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This study aims to re-asses hydrodynamic tests of the Submenilite Unit of the Outer Carpathian Flysch Zone sediments, exposed at Přítlucká hora located near Rakvice village in South Moravian region, Czech Republic. We focused on four shallow, 6.0-7.6 m deep hydrogeological wells, drilled by Aqua Enviro s. r. o. company in 2005. The purpose of the drilling was a feasibility study for drainage of western part of Rakvice village. The sediments of the Submenilite Formation of the Ždánice unit that were drilled are dominated by compressed clays, claystones and siltstones, containing thin layers of sand and weathered sandstones. For the purpose of determining hydraulic parameters of underlying aquifer, the company conducted pumping and recovery tests on each of the wells. In this work, we used Jacob's semilogarithmic method to interpret the measured groundwater level data. Hydraulic conductivity and transmissivity parameters were consequently calculated. The resulting transmissivity values range from 1.6 × 10-2 m2/d to 3.7 × 10-1 m2/d and hydraulic conductivity value ranges from 3.6 × 10-3 m/d to 1.0 × 10-1 m/d. The calculated index of transmissivity Y corresponds to 4.32-4.57 and index of conductivity Z ranges between 5.80 and 6.27. The values of index of transmissivity Y from this study are generally comparable with results presented by previous authors and demonstrate very low transmissivity of the rocks of this unit mostly built by non-permeable pelitic rocks. [ABSTRACT FROM AUTHOR]

The paper provides detailed information on the natural radioactivity of sedimentary rocks in the northeastern part of the Moravo-Silesian Palaeozoic Basin in the Bohemian Massif. The studied area is dominated by the Lower Carboniferous flysch sediments belonging to the Horní Benešov, Moravice, and Hradec-Kyjovice formations (from botttom to the top). These three flysch formations consist of siliciclastic sediments, mainly graywackes, siltstones, silty shales, and clay shales, while conglomerates are less abundant. The overlying sediments of the Ostrava Formation (Namurian) occur on the eastern margin of the studied area. The Ostrava Formation has a character of a paralic coal-bearing molasse with alternating beds of sandstone (or arkose), siltstone and claystone. The sediments often have an elevated content of organic matter, concentrating into coal seams. The rocks of the Ponikev Formation (Devonian) occur in a narrow belt in the western part of the studied area. The Ponikev Formation consists mainly of silicites. Potassium, uranium and thorium contents were measured using a laboratory gammaray spectrometer in 1612 rock samples from 672 localities on five map sheets (1: 50 000 scale). The calculated values of mass activity of 226Ra equivalent (am) demonstrate that the natural radioactivity of sedimentary rocks of all three flysch formations is lower or similar to that of the average Earth crust (about 180 Bq.kg-1). The radioactivity of flysch sediments increases with decreasing grain size from psephites (average am is 122 Bq.kg-1) to psammites (144 Bq.kg-1) and to aleurites + pelites (188 Bq.kg-1). Siltstones and claystones with a low organic matter content (226 Bq.kg-1), coaly siltstones and coaly claystones (240 Bq.kg-1), coaly sandstones and arkose sandstones (232 Bq.kg-1), and coal (202 Bq.kg-1) of the Ostrava Formation show slightly higher average am values. The relatively high radioactivity of these sediments is related to the elevated content of uranium (7.9 ppm on average). [ABSTRACT FROM AUTHOR]

