Geology, Geophysics & Environment
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ISSN 2299-8004
e-ISSN: 2353-0790
Issue Date
2017
Volume
Vol. 43
Number
No 1
Description
Journal Volume
Geology, Geophysics & Environment
Vol. 43 (2017)
Projects
Pages
Articles
Malacofauna of the Holocene tufa in the valley of the Ociemny Stream (Pieniny Mts., southern Poland)
(Wydawnictwa AGH, 2017) Alexandrowicz, Witold Paweł
A rich molluscan fauna was found in the outcrop of slope sediments and calcareous tufas in the valley of the Ociemny Stream in the Pieniny Mts. The malacological sequence identified there represents the entire Holocene, but it contains several stratigraphical gaps. From this viewpoint, it is a unique finding within the area studied. In nine samples, 11,000 specimens of 71 species of molluscs were identified. The ecological and zoogeographical diversity of the composition and structure enabled the separation of three faunistic assemblages. The oldest assemblage (with <i>Discus ruderatus</i>) corresponds with the cold period of the Early Holocene and represents shadowed habitats overgrown with the coniferous forests of the taiga type. Its characteristic feature is the presence of glacial relics (e.g. <i>Vertigo genesii</i> and <i>Vertigo geyeri</i>). The other younger fauna (with <i>Discus perspectivus</i>) is typical of the humid and warm climate of the Atlantic Phase. It is characteristic of the habitats of mixed and deciduous forests. Numerous Balkan and Mediterranean thermophilous forms appear in this assemblage. The youngest malacoenosis (with <i>Bithynella austriaca</i>) is typical for the historical times. The particular intervals containing molluscan fauna are separated by gaps corresponding to the erosion phases. Because of the land relief in the valley of the Ociemny Stream, which is not conducive to the development of human economy, no marked anthropogenic deforestation occurs.
Numerical model schematization of a complex hydrostructural Cretaceous groundwater basin for the purpose of protection zone evaluation
(Wydawnictwa AGH, 2017) Gurwin, Jacek
One of the major projects in regional hydrogeological investigations in Poland is a multi-annual cycle of studies on the implementation of programs and documentation in relation to the establishment of protection areas for the Major Groundwater Basins (MGBs). Depending on the size of the area and complexity of the selected aquifer system, the work on the numerical model becomes adequately demanding. The model must in this case be designed as a three-dimensional, multi-layered, taking into account the role of a near the surface aquifer in the potential rate of migration of contaminants. It is particularly difficult to design models of the basins located in the older Mesozoic hydrogeological structures of dual-porosity characteristic, covered by Neogenic and Quaternary sediments. One of these basins is MGB No. 317 (ed. Kleczkowski 1990) identified within the northern Sudetic trough. The boundaries of the MGB are associated with the occurrence of structural aquifer limits, including the relatively large area of outcrops of the upper Cretaceous sediments with a narrow zone of Triassic outcrops. The paper presents the main assumptions of the model schematization, especially regarding the parameterization of hydrostructural conditions in integration with geoinformatic tools and MODFLOW modules. This study is focused on the problems associated with the proper schematization of the multilayer groundwater system on a regional scale, particularly with regard to the first aquifer and its hydraulic contact with the Mesozoic water-bearing horizons of the MGB. Model simulations, together with a semi-analytical analysis of the rate of flow in the vadose zone, finally allowed to determine the protection area of the MGB that is presented.
A new empirical correlation for estimating bubble point pressure using the genetic algorithm
(Wydawnictwa AGH, 2017) Heidarian, Mohamad; Karimnezhad, Masoud; Schaffie, Mahin; Ranjbar, Mohammad
In this paper, a new and more accurate correlation to predict bubble point pressure (P$_{b}$) for Middle East crudes by using the genetic algorithm (GA) is attempted. For this purpose, a total of 286 data sets of different crude oils from Middle East reservoirs were used as training data for constructing the correlation. The general form of the correlation was found by several regressive examinations. To improve the correlation, the genetic algorithm was applied. To validate the correlation, 143 data sets of different crudes from Middle East reservoirs which were different from the training data were used as test data for calculating mean absolute relative error (MARE) and correlation coefficient (R$^{2}$) between the predicted values from the proposed correlation and the experimental values. In addition, the MARE and R$^{2}$ were calculated for previous correlation in the test data. The results show that the proposed correlation is more accurate than all of the previous correlations exclusively for Middle East crudes.
The impact of the mineral composition of Carboniferous claystones on the water-induced changes of their geomechanical properties
(Wydawnictwa AGH, 2017) Małkowski, Piotr; Ostrowski, Łukasz; Bożęcki, Piotr
In this article, the authors describe the characteristics and changes of geomechanical properties of Carbonifeorus claystones as related to their mineral composition and the time of soaking in water. Geomechanical properties, including bulk density, Young modulus, Poisson ratio, unconfined compressive strength, durability index, and swelling index were examined in dry rock samples, and in water-soaked samples after 3 hours of soaking, and 6 hours of soaking respectively. Changes in the geomechanical properties of rocks were also examined as a function of their mineralogical composition. In particular, the properties of rocks were examined in relation to present aluminosilicates and layered aluminosilicates, respectively. Changes in the geomechanical properties were also examined relative to the presence of minerals anatase and siderite. Correlation coefficients between physical parameters and mineral composition were examined. It was determined that the total quantity of aluminosilcates is a better predictor of geomechanical properties after soaking, than only the content of layered aluminosilicates. Calculated correlation coefficients were generally higher for most samples after 6 hours of soaking than after 3 hours of soaking. It was also determined that the increase of bulk density correlates much better with the mineral anatase content, than with the siderite content.
New data on celestine-rich salts in the Wieliczka salt deposits
(Wydawnictwa AGH, 2017) Nowińska, Justyna
Pale brownish celestine-rich salt rocks were found near the Franciuszek Müller gallery, in the chambers of the 3rd level in the Wieliczka Salt Mine. The complex of rock salts subjected to exploration occurred within a large seam approximately 15 m thick. Detailed research revealed that the salt has the form of a block incorporated within the gray salts body and being similar to other blocks of green salts, well known in the upper part of the deposit. A characteristic petrographical feature of the pale brown rock salt owed to the presence of celestine ($SrSO_{4}$). That strontium mineral was re-examined, using X-ray powder data, and scanning microscope observations, with EDS analysis. The investigated rock salts exhibited a mineral association of halite (main component), anhydrite, celestine, calcite, gypsum, clay materials, iron compounds and a small amount of bitumen. Interrigenous sediments and the insoluble part of salt occurred higher content of strontium that in halite. Celestine crystals were observed in two forms: elongated platy crystals, forming fan-shaped aggregates and granular aggregates, strongly associated with anhydrite. On carbonate and sulphate strontium usually appearing as needle shaped aggregates of celestine. No barium minerals were observed. The development and paragenesis of celestine suggested a post-sedimentary origin of these rocks that ought to be connected with diagenetic processes. An important observation that confirmed that thesis was the transformation of fine crystalline anhydrite into platy crystals, recrystallization and primary accumulation of strontium, as a result of evaporation processes.