The Geologica Macedonica is an international, open access, peer reviewed, both online and printed journal. The journal focuses on the following areas of publication: Mineralogy, Petrology, Geochemistry, Ore deposits, Environmental geochemistry, Hydrogeology, Engineering geology, Geophysics, and other branches of the Earth Sciences.
Geological Institute at the Faculty of Natural and Technical Sciences, University "Goce De
MINERALOGY OF MAGNESITE FROM THE PČINJA RIVER AREA –NORTH MACEDONIA
Magnesite from the Pčinja river area most often occurs in the form of veins of varying thickness and length, with their orientation being determined by the direction of faults and cracks. In certain parts of the terrain, the appearance of multiple subparallel veins is observed, while in other places they cross, branch, or locally disappear and reappear. It appears as microcrystalline mass resembling unglazed porcelain. Its fracture is conchoidal, the hardness is 3½ – 4½, its streak is white and the density is 3.0–3.2 g/cm3. Based on the XRD pattern magnesite is the dominant crystalline phase. The unit cell parameters obtained using the main reflection lines of X-ray diffraction are: a = b = 4.63±0.002 Å, c = 15.02±0.003 Å, V = 279.35 Å3. In addition to magnesite, the presence of serpentine, dolomite and talc has also been determined. The absence of a pronounced basal reflection near 12° indicates that serpentine is not the dominant phase. Dolomite fits into the genesis as an indicator of the early phase of carbonization, and this is genetically very significant. During the initial carbonization of serpentinite, CO₂-rich fluids react with serpentine which also contains Ca (taken from pyroxenes). While Ca is still available in the system, Ca-Mg carbonate is formed dolomite. This occurs at relatively higher temperatures (~350°C). When Ca is depleted from the system (excreted by fluids), reactions continue only with Mg pure magnesite is formed. At the same time, Si released from the serpentine reacts with Mg and water to give talc. This occurs at lower temperatures (~280°C). The dolomite in the examined samples indicates that carbonization has proceeded quite far. Most of it has already been converted to magnesite, and only a small relict amount remains. The serpentine is present but nearly consumed. The Pčinja river area represents an advanced stage of carbonization, where CO₂-rich hydrothermal fluids have converted ~85–90% of the original serpentinite to magnesite, with only isolated relic patches of serpentine surviving. This is entirely consistent with Type I cryptocrystalline magnesite deposits of the Balkan ophiolitic belt.
magnesite; serpentine; ultrabasic rocks; Pčinja river
SEISMOGEOLOGICAL EFFECTS OF STRONG EARTHQUAKES (ML ≥ 6.0) AT THE TERRITORY OF THE REPUBLIC OF NORTH MACEDONIA
Earthquakes are natural processes that, depending on their magnitude, can generate significant seismogeological effects on the Earth's surface as well as within the shallow subsurface environment. This paper focuses on the identification and analysis of seismogeological effects caused by strong earthquakes with magnitudes ML ≥ 6.0, whose epicenters are located within the territory of the Republic of North Macedonia. The study considers the consequences of earthquake activity, including the activation of faults, landslides, soil liquefaction, ground cracks, and changes in hydrogeological conditions. Particular emphasis is placed on the relationship between the geological structure, lithological characteristics, and local site conditions, and their influence on earthquake intensity and the spatial distribution of the observed effects. Based on seismological data and geological indicators, this research highlights the importance of seismogeological investigations for seismic risk assessment and geohazard evaluation. The obtained results are of considerable importance for spatial planning and for reducing the potential impacts of future earthquakes.
earthquake; intensity; seismogeological effects
INFLUENCE OF STRUCTURAL-GEOLOGICAL PROPERTIES IN DETERMINATIONOF ENGINEERING-GEOLOGICAL QUASI-HOMOGENEOUS ZONES WITHIN AMONOLITHOLOGICAL ENVIRONMENT AT THE “OTINJA” DAM SITE
This study presents the results from research of influence of structural-geological properties for defining engineering-geological quasi-homogeneous zones within the monolithological granite environment of the Otinja dam site. For this purpose, a series of field investigations and tests were carried out, which consisted of detailed geological mapping of the foundation pits and core from exploratory boreholes, as well as sclerometer tests of the rock. In addition, cadastres of discontinuities and sclerometer tests were formed. Based on a detailed analysis of obtained data, four quasi-homogeneous zones were distinguished within the granite massif. In addition, the excavation conditions for each of these quasi-homogeneous zones were defined. By preparing engineering-geological maps and profiles, their representation on the surface and in depth was defined. By analyzing fracturing contour diagrams, the influence of dominant fracture systems in different parts of the terrain was determined. It has been concluded that the greatest influence on the fracturing degree is exerted by the faults on the right flank of the dam site, where five different fracturing systems are present. It has also been determined that the degree of fracturing in zones with leucocratic granites is significantly lower.
