Geology, Geophysics & Environment
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ISSN 2299-8004
e-ISSN: 2353-0790
Issue Date
2024
Volume
Vol. 50
Number
No. 4
Description
Journal Volume
Geology, Geophysics & Environment
Vol. 50 (2024)
Projects
Pages
Articles
An attempt to determine the cause of the strong tremor responsible for a rockburst in a hard coal mine based on numerical modeling and spectral parameters
(Wydawnictwa AGH, 2024) Wojtecki, Łukasz; Krawiec, Krzysztof; Ćwiękała, Mateusz; Dzik, Grażyna
Seismic and rockburst hazards represent significant challenges during the longwall mining of coal seams. One analytical approach to assess the potential for rockburst hazards involves reconstructing the stress conditions within the rock mass. This article reports on the findings from three-dimensional (3D) numerical modeling aimed at examining the distribution of maximum shear stress within the rock mass amid the longwall mining operations of the 703/1 coal seam in a mine situated in the Upper Silesian Coal Basin, Poland which was disrupted by a rockburst incident. On the day of the rockburst, substantial concentrations of maximum shear stress were identified in a thick sandstone layer proximate to the boundary of the overlying 624 coal seam located significantly above the 703/1 coal seam. The calculated maximum shear stress demonstrated an increase of approximately 80% over the values observed in the absence of edge effects. Furthermore, also higher concentration of maximum shear stress was identified within the geologically weaker strata adjacent to the 703/1 coal seam. These observations facilitated the classification of the examined rockburst as a stress-stroke phenomenon. Additionally, the study determined the spectral parameters of the tremor, which possessed an energy of 9.8 × 10$^{7}$ J and triggered the analyzed rockburst. The ratio of the seismic energy of S and P-waves confirmed a shear mechanism in the focus. The scope of inelastic deformation within the focal zone was also quantified. Following the event, the rock mass that had been destressed due to the significant tremor and subsequent rockburst exhibited reduced seismic activity upon the resumption of longwall mining of the 703/1 coal seam.
An investigation of rare earth elements in sewage sludge generated in Poland
(Wydawnictwa AGH, 2024) Kostrz-Sikora, Paulina
According to Statistics Poland, an average of around 1 million tonnes DM of sewage sludge has been generated in Poland annually over the past several years, of which approximately 30% has been used in nature, e.g. in agriculture, to grow plants for compost production, or for land reclamation (Statistics Poland 2004–2022). Most research on sewage sludge has focused on investigating its fertilizing value (nitrogen, phosphorus), identifying the composition of organic matter and determining the total content of heavy metals (including primarily cadmium, copper, nickel, lead, zinc, mercury and chromium) and the forms of their occurrence that determine their mobility and bioavailability. The occurrence of rare earth elements (REEs) in sewage sludge has hardly been addressed in research, even though their presence in production processes and everyday objects is increasingly common. The results presented in this article of studies of the concentrations of individual REEs in sewage sludge from selected industrial and municipal wastewater treatment plants located in Poland indicate that they are significantly lower than the average lanthanide level in the Earth’s crust. This may suggest that anthropogenic sources of REEs do not affect the composition of the wastewater and sludge studied. The calculated median concentration of ?REE in sludge from industrial wastewater treatment plants is 9.47 mg/kg, whereas in municipal sewage sludge, the midpoint value for REE concentration is 13.5 mg/kg. Normalization of the obtained results with respect to Post-Archean Australian Shale (PAAS) and to topsoil and subsoil from Poland shows that the sludge is generally depleted in REE relative to the standards used. An assessment of the contamination of sewage sludge with rare earth elements, based on the calculated values of the geoaccumulation index $(I_{geo})$ for these elements, also shows that the content of lanthanides in the studied sewage sludge is lower than in the soils of Poland.
