Wojciech Mastej
AGH University of Science and Technology
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Featured researches published by Wojciech Mastej.
Geologos | 2015
Wojciech Mastej; Tomasz Bartuś; Jerzy Rydlewski
Abstract Markov chain analysis was applied to studies of cyclic sedimentation in the Coal Complex of the Bełchatów mining field (part of the Bełchatów lignite deposit). The majority of ambiguous results of statistical testing that were caused by weak, statistically undetectable advantage of either cyclicity over environmental barriers or vice versa, could be explained if only the above-mentioned advantages appeared in the neighbourhood. Therefore, in order to enhance the credibility of statistical tests, a new approach is proposed here in that matrices of observed transition numbers from different boreholes should be added to increase statistical reliability if they originated in a homogeneous area. A second new approach, which consists of revealing statistically undetectable cyclicity of lithofacies alternations, is proposed as well. All data were derived from the mining data base in which differentiation between lithology and sedimentary environments was rather weak. For this reason, the methodological proposals are much more important than details of the sedimentation model in the present paper. Nevertheless, they did reveal some interesting phenomena which may prove important in the reconstruction of peat/lignite environmental conditions. First of all, the presence of cyclicity in the sedimentation model, i.e., cyclic alternation of channel and overbank deposits, represents a fluvial environment. It was also confirmed that the lacustrine subenvironment was cut off from a supply of clastic material by various types of mire barriers. Additionally, our analysis revealed new facts: (i) these barriers also existed between lakes in which either carbonate or clay sedimentation predominated; (ii) there was no barrier between rivers and lakes in which clay sedimentation predominated; (iii) barriers were less efficient in alluvial fan areas but were perfectly tight in regions of phytogenic or carbonate sedimentation; (iv) groundwater, rather than surface flow, was the main source of CaCO3 in lakes in which carbonate sedimentation predominated; (v) a lack of cyclic alternation between abandoned channels and pools with clayey sedimentation; (vi) strong evidence for autocyclic alternation of phytogenic subenvironments and lakes in which carbonate sedimentation predominated was found in almost all areas studied.
Journal of Physics: Conference Series | 2016
Marcin Zych; Robert Hanus; Marek Jaszczur; Anna Strzępowicz; Leszek Petryka; Wojciech Mastej
Full description of a two-phase liquid-gas flow requires the designation of lot parameters. First one, which describes which part of the pipeline is fulfilled by the gas, is the void fraction. Moreover the share of gas in a flowing mixture determines the structure of the flow and also affects the velocity of the individual phases. In that case void fraction can be determined by use the gamma absorption method, as well as other flow parameters may be evaluated by the same equipment. In addition the article presents the calibration of radiometric set, which consists of gamma radiation source Am-241 and scintillation probe NaI(Tl), for determination of the void fraction, illustrated by exemplary results of the described method application to various structures of air-water flow in the horizontal pipeline.
Geoturystyka | 2009
Tadeusz Słomka; Marek Doktor; Tomasz Bartuś; Wojciech Mastej; Marek Łodziński
Geoturystyka | 2009
Tadeusz Słomka; Tomasz Bartuś; Wojciech Mastej; Marek Łodziński; Wojciech Mayer; M. Stefaniuk; Marek Doktor; J. Koźma; S. Cwojdziński; A. Stachowiak
Annales Societatis Geologorum Poloniae | 2010
Marek Doktor; Andrzej J. Krawczyk; Wojciech Mastej
Archive | 2009
Wojciech Mayer; Wojciech Mastej
Archive | 2009
Marek Doktor; Wojciech Mastej
Geotourism/Geoturystyka | 2009
Marek Łodziński; Wojciech Mayer; Michał Stefaniuk; Tomasz Bartuś; Wojciech Mastej
EPJ Web of Conferences | 2015
Marcin Zych; Robert Hanus; Leszek Petryka; Dariusz Świsulski; Marek Doktor; Wojciech Mastej
Geoturystyka | 2009
Tomasz Bartuś; Wojciech Mastej; Marek Łodziński