mapping; discontinuities; cadaster; classification; sclerometer; excavation
MORPHOLOGICAL AND CHEMICAL CHARACTERISTICS OF NATIVE GOLD FROM DETRITAL ENVIRONMENTS: IMPLICATIONS FOR TRANSPORT AND SOURCE PROXIMITY
In this study, an integrated morphological and chemical analysis of native gold from alluvial deposits was conducted in order to determine the relationship between grain morphology, chemical composition, and the distance from the primary gold source. The investigation was carried out using scanning electron microscopy (SEM), whereby the morphology, surface texture, and microstructural characteristics of the gold grains were analyzed, along with their chemical composition (Au, Ag, and Fe). The results indicate significant variability in Au (88.73–99.53 wt.%) and Ag (0.47–9.19 wt.%) contents, whereas Fe is present only in trace amounts. A clear trend of increasing gold fineness with decreasing silver content is observed. Morphologically, the analyzed gold aggregates are predominantly characterized by irregular and angular forms, indicating limited transport and close proximity to the primary source. In addition, grains exhibiting flattened, lamellar, and rounded morphologies are present, which are typical of more distal positions relative to the primary environment. The obtained results confirm that the application of SEM-based morphological and chemical analyses represents a valuable approach for determining transport distance and for assessing the location of primary gold-bearing sources.
RADON (222Rn) AND RADIUM (226Ra) ACTIVITY AND DOSE ASSESSMENT IN SPRING WATERS OF KOSOVO
Radon (²²²Rn) and radium (²²⁶Ra) are naturally occurring radionuclides of the ²³⁸U decay series that may contribute to public exposure through drinking water and indoor air due to radon degassing during household water use. Six springs were sampled and analyzed using the pulse-counting ionization chamber (alpha spectroscopy). method with an AlphaGUARD DF2000 monitor coupled to an AquaKIT system. Radon activity concentrations ranged from 0.06 to 10.88 Bq L⁻¹, while ²²⁶Ra, indirectly determined after a 30-day decay period of radon, ranged from 0.12 to 0.32 Bq L⁻¹. The total committed effective dose for adult consumers (inhalation and ingestion; 222Rn+226Ra) ranged from 14.35 to 59.72 µSv y⁻¹, remaining well below the WHO reference level of 100 µSv y⁻¹. The results indicate no significant radiological risk and contribute to the existing baseline data on radon and radium in spring waters of Kosovo.
radon; radium; spring water; AlphaGUARD; Kosovo
ECOLOGICAL RISK ASSESSMENT OF SOIL CONTAMINATION BY POTENTIALLYTOXIC ELEMENTS. CASE STUDY: MITROVICA REGION, REPUBLIC OF KOSOVO
This study aimed to investigate the input of various potentially toxic elements (Ag, Pb, Sb, Bi, Zn, Cd, As, Cu, Hg, Au, Tl, and Mo) into the surface soils of the Mitrovica region, a historically active Pb–Zn mining and metallurgical area in Kosovo. Geochemical analyses and multivariate statistics revealed a strong contamination pattern resulting from anthropogenic inputs of these elements. An ecological risk assessment of soil contamination by these potentially toxic elements was conducted in this region using various indicators. The contamination factors showed extremely high values for Au, Pb, Sb, Cd, As, and Ag compared to European and global background values, indicating very high to extreme soil contamination. The enrichment factors confirmed significant to extremely high enrichment for most elements except Mo and Tl. The geo- аccumulation indexes indices categorized soil as moderately to extremely contaminated, especially for Pb, Ag, As, Bi, Cd, and Zn. The values of both indicators show highly to extremely contaminated soils with most of the analyzed elements, particularly in the cities of Zveçan and Mitrovica. The cumulative ecological risk index was more than thirty times higher than the critical threshold, indicating a serious threat to soil quality and ecological health.
