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Bismuth sulfosalts from the Nistru metallogenetic field, Baia Mare zone, NW Romania
(Multidisciplinary Digital Publishing Institute : Basel, 2024) Damian, Floarea; Damian, Gheorghe; Cook, Nigel J.; Prokofiev, Vsevolod Yu.; Andráš, Peter
An association of bismuth sulfosalts coexisting with native gold is described from a sulfide-rich copper vein in the Nistru area, Baia Mare metallogenetic district, NW Romania. This mineralization is hosted within a Neogene calc-alkaline subvolcanic porphyry quartz-micromonzodiorite stock on the southern border of the Gutâi Mountains. Cu+Au+Bi mineralization represents the inner part of a zoned vein of a type specific to the SE part of the Nistru orefield. The Pb-Zn and Au-Ag veins are located towards the external zone at the boundary of the stock with the surrounding rocks. Bismuth sulfosalts are mainly represented by bismuthinite derivatives and members of the lillianite homologous series. Cosalite, matildite and wittichenite are also present in subordinate amounts. Bi-rich members of the bismuthinite-aikinite series (from krupkaite to bismuthinite) are predominant. A phase with the empirical formula CuPbBi7S12 was also identified and could potentially be a new bismuthinite derivative. The lillianite homologous series is represented by phases with composition between Gus73 and Gus59, with a dominance of members closer to gustavite (Gus97–79) and less abundant members closer to lillianite (Gus49). Native gold and Bi-sulfosalts are closely associated with the main sulfides (pyrrhotite, pyrite, chalcopyrite) and quartz, indicating simultaneous crystallization. Fluid inclusion data for quartz indicate a temperature interval between 205 and 247 °C. The assemblage within this vein was deposited from a low-salinity fluid (0.4–2.6 wt.% NaCl equiv.) and density from 0.80 to 0.87 g/cm3.
Comparison of Cu(II) adsorption using fly ash and natural sorbents during temperature change and thermal-alkaline treatment
(Multidisciplinary Digital Publishing Institute : Basel, 2025) Ďuricová, Anna; Prepilková, Veronika; Sečkár, Michal; Schwarz, Marián; Samešová, Dagmar; Murajda, Tomáš Andrej; Andráš, Peter; Eštoková, Adriana; Čambál Hološová, Miriama; Poništ, Juraj; Zacharová, Andrea; Schmidtová, Jarmila; Veverková, Darina; Biroň, Adrián
Mine effluents represent a serious environmental problem on a global scale. Therefore, the effective treatment of this water is a serious issue in the scientific field. The adsorption process seems to be one of the attractive methods, especially due to the simplicity of design, affordability or high efficiency. The latest scientific knowledge has shown that the use of waste and natural adsorbents is economical and effective. This study aimed to evaluate the efficiency of the adsorption process of natural and waste materials—zeolite, bentonite and fly ash—under the influence of temperature and modification of these adsorbents. The novelty of this study resides in an adjustment of the modification method of adsorbents compared to previous research: thermal–alkaline treatment versus hydrothermal one. Another novelty is the use of modified fly ash from biomass combustion as an adsorbent in comparison with the previously used fly ash from coal combustion. The modification of the adsorbents made the adsorption process more effective at all experimental concentrations. The characterisation of adsorbent samples was performed using X-ray diffraction (XRD). The parameters of the adsorption isotherms, Langmuir, Freundlich and Temkin, were estimated by nonlinear regression analysis. The adsorption capacity of Cu(II) of fly ash was comparable to natural adsorbents. Adsorption processes were better described by pseudo-second-order kinetics. At the end of this study, the suitability of using the adsorbents to reduce the concentration of Cu(II) in neutral mine effluents was observed in the following order at 30 °C: unmodified fly ash > modified bentonite > unmodified zeolite. At the temperatures of 20 °C and 10 °C, the same trend of the suitability of adsorbents use was confirmed: modified bentonite > modified zeolite > modified fly ash. The practical applicability of this study lies in the expansion of knowledge in the field of adsorption processes and in the improvement of waste management efficiency of heating plants not only in Slovakia, but also globally.
