GACR

Cherts and carbonates represent outstanding and widespread members of Ocean Plate Stratigraphy (OPS) from the Archean to present. Their composition reflects different conditions during their deposition, which can be potentially linked to the contrasting and temporally changing processes that occurred on moving oceanic plates. Additionally, they also provide unique insights into the compositional variations in seawater chemistry and temperature as well as redox conditions of their depositional environment. We will pursue a multi-technique study combining tectonic, structural, and stratigraphic observations with elemental and isotopic (Hf–Nd–Mo–Si–C–O) data to reveal the origin and nature of chert and carbonate successions in ancient OPS sections and test whether they can be used as geochemical proxies for the variable processes occurring on oceanic plates. The project will also contribute to our understanding of paleoenvironmental conditions during the late Proterozoic–Cambrian with implications for global events preceding and synchronous with the Great Cambrian Explosion of life.

The seemingly well-defined terms such as weathering or erosion in fact include a number of interrelated processes. In the last few years, the present team has demonstrated crucial roles of stress and hydraulic fields using simple physical experiments and numerical modelling. This approach led to the explanation of the origin of some of the enigmatic forms in sandstone. Its
applicability is, however, much broader. The submitted project is aimed at the study of weathering processes in granular rocks. Data obtained from advanced weathering experiments and field measurements will produce parameters necessary for the expansion of numerical modelling. This will allow a prediction of erosion in granular rocks. Besides, this approach will permit to describe the effect of stress field on different types of decay, and explain phenomena like granular disintegration, flaking, origin of vaults, etc. The effect of hydraulic field will be also characterized. Understanding of the effect of both fields on weathering promises a wide response across geoscientific disciplines.

The proposed project will explore long-range vertically extensive magma transfer processes linking lower crustal source regions with volcanism at the Earth's surface. We will focus on Early Carboniferous late-Variscan post-orogenic magmatic complexes in the Bohemian Massif that are exposed at different crustal levels. Our multidisciplinary research approach will include field and structural mapping, analysis of anisotropy of magnetic susceptibility (AMS), high-precision radiometric dating using the CA-ID-TIMS, and whole-rock major trace element and Sr, Nd and Pb radiogenic isotope geochemistry. Moreover, we will employ analogue modelling combined with the AMS to simulate rather poorly constrained magma transfer process: diapiric upwelling, helical magma flow and ring dikes. Based on field studies and laboratory experimentation, we aim to develop a conceptual mechanical model of magma transfer through the Earth's crust. In addition, we plan to investigate the causes of spatial–temporal–compositional trends of post-orogenic magmas in the Variscan Bohemian Massif.      

The multidisciplinary project will address the issue of petrogenesis, emplacement

processes, and tectonic setting of Late Archean (ca. 2.9–2.6 Ga) granites in the Bienville subprovince,

NE Canada. In particular, the project will concentrate on analysis of fabric and

architecture of selected plutons, numerical modelling of associated crustal strains, determining

high-precision radiometric age using laser ablation ICP-MS and ID-TIMS and geochemical

composition including trace elements and Rb–Sr, Sm–Nd, and Hf isotopes. The obtained data

will be used to interpret thermal and mechanical conditions in the host rock during

emplacement, durations, tempos, and spatial and temporal patterns of plutonism. These

interpretations will then serve as a basis for a general discussion and testing the hypothesis

whether the Late Archean granites record plume-dominated vertical tectonics or whether they

record modern-style motions of lithospheric plates.

The project investigates the metamorphoses of urban constructions in the course of the 13th centruy, particularly the transition from non-masonry to masonry houses. Its main objective is the analysis of the results of archaeological and building-historical research from Brno, as well as from Prague, Wroclaw and Jihlava, in terms of chronology, typology, layout, ethnicity, etc. The project involves the comparative study and characteristics of the earliest burgher constructions in Central and eastern Europe before the 14th century. Emphasis is placed on an interdisciplinary approach regarding the technology of the buildings, guaranteed by the participation of ethnologists. Another target of the project is a major shift in the interpretation of the excavated contexts. A key part is the analysis of an extensive series of samples of fills and floors by means of the geoarchaeological method. The application of this method will elucidate, in particular, the function and length of use of some of the unearthed structures. The main outcome of the project is a collective monograph in English.