soil; potentially toxic elements; pollution; ecological risk; Mitrovica region; Republic of Kosovo
CRUSTAL STRUCTURE BENEATH REPUBLIC OF NORTH MACEDONIA BASED ON RECEIVER FUNCTION ANALYSIS
Teleseismic waveforms recorded by Wideband Ranger WR-1 seismometers at three permanent stations of the Seismological Network of the Republic of North Macedonia: Skopje (SKO), Valandovo (VAY) and Ohrid (OHR), were analyzed using the P receiver function method, which enables identification of major seismic discontinuities within the crust and upper mantle below the seismological stations. Аnalysis of the data revealed variations in the timing of the Ps phases, indicating heterogeneity in Moho depth across the region. Specifically, Ps phases were observed between 4,0 and 4,5 seconds after the incident P arrival at the seismological station Skopje (SKO), between 3,5 and 4,5 seconds at the seismological station Valandovo (VAY), and between 5,0 and 5,5 seconds at the Ohrid (OHR) seismological station. To determine the crustal structure, an inversion of the obtained receiver functions was performed using a linearized iterative technique to derive 1-D seismic velocity models of the crust. The inversion results reveal significant variations in crustal thickness, with Moho depths ranging from approximately 34–36 km beneath the Valandovo (VAY) seismological station in the east to over 42–44 km beneath the Ohrid (OHR) seismological station in the west. At the Skopje (SKO) seismological station, the Moho depth is around 36 km. These results provide new constraints on the lithospheric structure of our country and offer valuable insights into the complex tectonic framework of the region.
receiver function; crustal structure; Moho depth
ASSESSMENT OF HEAVY METAL ACCUMULATION IN MOSS SPECIES AS BIOMONITORS OF ATMOSPHERIC POLLUTION IN THE GOLESH FE–NI MINING AREA, REPUBLIC OF KOSOVO
The study aimed to assess the level of air pollution by heavy metals in the area around Golesh, near the iron–nickel (Fe–Ni) mines, using mosses as biomonitors (Homalothecium lutescens (Hedw.) Robins. At 20 selected sampling sites in this area, concentrations of 17 chemical elements were analyzed using the inductively coupled plasma with mass spectrometry (ICP–MS). This study assessed the elemental content, distribution, and level of heavy metal pollution in moss samples, serving as bioindicators in a potentially contaminated area. Statistical analysis revealed wide variations in metal concentrations, with elements such as Al, Fe, and Mg showing the highest average values. The Contamination Factor (CF) revealed extremely high levels of pollution for Cr, Cd, Co, Pb, and Ni, indicating a significant anthropogenic impact. Factor Analysis and Cluster Analyses confirmed the co–occurrence of toxic elements (As, Pb, Ni, Cd) likely originating from industrial and mining activities. The Pollution Load Index (PLI) also highlighted the overall high contamination status of the area. These findings confirm the presence of local pollution sources and reinforce the usefulness of mosses as biomonitors in environmental assessment.
mosses; heavy metal; mining Fe–Ni; ICP–MS
MOSSES AS A BIOINDICATOR OF AIR POLLUTION ALONG THE LEPENC RIVER IN THE REPUBLIC OF KOSOVO
This study investigates the distribution and potential impact of heavy metals: cadmium, cobalt, chromium, copper, iron, nickel, lead, and zinc, in moss samples collected from 20 sites along the Lepenc river in Kosovo, by using Inductively Coupled plasma atomic emission spectroscopy (ICP-AES). Statistical analysis (minimum, maximum, mean, median, etc), cluster analysis, principal component analysis (PCA) and pollution indices (Contamination Factor and Pollution Load Index) were performed to better explain the data of metals concentrations in the moss samples. Low levels of contamination were recorded in samples from the Brezovica area, a mountainous area with minimal anthropogenic influence. Samples from the Kaçanik area were notably enriched in Fe, Pb, Zn, Cd, Cr, and Co, possibly reflecting the influence of vehicular emissions, urban dust, and ongoing construction activities. The highest contamination levels were observed in samples 19 and 20, collected from the industrial region of Hani i Elezit. These samples exceeded critical contamination factor (CF) thresholds for multiple elements (Cd, Co, Cr, Ni, and Pb), marking them as pollution hotspots. Furthermore, pollution load index (PLIzone) for entire area was 5.7, confirmed significant pollution at these study locations. These findings underscore the urgent need for targeted environmental monitoring and pollution mitigation strategies, particularly in urbanized zones such as Ferizaj and in industrial centers like Hani i Elezit and Kaçanik.