Delineating pixels of natural hydrocarbon micro-seepage induced alterations and anomalies in overlying soils and sediments in ugwueme, with ASTER data and band ratio technique
(Hard : Olsztyn, 2024) Enoh, Mfoniso Asuquo; Augustine, Ojanikele Willie; Chiemelu, Ndukwe Emmanuel; Ekwok, Stephen Eguba; Akpan, Anthony E.; Eldosouky, Ahmed Mohammed; Alarifi, Saad S.; Andráš, Peter
The earth’s underlying hydrocarbon-bearing reservoirs frequently leak. These reservoirs leak because of their inadequate sealing, and at high pressure, oil and gas escape vertically or nearly vertically to the earth’s surface as seepage. Micro-seepages on the earth’s surface cause oxidationreduction reactions, which cause anomalies in the soils and sediments beneath them. Remote sensing (RS) and geographic information systems (GIS) are important tools for investigating hydrocarbon micro-seepage-induced changes and anomalies in overlying soil and sediments. In this study, ASTER remote sensing data was adopted to delineate pixels of hydrocarbon micro-seepage-induced anomalies in Ugwueme, south-eastern Nigeria. Band Ratio (BR) was used as a spectral enhancement technique to detect alterations and anomalies in the overlying soil and sediments. ASTER BR of 2/1 improves ferric iron; (5+7)/6 improves clay minerals; (1+4)/(2+3) improves ferrous iron; and 4/(6+9) improves gypsum. The study highlights that BR is an excellent spectral enhancement technique for delineating areas of alterations and anomalies induced by hydrocarbon micro-seepage.
Determination of the bioavailability of barley grains for selected elements
(Nature Publishing Group : London, 2025) Kočík, Karol; Samešová, Dagmar; Schmidtová, Jarmila; Poništ, Juraj; Schwarz, Marián; Andráš, Peter; Veverková, Darina
Potentially toxic elements selected elements pose a risk of contamination and intoxication of agricultural soil. Such contamination is closely linked to threats to human health, as the bioavailability of these elements allows their transfer from crops into the food chain. The aim of the study is to assess the bioavailability of selected elements in barley grain in case of possible soil contamination with selected selected elements. The main novelty of the work consists in the evaluation of the mutual correlation of selected elementss in the bioavailability of spring barley with respect to different treatments. To determine the selected elements bioavailability, the content of selected selected elements was monitored in soil with the addition of NPK and in soil treated with the addition of Mo, Sr, As, Cd. To evaluate the accessibility of selected elements, or their synergism, we used selected methods of inductive statistics. The α-level of 0.05 was set as the decision rule in all statistical tests. Based on our analysis at the unit change of Mo, Mn in spring barley grain increases by an average of 2.14 mg.kg− 1 when grown in strontium-enriched soil. According to our study, barley grain at a unit change of As increases by an average in Mn content by 24.44 mg.kg− 1 with the addition of Cd. According to our results, the addition of Mo to the soil caused an average decrease in Zn at the unit change of As by 3.4 mg.kg− 1. Likewise, an average increase in Mo of 38.45 mg.kg− 1 at the unit change of As (addition of Mo) was confirmed. A negative correlation was confirmed between pairs of elements Mo and Zn without the addition of selected elements. The study confirmed statistically significant differences in the content of selected elements in individual treatments compared to the control NPK sample. At the same time, a positive or negative correlation in the bioavailability of selected selected elements was confirmed.
Mapping landslide susceptibility and risk assessment on fragile ecosystem of Himalayan River basins
(Taylor & Francis : Philadelphia, 2025) Khan, Zainab; Nawazuzzoha, Md; Abdelrahman, Kamal; Ali Sk, Ajim; Fnais Mohammed, S.; Shamim Syed, Kausar; Ahmad, Ateeque; Andráš, Peter
Landslides pose a significant threat in the Himalayan region due to complex geology, steep terrain, and diverse climatic conditions. This study addresses the need for a multi-dimensional approach by integrating Machine Learning with GIS to map landslide susceptibility across Himalayan River basins. Conditioning variables including topographical, climatological, hydrological, and phenological factors, and surface conditions were analysed using SVM to predict landslide susceptibility. For validation, SHAP, ROC curves, and AUC were used. The model attained 87% accuracy. Risk assessment was performed by intersecting land use/land cover (LULC) data with susceptibility zones to quantify agricultural and Urban and Built-up land exposed to landslides, alongside zonal statistics to estimate population risks. The results indicate that 371.5 thousand hectares are at very high risk of landslides, and 209.2 thousand hectares are at high risk, with the Jhelum River Basin emerging as the most vulnerable in terms of population, agricultural land, and built-up areas. This study demonstrates the dominance of hydrological and vegetation-related variables, such as runoff and forest fires, in driving landslide susceptibility, as revealed by SHAP analysis. Integrating susceptibility models with risk assessment, the study provides insights for regional planning, disaster management, and policy-making, stressing targeted mitigation for vulnerable basins.