Black shale formations represent an outstanding and widespread oceanic sedimentary archive from the Archean to present. Their composition can potentially reflect different plate-tectonic settings at the time of their deposition. Additionally, black shales can also provide unique insights into the compositional variations in seawater chemistry and redox conditions of their depositional environment. Using a novel, multidisciplinary approach combining tectonic and structural analysis with geochronology, major/trace and Os–Nd–Cr–Mo–S isotope geochemistry, the proposed project will elucidate the influence of tectonic setting on the composition of black shale formations and explore their potential as stratigraphic markers in accretionary systems at convergent plate margins. Furthermore, the project will contribute to better understanding of processes causing variable oxygen levels throughout the Earth`s history, with a particular emphasis on the Neoproterozoic–Cambrian boundary associated with the Great Explosion of life on the Earth.

The Přídolí Series remains unique in the Phanerozoic as it is the only series recognized by the IUGS that has not been formally divided into stages. This state is being criticized for a long timeas it causes serious difficulties in global correlation of the upper Silurian. The GSSP of the Přídolí Series is in the Prague Synform, where it consists of carbonate facies rich in conodonts accompanied by moderately common graptolites. Therefore the main focus on possible subdivision of the Přídolí is based on integration of graptolite and refined conodont biozonation. The interpretation and timing of paleoenvironmental changes and bioevents across the Přídolí will be based on studies of six selected sections in the stratotype area and will include: 1. biotic data (changes in plankto-nekto-benthic faunas), 2. geochemical data (trace elements geochemistry and δ18O and δ13C isotope analyses), and 3. chemo–physical data (MS and GRS logs). A generalized correlation chart for the Přídolí Series in the Prague Synform with all available data will be a basis for prospective global subdivision. The aim of the project is integration of data on marine faunas and geochemical data from sections of the Prague Synform into a generalized correlation chart for the Přídolí Series in the stratotype area as a key document for the prospective chronostratigraphic subdivision of the Series.

The project combines geochemical, mycological, and molecular biology approaches and aims to provide better understanding of the factors and mechanisms affecting accumulation of Ag, Cu, Cd and Cd in macrofungi. To assess environmental factors in situ, the fractionation and mobility of metals in soil horizons will be analyzed at model sites. Colonization of soil horizons will be studied in Amanita strobiliformis. Pb isotopic composition of sporocarps will be used to trace the soil depth origin of accumulated metals. Distinct mycelial isolates of A. strobiliformis and Hebeloma mesophaeum will be subjected to phenotypic characterization, and subcellular metal species and expression of metal-related genes in mycelia will be investigated; gene-silencing and heterologous gene expression will be used to prove gene function or redirect the flow of intracellular metals. The accumulation of target metals and their intracellular forms will further be investigated in sporocarps of representative taxa, with special emphasis on Russula, Cystoderma a Phaeocollybia spp.

Weathering of sandstone is a widely studied topic by scientists from a number of geological, geomorphological and stone conservation disciplines. This research project is focused on a detailed study of the effect of gravity induced stress on the weathering of natural and artificial sandstone monuments. The fundamental concept – negative feedback between stress and erosion – has been published by us in 2014 in Nature Geoscience journal. A number of issues from this paper, however remain to be resolved. In this research project, elaborate 3D physical and numerical models of both sandstone landforms and man-made monuments (such as the monuments of the ancient town of Petra, Jordan) will be set up. A physically-based model for sandstone degradation will be developed, implemented in the finite element code and used in analyses of various natural and man-made sandstone forms. The effect of load on the erosion rate will be studied experimentally on various natural cemented sandstones. The effect of stress will also be studied on the evolution of open fracture porosity in sandstone aquifers.

The aim of the project is to assemble composite record of the evolution of continental environment in central Europe in period around the onset of Miocene Climatic Optimum from lacustrine sediments of the Most Basin in the Ohre (Eger) Rift. Drill cores 70-380 m long will be analysed from both central and marginal parts of the basin to limit specific influences of local source areas and tectonics. The work will be based on the use of magneto-, chemo- and cyclostratigraphy. Chemo- and cyclostratigraphy will be based on variation of sediment composition reflecting paleoenvironment in the lake watershed as well as lake hydrology; efficiency of proposed tools has already been successfully tested. The project will produce new record of the onset of the Miocene Climatic Optimum and allow its comparison with existing records, e.g. from the Paratethys area. It will contribute to understanding of the environmental changes with unprecedented temporal resolution of 1-2 thousand years.