Most methods of evaluating river system contamination use an enrichment factor, but there is no consensus concerning the specific values of the natural geochemical background to be. This is critical for evaluation of the anthropogenic loading. Taking into account that the final evaluation is strongly dependent on the choice of this parameter, the aim of the paper is to show the importance of the choice of the natural background in assessing the pollution degree of river sediments. Element concentrations of the surrounding rocks are considered to be the natural geochemical background. The Svratka River springs in the Žďárské vrchy Highlands. It flows through crystalline rocks in upstream, and further then through metamorphic volcanic rocks, sediments of the Boskovice furrow and plutonic rocks of the Brno Massif. Further on, it flows through a straight watercourse over the plain of the Dyje-Svratka deep valley, and the downstream flows through Miocene sediments of the Carpathian foredeep and flysch units of the Western Carpathians (Fig. 1). 24 samples of river sediments were taken from the Svratka River and its tributaries (Fig. 1). The samples were decomposed in a solution of 1 ml HF (40%) and 3 ml HNO3 (65%). The Al, Ti and As contents were determined by AAS, the Pb, Zr contents were determined by FAAS, and Cr and Ni element contents were determined by ICP-MS (Table 2). The Enrichment Factor (EF) was calculated for each sample using Al, Ti and Zr as reference elements and recommended concentration of the natural background values in Table 1. The resulting EF values are very different (Fig. 2a, b). The results of the statistical processing for lead, arsenic, nickel and chromium (Fig. 3a-d) using the reference elements titanium, aluminium and zirconium demonstrated that the choice of the reference element is not the main factor that significantly influences the final evaluation. The choice of the appropriate natural geochemical background value is absolutely crucial for the evaluation of the anthropogenic loading. [ABSTRACT FROM AUTHOR]

Karst cave and landform occurrences within the Czech part of the Outer Western Carpathians and the Vienna Basin are rare. They are restricted primarily, but not exclusively, to three areas: (i) the Štramberk karst and (ii) the karst of the Pavlovské vrchy Hills, both developed in the Upper Jurassic to Lower Cretaceous limestones present as tectonic klippen or olistoliths within the flysch nappes and (iii) the Mušlov karst in the Middle Miocene limestones of the Vienna Basin. Here we report on a karst cave V Mankově skále in another area, at Myslíkovské Lurdy, locality in the southern part of the Palkovické hůrky Hills near Frýdek-Místek town. Although this cave has been known among the locals for many years, its lithology, stratigraphy, karst geomorphology and structural control have never been described in detail. This paper aims to fill in this gap. The V Mankově skále Cave is a 10 m long karst cave with an entrance located at the outcrop of conglomerate layer consisting of massive intraclasts of the Štramberk limestones. The analysed samples of conglomerate contain clasts of detrital biogenic limestone, sandstone a rarely also phyllite. Clay flow rolls found at the bottom of sandstone overburden of the conglomerate bed contain dinoflagellate assemblage indicating a material redeposition during the Upper Campanian/Lower Maastrichtian period. The newly studied landforms represent the karst within the youngest host rocks on the territory of the Outer Western Carpathians in Czechia, making part of the Late Cretaceous Palkovice Fm. within the Baška Development (Silesian Unit). Numerous wall scallops and karren forms have been identified on the cave walls, indicating genesis under phreatic conditions. However, the structural analysis and cave morphology indicate that the cave development is probably also related to mechanical effect of gravitational slope movements. Brittle deformation zones within the rock massif, manifested by steeply dipping NE-SW and NW-SE striking fractures, represent the main structural control of the cave. The results of electrical resistivity tomography suggest that other karst forms can be probably found within another fracture zone up the slope. Tracer tests revealed that the spring of about 1m long stream running through the cave is located about 20 m further to south underneath the deluvial and fluvial sediments of the Bačův creek. It flows out as four adjacent springs with individual discharge of the order of 10-2 l. s-1. It can be deduced that minimum volume of the karst conduit corresponds to 88 dm3. [ABSTRACT FROM AUTHOR]