Mapping of geological structures and sediment thickness from analysis of aeromagnetic data over the Obudu Basement Complex of Nigeria
(Oxford University Press, 2024) Ekwok, Stephen Eguba; Eldosouky, Ahmed Mohammed; Thompson, Edward A.; Ojong, Romeo Akombi; George, Anthony M.; Alarifi, Saad S.; Kharbish, Sherif; Andráš, Peter; Akpan, Anthony E.
In this study, geologic structures, as well as attendant orientations and sediment thickness, in the Nigerian Obudu Complex were delineated using the Centre for Exploration Targeting (CET), and depth determination methods such as source parameter imaging (SPI) and standard Euler deconvolution (SED). The CET, SPI, and SED procedures were applied on the total magnetic intensity data. Also, the enhanced TMI data using analytic signal, first-vertical derivative, total-horizontal derivative, and tilt-angle derivative filters were further subjected to CET operation, with the aim of mapping both subtle and prominent lineaments. In general, mapped geologic structures trends in the NE–SW, NNE–SSW, E–W, and N–S directions. Overall, the dominant geologic structural orientations of NE–SW and NNE–SSW reflect the regional strike orientation. The regional striking of the lineation, which is caused by the Pan-African orogeny and subsequent post-orogenic processes, has an impact on these orientations. The N–S and E–W structural deviations from the main NE–SW and NNE–SSW trends are initiated by the YGS of the post-orogenic events. Overall, these complex geologic structures are probable sites for metallogenic minerals.
Pedochemical fractionation of potentially toxic elements within the context of soil-plant interactions at abandoned heap-field of Caporciano (Italy)
(Springer Nature Switzerland AG : Cham, 2025) Andráš, Peter; Midula, Pavol; Kmeťová, Jarmila; Ševčíková, Janka; Tomaškin, Ján; Drímal, Marek; Janštová, Jana; Masný, Matej; Kharbish, Sherif
Technosols from the heap of the abandoned Italian Cu deposit Caporciano contain important amounts of potentially toxic elements (Crtot., Co, Ni, Cu, Zn, As, Cd and Pb). Copper contents exceed the Italian law limits for industrial/commercial sites. The studied metals in Pinus sylvestris and Quercus petraea (Matt.) Liebl. show strategy of excluders (bioconcentration factor < 1.0) except Ni and Pb (calculated for branches and leaves in Pinus sylvestris) while the translocation factor indicates preferential metal accumulation to leaves/needles (translocation factor > 1.0) in both plant speciments.At the heap the contents of the chlorophyll in leaves in the photosynthetic tissues of Quercus petraea (Matt.) Liebl. (8.56 CCI—chlorophyll content index) are significantly lower as those measured at reference area (17.71 CCI). The goal of the study is to use a modified methodology for the fractional analysis of soils for the determination of the potential bioavailability of potentially toxic elements in six steps. The innovative steps of sequential analysis are adapted with respect to the release of PTEs from the clay mineral surfaces. (fraction I: 1 M ammonium acetate at pH 7; fraction II: ammonium acetate at pH 5; fraction III: H2O2 in ammonium acetate buffer solution; fraction IV: acidic 0.2 M ammonium oxalate (pH 3.2); fraction V: 0.2 M ammonium oxalate and 0.1 M ascorbic acid mixture; fraction VI: 0.5 M ammonium acetate; pH 6). The best bioavailable metals are Cd, Cu, Zn and Pb. The obtained results enable international comparison with similar Cu-deposits.
Petroarchaeological study of medieval ruins of Bzovík fortified monastery
(North University of Baia Mare, 2024) Andráš, Peter; Spišiak, Ján
The article represents the results of the complex petroarcheological study focused on the building material with respect to the restoration of the old fortified monastery Bzovík (Central Slovakia). The aim of the study was to determine the original building material and to suggest the best solutions of the building recovery. The petroarcheological study enabled to describe the present state of the used rocks, their resistance and several types of mortars. The aim of the study was determining the material of building We found that the majority of the building stones are from the Neogene volcanics of the Štiavnica stratovolcano. Mainly effusive and extrusive activity of andesite volcanism. Distinguish the original and more new additional building elements, suggest suitable procedures and materials with respect to the sanitation of the building complex.
