resolved through experimental rock mechanical tests employing acoustic emission monitoring. Testing will include rock fabric analyses prior and after the tests on porous rocks (sandstones, silicites, tuffites, bioclastic limestones) showing variable porosity (5-30 vol. %), pore size distribution, granulometry, degree of cementation, and physical properties. Prior to the rock mechanical tests, certain specimens will be artificially weathered and/or consolidated in order to evaluate effect of rock fabric modification on the mechanical properties. From the stress-strain curves, energetic parameters of deformational process will be derived as a key factor influencing the durability of natural stone.

Salt weathering is considered to be a key factor for evolution of many sandstone landforms. The grant project is aimed to characterize the properties and processes, which are critical for salt weathering, but they were not studied in detail under eld conditions. These are among others the migration of water, vapour and dissolved salts in surcial zone of sandstone/its crust. Hypotheses concerning fundamental role of evaporation rate temporary changes to cavernous weathering will be tested as well. In Strelec Quarry (active sandstone quarry with abandoned exposures of various ages including the incipient crusts) the methods adopted from laboratory techniques will be applied. Their results will be tested by fully destructive but proven techniques. Developed approach to study and characterize the processes in surface zone of sandstone will be consequently applied to natural sandstone exposures in the Czech Republic