GACR

Existing global stratotype sections of the lower Silurian Aeronian and Homerian stages have been found inadequate with respect to modern high-resolution tools of stratigraphic correlation and even standard biostratigraphy. In response to current ISSS initiatives, Rhuddanian/Aeronian and Sheinwoodian/Homerian boundary sections exposed at Hlásná Třebaň and Kosov in the Prague Synform will be examined in detail as prospective candidates for new global stratotypes. Biostratigraphic description and correlation of the sections based upon graptolites will be supplemented by chitinozoan and limited conodont data. Horizons and biozones formerly selected to mark the base of the respective stages are well recognizable in these sections. Apart from biostratigraphic markers, geochemical and petro-physical proxies will be studied since trends in carbon isotopic composition and potential changes or cycles in organic productivity and rate of black-shale sedimentation can serve as likely proxies of global environmental changes of chronostratigraphic significance.

The project’s aim is to establish sequence-stratigraphic framework for the Devonian events in carbonates of the Barrandian area and Moravo-Silesian Zone, Bohemian Massif; with emphasis to sediments, facies, paleontological content and indicators of paleoclimate settings.

The Re-Os isotopic system represents unique tool for gechronology of ore mineralizations. The Bohemian massif is very
important metallogenic unit within the European Variscan province, because it hosts abundant mineralizations/deposits of
different types (e.g., hydrothermal Au, polymetalic Pb-Zn-(Ag), hydrothermal U and U-Ag-Bi-Co-Ni, volcanosedimentary Pb-
Zn-Cu and Ni-Cu-(PGE) mineralizations). However, the age of these mineralizations remains mostly unknown and therefore, the
aim of this project is to improve our knowledge about geochronology of selected ore mineralizations, timing/chemistry of
multiple ore generations and its effect on Re-Os geochronology and their genetic linkage to possible base/precious metal
sources associated with different geotectonic units of the Bohemian Massif.

Robust sets of mostly unevaluated and unpublished data and material on macroflora and palynomorphs will be re-examined to produce high-resolution biostratigraphic record of the Late Palaeozoic basins in the Bohemian Massif. This in the combination with high-precision radiometric data obtained from syndepositional tuff beds will serve to study floristic dynamics in a detail within an interval from the Serpukhovian to the Sakmarian (~43 My) as a response to the onset of the Late Palaeozoic Ice Age and related climatic oscillations operating on several scales including high-frequency Milankovitch cyclicity to general trend of increasing aridity and potentially also to tectonic processes. In combination with high-precision radiometric ages of volcanoclastics these data will serve for detailed correlations with paralic basins of Eastern Europe where high-resolution biostratigraphy and radiometric dating exist. Radiometric data further improve parallelization of regional and global chronostratigraphic charts and their calibration with radiometric ages.

The Black Triangle received extreme sulfur deposition for several decades. By association, Hg deposition was undoubtedly also highly elevated, but research on the distribution, dynamics and fate of Hg in the Czech Republic has been rather scarce. This study will examine the fate of legacy Hg and whether it is still “leaking out” of impacted ecosystems even after emissions have been greatly reduced. We will assess the loading of Hg from upland forests to downstream water bodies, and assess the extent of methylation in the uplands. The combined spatial and temporal records will yield new insights into the behavior and controlling factors of Hg and its toxic forms, like methylmercury, at the fine timescales at which hydrologic and biogeochemical changes occur. This study will also advance our understanding of why organic carbon concentrations and quality vary over time with hydrologic conditions, findings that will be especially relevant to global change scientists.

The Medieval castle Veselí nad Moravou represents a unite European site with many well preserved wooden buildings, construction elements, and unprecedented volume of organic remains. Using the multidisciplinary approach will be clarified the environmental conditions within this locality and the anthropogenical influence on the alluvial plain formation.

The aim of the project is to obtain new answers to frequently formulated questions on the form and demise of Late Neolithic rondels using a special methodology. Micromorphological analysis combined with radiocarbon dating and the classic analysis of archaeological finds will be used to resolve specific questions concerning the existence of Neolithic rondels, especially to clarify the method and time of filling rondel dithech.

Central European tektites, moldavites, represent high silica, dry impact glasses, genetically related to the Ries crater. They occur in several discrete areas, sub-strewnfields. Substantial intra- and intersample compositional variations have been reported for them. No larger internally consistent data set, covering their various properties, exists recently to constrain their source material and formational process more precisely. About 150 moldavites representing individual sub-strewnfields and isolated finds from the Czech Republic and possibly also from Lusatia and Austria will be used to collect the new chemical data using INAA, EPMA, and LA-ICP-MS. Chemical composition analyzed both in bulk samples and on the micrometer scale will reveal details of element distribution. Evaluation of these new internally consistent chemical data and critically assessed field geological information would constrain the source material as well as possible original distribution of moldavites, which is important for more accurate modeling of distal impact ejecta formation and transport.

The project is focussed on the estimate of the occult precipitation total and the formulation and validation of pollutant concentration (PC) in different precipitation types (PT) on meteorological conditions, on air particles transport, nature and conditions of the precipitation formation. Water and pollutant input will be evaluated for selected rain/fog events at experimental basins taking account local and distant pollution sources. The project involves experimental and analytical parts. Yearly 12 samples of bulk precipitation and throughfall will be collected. The duration of the project is 5 years in order to obtain at least 50samples of each type of precipitation at the given area which makes possible high quality elaboration of results. The existing data sets of soluble pollutants are available for the project. The main goals of the project are: (i) to estimate the amount of occult deposition using water balance of the forest canopy, (ii) to specify the PC differences in different PT, (iii) to estimate pollutant sources and their impact on the natural environments.

Crystallographic preferred orientation of crystalline rocks will be investigated by neutron diffraction texture analysis and co-related to a number of physical, chemical, and morphological measurements. The study will be performed on two series of rock samples - carbonates and meta-gabbros - taken so as to reflect the material evolution with respect to parameters of petrogenetic processes, namely the pressure and temperature conditions, deformation, and geochemical influences. The texture data will be juxtaposed with the results obtained by electron backscatter diffraction and expressed in form of orientation distribution function suitable for development of models dealing with anisotropy of physical properties: magnetic susceptibility, optical birefringence, electrical conductivity, and velocity of seismic wave propagation. The knowledge will serve to model the relations among the crystallographic preferred orientation, microstructural evolution of the geo-materials under study and their