Structure recognition and fluid flow potential based on well data and geological field investigations. A case study of the Istebna Beds, Silesian Unit, Carpathians
(Wydawnictwa AGH, 2024) Krakowska-Madejska, Paulina I.; Puskarczyk, Edyta; Starzec, Krzysztof; Jarzyna, Jadwiga A.; Stadtmüller, Marek
Wydział Geologii, Geofizyki i Ochrony Środowiska
Wydział Geologii, Geofizyki i Ochrony Środowiska
Facies were recognized based on the results of well logging data, using these measurements and conducting a comprehensive interpretation. This was done by first using shaliness (volume of shale) as the main parameter for a geological profile division into petrophysical lithofacies before secondly calculating Flow Zone Index (FZI), utilizing porosity and permeability estimated from well logging interpretation and defining Rock Types on the basis of FZI frequency distributions. FZIs were also determined according to porosity and permeability from laboratory measurements whenever the results were available. Descriptions of cores and cuttings together with the results of geological field investigations were the basis for lithofacies determination. Maps of average porosity, permeability, and FZI values were constructed for the study area. Three types of facies data and maps of reservoir parameters were used to support the recognition of geological structures and their assessment of potential for fluid movement in the rock formation. The facies analyses were performed on the example of the Istebna Beds of the Silesian Unit in the Carpathians.
Deposit potential and distribution of cobalt and nickel in the sludge of chromite placer mining process at Nui Nua ultramafic massif area, Thanh Hoa province, Vietnam
(Wydawnictwa AGH, 2024) To, Xuan Ban; Nguyen, Khac Giang; Tran, Van Duc; Le Tien, Dung
Chromite placer is widely distributed in Quaternary sediments located around the Nui Nua ultramafic massif in Thanh Hoa province, Vietnam. The long-term mining works targeting chromite placer in this area have left a huge amount of waste sludge, up to tens of millions of tons. The paper aims to introduce a deposit potential and distribution of cobalt- and nickel- bearing minerals within the waste sludges generated from the chromite placer mining operations around the mines situated near the Nui Nua ultramafic massif in Thanh Hoa province, Vietnam. Based on field investigations and sample analyses, two groups of waste sludge have been identified: clay-sized sludges and debris waste sludges. The former group is plastic bentonite clay, distributed in depressions and low terrain, and has low contents of cobalt (0.06%) and nickel (0.67%), which is of impractical significance for the recovery purposes of cobalt and nickel. The latter group is usually distributed in relatively high terrain, forming waste sludge ranging from several thousand to hundreds of thousands of tons in volume. These deposits include rock fragments, mineral fragments derived from the Nui Nua ultramafic massif, along with dark spherical nodules rich in goethite, limonite, and Fe-Mn hydroxides, which contain relatively high contents of cobalt (up to 0.75%) and nickel (up to 2.43%) in the waste sludge and chromite placer mines. The cobalt and nickel are mainly concentrated in Fe-Mn nodules made up of goethite, limonite, todorokite, and other Fe-Mn hydroxides. Data from chromite placer explorations, combined with the study results, provide reliable insights into the distribution of cobalt and nickel resources within the waste sludges and chromite placer deposits in the Co Dinh area (northeast of Nui Nua ultramafic massif) and Mau Lam (southwest of Nui Nua massif), Thanh Hoa province. A preliminary estimation of potential resources of Co and Ni metals have been made for the debris waste sludges at Co Dinh and Mau Lam areas based on the ratios of debris particles in the sludges and their contents of Co and Ni along with published resources and reserves of chromite placer ores.
The valorization of flotation tailings in terms of the concept of the circular economy: characterization, environmental risk assessment, and waste utilization routes
(Wydawnictwa AGH, 2024) Mikoda, Bartosz; Potysz, Anna; Siepak, Marcin; Kmiecik, Ewa
Flotation tailings originating from copper ore processing were evaluated in terms of chemical and mineralogical features, leaching, and resource potential. The results demonstrated that flotation tailings show varying degrees of the leachability of elements when exposed to different pH conditions (2–13); the Zn, Cu and Co leachabilities decrease as pH increases, whereas Mo, Ag and Sb revealed U-shaped leaching trend as a function of pH. Flotation tailings were found to be fairly reactive when exposed to water leaching and rainfall conditions. The environmental risk analysis demonstrated Zn to be the most susceptible element to liberation from the flotation tailings studied. Recovery tests demonstrated sulfuric acid to be slightly more efficient extracting agent as compared to citric acid. Hybrid approach to metal recovery was rather unsuitable for studied tailings due to lower extraction yield (not exceeding 20%) as compared to chemical treatment (not exceeding 40%).