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Earth and environmental sciences cover all planetary and Earth science aspects, including solid Earth processes, development of Earth, environmental issues, ecology, marine and freshwater systems, as well as the human interaction with these systems.
Earth and Environmental Sciences
The Triassic karstic aquifer is the system with the greatest potential for the utilization of thermal waters in Serbia. As an integral part of the Dinaric tectonic unit, the Triassic aquifer extends widely over the western part of the Serbian territory and is characterized by cold waters. In contrast, the same but confined type of aquifer overlain by thick Tertiary sediments in the Pannonian Basin has significant geothermal potential. The major potential for tapping geothermal flow is in the southern and southwestern parts of the Pannonian Basin (Srem) and in the adjacent areas of Mačva and Semberija in the Sava tectonic graben. In these areas the Triassic karstic aquifer has been tapped by several boreholes with depths ranging from 400 m to 2400 m. The temperature of the hottest water exceeds 75 °C, while maximal discharge is 40 l/s.
Although the prospect of wider utilization of geothermal energy undoubtedly exists, some Serbian national plans count on a limited contribution of geothermal energy in renewable energy sources of only 4%. This is probably due to the low level of current utilization, and the inefficient use of even some highly productive wells with a high water temperature, such as those drilled in the most prosperous Mačva region.
Lake Balaton is a large and shallow lake that is of great economic and cultural importance in landlocked Hungary. Even though the lake has been studied extensively in the last century from a large number of scientific aspects, the mineralogy of its sediments has not been fully explored. The mud at the bottom of the lake consists mostly of silt-sized grains of carbonate minerals with compositions between those of calcite (CaCO3) and dolomite CaMg (CO3)2. In order to understand the processes of carbonate precipitation and the influence of water budget fluctuations on the mineralogical character of the sediment, we used X-ray powder diffraction to analyze the changes of cell parameters of carbonate minerals in the upper half meter of the sediment. The major carbonate phase is Mg-calcite that shows a distinct reduction in cell parameters from west to east, reflecting an increase of its Mg-content, in parallel with a gradient of dissolved Mg/Ca ratio in the water. Intriguingly, dolomite, the other widespread carbonate phase in the sediment, also shows a change in cell parameters from west to east, with the deviations from values of stoichiometric dolomite being largest in the Eastern Basin of the lake. The similar pattern of cell parameter changes of Mg-calcite and dolomite suggests that ordered dolomite with slightly anomalous, Ca-rich composition also forms in the lake, probably by direct precipitation from the water. In contrast, protodolomite forms within the sediment through diagenetic processes. Based on our X-ray powder diffraction measurements, we propose a model of carbonate mineral formation and transformation in Lake Balaton. Since the Mg/Ca ratio of the water appears to be the major factor in controlling the compositions of carbonate minerals, and this ratio in turn is governed by the amount of water supply, the properties of the precipitating carbonate minerals are affected by the actual level of the lake water.
This paper deals with the influence of sharp temperature variations on the geochemical fractionation and bioavailability of 241Am, 60Co and 137Cs in Fluvisol soil. The study was performed using soil contaminated with aqueous solutions of 241Am, 60Co and 137Cs in the laboratory and stored for three years at temperatures within the range of 10–18 ºC and soil moisture from 20 to 30 wt %. Afterward the soil was divided into three equal parts and conditioned for one month at 10–18 ºC, −18 ºC and 40 ºC temperature regimes, respectively. The impact of the storage conditions on geochemical forms of the radionuclides was investigated using single extraction of exchangeable 137Cs with 1 M NH4NO3 and sequential extraction of 241Am and 60Co, and by gamma-spectrometric measurement. The influence of temperature rise up to 40 ºC over a period of one month on the transfer factors (TFs) of the radionuclides from the investigated soil to orchard grass (Dactylis glomerata L.) was evaluated. The results showed that deep freezing and a sharp temperature increase continuing for one month led to re-distribution of 241Amand 60Co between the soil phases and provoked an increase of the exchangeable 137Cs. Freezing led to a decrease of 241Am in the residual fraction and an increase of oxide-bound americium. The storage at frozen conditions led to decrease of oxide bounded 60Co and increased immobilization in the residual fraction. Conditioning at high temperature increased the migration ability of 241Amand 137Cs, while immobilization of 60Co was registered. Conditioning at a sharp temperature increase before the growing season led to higher values of the TFs of all the studied radionuclides. This effect was highest for 137Cs. The sharp temperature change of contaminated Fluvisol soil lasting one month was found to create a risk of increased migration and bioaccumulation of radionuclides.
The geologic, geotechnical and rock mechanical background of the area, which includes an underground cavern system, is very complex. Initially, to describe the rock mass properties, the RMR and Q systems were used, while the rock support system was based solely on the Q system. Later, during construction of the repository chambers, the GSI system was also introduced in addition to the above-mentioned rock classification methods. The correlation and usage of these three different rock mass classification systems were investigated.Special methods were used to obtain more accurate tunnel mapping and documentation, which is based on photogrammetry and photo analyzer software.According to the results, the correlation between the RMR and Q values is independent of the rock type; basically, the same equation can be used for all (differences between experimental error). The GSI intervals also closely follows the same trend as the results of the other two methods.
The aim of this paper is to introduce the horizontal sorption technique and to demonstrate its applicability for the observation of porous materials and effect of surface treatments. The horizontal sorption testing method is a new technique, which was developed to facilitate the in-situ assessment of water absorption properties of porous materials. This new technique has some advantages compared to the already existing in-situ testing methods (Karsten pipe method, contact sponge method). It is easy to use, requires no supplementary electric devices, and tight attachment of the measuring tool onto the surface is not necessary. Moreover, the absorption of the water can be easily initiated and then documented. In the present paper several different ways of application of the technique are shown. The testing method was proven to be appropriate for the evaluation of the rate of water absorption, for determination of the sedimentary fabric of the rock (layers and orientation of the fabric results from its formation), as well as the effective depth and nature of three different types of surface treatments. These treatments were (i) organic and inorganic molecules activating bacteria in the stone, (ii) a conventional stone consolidant and (iii) a biomineralizing protective treatment. The new testing method provided valuable information about the nature of all the three treatments. Therefore the horizontal sorption method (HSM) seems to be a highly promising tool for the analysis of porous materials.
In the Hungarian part of the Tisia Block, four occurrences of rhizolith-bearing pedogenic calcrete have been published, three of which are located in southern Transdanubia. Nodular calcrete with beta fabrics was documented from the lower Permian (Cisuralian) continental Korpád Sandstone Formation where the subaerial exposure section was developed on a strongly altered, volcanic shard-rich siliciclastic substrate. Additionally, two locations with Microcodium-bearing calcrete developed on a lower Jurassic carbonate substrate were published in the last few years. The scope of this study is to briefly summarize pedogenic calcrete records known from the Permian to the Cenozoic of southern Transdanubia (Tisia Block, Hungary), and to highlight their regional paleoenvironmental and paleogeographic importance.
This paper presents a status review of the fossil remains discovered in European Russia and assigned to Stephanorhinus kirchbergensis (Jäger, 1839). Similarly to other areas, this taxon appears rare in European Russia, despite its wide distribution. Furthermore, a large part of the S. kirchbergensis material reported in literature is presently untraceable in the Russian museum collections. In fact, from a total of twenty-one sites, the material is physically available from only three of them. In addition, the remains from Podosinik, previously not mentioned in literature, are reported here. The available material has been studied using descriptive morphological characters. This study follows a previous treatment of the related sites and material from Siberian Russia by the same author. Stephanorhinus is considered here as a synonym of Dicerorhinus.