The Oligocene Menilite Formation represents the most important source rock in the Outer Flysch Carpathians. However, only a few studies describe its source rock potential on the territory of the Czech Republic. This overview study deals with 163 samples from the Oligocene Menilite Formation from the Silesian, Subsilesian and Ždánice units in the Czech Republic (Fig. 1) taken from author's previous research. All samples were measured for the total organic carbon content (TOC). Based on it, and with respect to the sampling interval, a subset of 122 samples was used for Rock-Eval pyrolysis. The data are in this study newly completed by additional 35 archival samples from 8 boreholes showing both the TOC and Rock-Eval parameters. Based on the dataset, the genetic potential (GP) and hydrogen index (HI) were calculated. Additionally to 3 archival samples with known oxygen index (OI), 10 samples were newly measured and the OI calculated. The source rock potential was evaluated for each Menilite Formation member separately excluding the 9 older archival samples that cannot be assigned to a particular member. Those samples are interpreted as "undivided" Menilite Formation. The thermal maturity was evaluated by Rock-Eval temperature Tmax. Majority of the studied samples has Tmax < 430 °C (average 418 °C) indicating a presence of immature organic matter (Table 1). In such case, the TOC and HI are considered original. The Menilite Formation has generally a "good" source rock potential (Fig. 2) according to the Rock-Eval GP (average 12.6 mg HC/g rock, range 0.07 - 122.8 mg HC/g rock), whereas the TOC (average 3.19 wt.%, range 0.20 - 16.5 wt.%) indicates "very good" potential. This is presumably caused by inert organic carbon content within the overall TOC. The Chert Member is the most productive among the members according to both the TOC (average 5.19 wt.%), and GP (average 37.0 mg HC/g rock). Based on the refine insight of Rock-Eval HItrue (Table 2), and according to Dahl et al. (2004), the organic matter in the Menilite Formation is classified as kerogen type II (mixed) and I (sapropelic). The kerogen type classification based on the raw (original, not recalculated) Rock-Eval data only (Fig. 3) is misleading due to inert organic carbon content within the overall TOC (Table 2), and several low TOC samples, which significantly reduce the true HI (HItrue, Table 2). Summarizing the data, the Menilite Formation may represent very promising source rock in case of higher thermal maturity which is a limiting factor here. Thermal maturity conditions favourable for hydrocarbons generation are expected especially beneath the Magura Group of Nappes due to higher burial depths. [ABSTRACT FROM AUTHOR]

The research of pseudokarst caves in the Outer Western Carpathians is considered to be an important approach for recognition of various features of slope failures, e.g. its internal structure, depth, spatial extent, structural control, recent movement, age, etc. However, lithology and stratigraphy of rocks exposed inside the pseudokarst caves are still completely neglected. The results of petrographic, mineralogical and micropaleontological study of beds exposed in walls of the Kněhyně Cave are presented. Situated within southeastern slope of the Kněhyně Mt. in the Moravskoslezské Beskydy Mts., the Kněhyně Cave is a crevice-type cave developed within the middle member of the Godula Formation in the Silesian Unit. The investigation within the Kněhyně Cave enabled us to document the complete vertical profile of the cave. The lithological section of the cave represents a typical proximal flysch sequence characterized by alternation of the coarse-grained sandstones with thickness often reaching ~ 3.5 m and up to ~ 0.06 m thick aleuropelites. The mineralogical and paleontological analyses were carried out on 5 rock samples representing the finest members of turbidite cycle, corresponding to Td/Te interval of the Bouma sequence. High content of mica (50-70 vol. % of illite-muscovite; apparently 2M1 and 1M polytypes) and feldspar minerals (albitic plagioclase, potash feldspars) were proved by X-ray powder diffraction analysis. The amount of quartz is low (8 wt. %). The aleurites/pelites contain a large number of phytoclasts and deep-water dinoflagellates, indicating a material redeposition by turbidity currents. The identified dinoflagellate assemblages may be assigned to Lower/Upper Campanian transition. [ABSTRACT FROM AUTHOR]

The flysch rocks of the Outer Western Carpathians have been typically and repeatedly affected by deep seated gravitational slope deformations with evolution of typical certain landforms such as rocky headscarps and tens of meters deep crevice-type caves. The origin of these forms can be ascribed most frequently to the humid periods of the Holocene. The relief is typical of structurally predisposed rock scarps and rock towers. The rock surfaces are very often disrupted by subvertical joints, which divide the rock massif into individual rock blocks. Some joints can be gravitationally widened with a vertical shift of the rock blocks greater than 1 m. In the years 1988 and 1990, members of the Czech speleological society installed the glass indicators on such joints between the rock blocks in four different crevice-type caves for identifying active gravitational shifts. In total, 120 glass indicators were installed there. The current state of glass indicators was in- vestigated after 26-28 years since their installation. Altogether 68 indicators were found. Twenty four indicators were fully intact, nineteen were destroyed or missing, but no shifts were identified, and the shape of 6 other indicators was impossible to reconstruct. Nine glasses were found broken. Shifts up to 5 cm were identified at 10 indicators. The shifts of particular blocks do not indicate any overall movement of the whole rock massif or a general movement of the slope. Whether the movements were gradual or sudden is not known as yet. [ABSTRACT FROM AUTHOR]