Remote sensing and aeromagnetic mapping for unveiling mineralization potential: Nuqrah Area, Saudi Arabia
(Springer Nature Switzerland AG : Cham, 2024) Alarifi, Saad S.; El-Qassas, Reda Abdu Yousef; Omar, Ali Elsayed Ali; Al‑Saleh, Ahmad Mohammad; Andráš, Peter; Eldosouky, Ahmed Mohammed
Lately, Saudi Arabia has been developing its mineral exploration. However, comprehensive studies of the collected data are not accessible. Thus, the purpose of this research is to identify and map the hydrothermal alteration zones and structural lineaments that regulate the mineral occurrences in the Nuqrah region of the Kingdom of Saudi Arabia using remote sensing and aeromagnetic data. To achieve the desired goal of the study, ASTER remote sensing data were employed, and they were processed in several ways, including principal component analysis, band ratio, and false color composites to reveal the zones of alteration and structure lineaments. In addition, aeromagnetic data was employed to map the lineaments controlling the mineralization. These datasets were integrated using GIS tools to generate a new mineralization potential map of the Nuqrah area, which was classified into three classes: low, moderate, and high probability mineralization. The results showed thirteen intriguing anomalies (high potential mineralization) dispersed over the research area to be prospected. Additionally, techniques such as residual, regional, first vertical derivative, and tilt derivative were utilized to detect the potential mineral-related geologic structures. The results were validated by plotting known mineralization sites on our maps. Six significant faulting trends have been found, according to the lineament map and rose diagrams from remote sensing: NE–SW, WNW–ESE, N–S, ENE–WSW, NNE–SSW, NW–SE, and E–W. The research region is most affected by the NW–SE, ENE–WSW, E–W, and N–S trends, which are organized in decreasing order of magnitude, according to the rose diagram of the aeromagnetic maps. The applied approach can be employed to map potential mineral deposits in Saudi Arabia and similar zones around the globe.
Solar PV systems under weather extremes: case studies, classification, vulnerability assessment, and adaptation pathways
(Elsevier : Amsterdam, 2025) Okonkwo, Paul C.; Nwokolo, Samuel Chukwujindu; Udo, Sunday; Obiwulu, Anthony Umunnakwe; Onnoghen, Usang Nkanu; Alarifi, Saad S.; Eldosouky, Ahmed M.; Ekwok, Stephen Eguba; Andráš, Peter; Akpan, Anthony E.
This study examines the significant challenges presented by the rising frequency and severity of climate changeinduced extreme weather events-such as hurricanes, floods, heatwaves, and snowstorms-on the reliability and efficacy of solar photovoltaic (PV) systems. Utilizing case studies from various global places, it underscores the susceptibilities of photovoltaic systems to environmental harm, encompassing structural failure, efficiency decline, and operational interruptions. The study presents a novel, resilience-oriented paradigm that incorporates sophisticated design principles, operational techniques, and policy innovations to alleviate these risks. Principal findings underscore the significance of site-specific risk evaluations, modular and adaptable system architectures, and cohesive resilience planning in photovoltaic system engineering. Proactive operational techniques, such as regular maintenance, emergency reaction plans, and intelligent system monitoring, are deemed essential for sustaining performance in extreme weather conditions. Innovative technological solutions, including resilient materials, sophisticated coatings, durable mounting methods, and thermal management technologies, are emphasized for their capacity to endure intense environmental stressors. The study delineates future research goals, encompassing the creation of innovative materials with superior durability, scalable energy storage integration, structural advances, and greater grid interconnectivity via smart grid technology. It emphasizes the significance of cybersecurity protocols to safeguard photovoltaic infrastructure and promotes legislative and regulatory enhancements to facilitate resilience implementation. Collaboration among researchers, industry executives, and policymakers is considered crucial for addressing the increasing difficulties presented by climate change. This paper establishes a framework for integrating resilience into all facets of solar PV system design and operation, thereby ensuring the long-term sustainability, efficiency, and efficacy of solar energy systems in a swiftly changing climate environment. This comprehensive strategy is essential for ensuring the future of renewable energy amid global environmental difficulties.
Spatial analysis of leachate penetration at Lemna dumpsite, Calabar: Implications for sustainable waste management in Cross River State
(Elsevier B.V. : Amsterdam, 2024) Igelle, Evaristus Idaga; Phil-Eze, Philip Ogbonnia; Akim, O. Okang; Kanu, H. Izuakolam; Ekwok, I. C.; Atsa, Joy William Undie; Ojugbo, P. A.; Okputu, Joseph S.; Abdelrahman, Kamal; Ekwok, Stephen Eguba; Andráš, Peter; Eldosouky, Ahmed Mohammed
This study rigorously investigated the spatial analysis of leachate penetration at Lemna dumpsite, located in Calabar, Cross River State, Nigeria. Purposeful soil sampling, performed at specific intervals (5 m, 25 m, and 50 m) along the Electrical Resistivity profile line within the dumpsite, was augmented by water sample collection from five boreholes near Lemna dumpsite. Utilizing Electrical Resistivity Tomography (ERT) and Vertical Electric Sounding (VES) survey techniques, resistivity data were systematically gathered to comprehensively analyze the Leachate Penetration in the Lemna dumpsite. Laboratory analysis of soil and borehole water quality focused on Benzene, Toluene, Ethylbenzene, and Xylene (BTEX), with paired sample t-tests applied for statistical scrutiny. Analyzing the ERT and VES data employed sophisticated techniques embedded in Resistivity Two Dimension Invasion software and Advanced Geosciences Incorporation Earth Imager software. Substantial disparities (p < 0.05) emerged in the paired sample t-tests for BTEX in soil compared to National Environmental Standard Regulation and Enforcement Agency (NESREA) limits. Similarly, BTEX in borehole water displayed significant differences (p < 0.05) when compared to World Health Organization (WHO) standards, raising alarming concerns about the safety and portability of groundwater in the area. The examination of dumpsite leachate penetration revealed a resistivity anomaly of 8.01 Ωm and an inverse depth of 12.4 m, underscoring profound environmental implications and necessitating immediate remediation efforts. Additionally, Vulnerability and Aquifer Protective Capacity Index (VES) results, with a rating of <0.1, indicated severely compromised aquifer protective capacity, emphasizing the vulnerability of groundwater resources to further contamination. Our study advocates for strategic management, remediation, and monitoring measures to prevent contamination and safeguard water quality in the region.
The role of phytohormones in phytoremediation using reed
(North University of Baia Mare, 2025) Kočířová, Jana; Nováková, Jana; Plačková, Lenka; Melčáková, Iva; Hekera, Petr; Stalmachová, Barbara; Andráš, Peter; Doležal, Karel
Salinity is a global problem and salinity areas are constantly increasing because of poor-quality irrigation systems containing high concentration of dissolved salts, salt penetration, and water pollution. This study deals with the phytoremediation of salts from mine water using phytohormones auxin 1-naphthylacetic acid (NAA) and cytokinin (m-topolin) at a concentration 10-5 mol/l and common reed (Phragmites australis). The reed plants collected at the Lazy Mine were tested for their ability to accumulate salts from the surrounding mine waters. The experiment was carried out under controlled and controllable conditions in a phytotron. The hypothesis to be tested was a positive effect of phytohormones on the ability of the common reed to better accumulate salts from mine wastewater. The results show that the application of phytohormones in the long-range period, especially auxin, at a concentration of 10-5 mol/l could have a positive effect on the ability of reeds to accumulate salts from mine waters.
Unveiling the mineral resources and structural patterns in the Middle Benue Trough: a comprehensive exploration using airborne magnetic and radiometric data
(Taylor & Francis Group : Abingdon, 2024) Ekwok, Stephen Eguba; George, Anthony M.; Omori, Asuquo A.; Abdelrahman, Kamal; Ugar, Samuel Izama; Andráš, Peter; Morphy, Morod Iwong; Akpan, Anthony E.; Eldosouky, Ahmed Mohammed
The Middle Benue Trough (MBT) in Northcentral Nigeria is a geologically significant area with vast mineral resource potential. Employing airborne magnetic and radiometric data, this study utilized the Centre for Exploration Targeting on enhanced total magnetic intensity data to reveal geologic structures, lithological units and mineralization zones. Lineaments predominantly trended in NE-SW direction, with noteworthy orientations in NNE-SSW and E-W. Radiometric anomalies correlated with distinct lithological units, pinpointing granitic gneiss, alluvium, shale, siltstone and sandstone. A magnetically concentrated and potassium-rich area indicated potential polymetallic-magnetic mineralization. The 2D model illustrated igneous intrusions influencing prevalent geologic structures, such as sediment baking and doming. Thorough analysis, including source parameter imaging, standard Euler deconvolution and 2D forward modelling, revealed sediment thicknesses below 1500 m. This research enhances understanding of the MBT’s geological features, offering valuable insights for mineral exploration and resource assessment in the region.

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