heavy metals; mosses; bioindicators; pollution load index (PLI); principal component analysis (PCA)
OCCURRENCE AND MINERALOGICAL CHARACTERIZATION OF SPECULARITE IN DAMJAN ORE DEPOSIT, NORTH MACEDONIA
In this paper are presented occurrence and mineralogical characterization of specularite from Damjan ore deposit. The straightforward identification of the studied mineral sample was enabled by SEM-EDS, XRF and XRPD methods. With these methods it can be seen that the phases present are calcite, specularite and quartz. Specularite crystals occur in the surface parts of the deposit. Specularite has a metallic gray to silvery appearance with a glittering luster and reddish streak. It shows a very smooth surface with reflection. The metallic luster is a result of the specific crystal formation of hematite. Manganese and aluminium substitute for Fe³⁺ in the specularite structure. Small amounts of Fe²⁺ and Mn2+ substitute for Ca²⁺ in the crystal lattice on calcite. The well-developed morphology of specularite suggests that it crystallized first. The finer-grained calcite likely formed later, filling the interstitial spaces between the earlier-formed specularite.
DYNAMICS LAGOON MODELING USING DETAILED TIME-SERIES DIGITAL TERRAIN MODEL
A lagoon is a natural feature formed at the mouth of a river due to the dynamics of river sedimentation, currents, vertical deformation, waves, and tides. Lagoons are dominated by soft soil, so their topography is dynamic. Segara Anakan Lagoon (SAL) is an area that experiences dynamic topography caused by rapid sedimentation. Changes in the dynamics of the delta topography can be tracked in the past with the Digital Terrain Model (DTM) time series extracted from the latest DTM, vertical deformation, and sedimentation data. The observation period was 1978–2021. This study aims to model topography dynamics (1978–2021) in SAL according to DTM, vertical deformation, and sedimentation data. This dynamics topography modeling uses (1) parameters of sedimentation rate and volume obtained from river basin center – Balai Besar Wilayah Sungai (BBWS) 2012, (2) DTM 2021 extracted from ALOS-2 (2017) and integrated with vertical deformation from Sentinel-1 (2017–2021) using the Differential Interferometry Synthetic Aperture Radar (D-InSAR) method. The DTMs (1978, 1991, 2001, and 2010) are extracted using a geospatial forensics approach based on topography modeling of DTM 2021, vertical deformation (2017–2021), and rapid sedimentation data. We use the sediment rate entering SAL from the Citanduy River (8.05 million tons/year), Cimeneng River (0.87 million tons/year), and Cikonde River (0.22 million tons/year), with a total sediment supply of 9.14 million tons/year. The DTM 2021 has a spatial resolution of 1 m and has been validated in its vertical accuracy test (+17.6 cm) and its height difference test (~0 m) with a confidence level of 95 % (1.96 σ). The average vertical deformation value is –0.0240 to –0.0320 m. The results obtained are dynamics topography information (1978–2021). The DTMs (1978–2021) visualize dynamics topography changes in SAL. They are carried out by checking the dynamics of shoreline changes and cross-section profiles to determine the suitability of shapes and patterns (lagoon and delta). Sedimentation is the most significant parameter that influences the topography dynamics in SAL.
DTM and vertical deformation; dynamic lagoon; SAL; dynamics topography; rapid sedimentation
ISOTOPIC COMPOSITION OF SULFUR IN THE BOROV DOL DEPOSIT, NORTH MACEDONIA
The study of the isotopic composition of sulfur is essential for the development of genetic models of porphyry copper deposits. In order to determine the origin of metals and sulfur in the Borov Dol porphyry copper deposit, a series of research and analyses of sulfur isotopes (32S, 34S) and their isotopic ratio (d³⁴S) were conducted. Samples were taken at the Borov Dol deposit, mainly of pyrite (from the hydrothermal temperature range of 250–350ºC), then chalcopyrite, galena, sphalerite, and chalcocite. At the Borov Dol deposit, the values show a wide range starting from –7.25‰ to +5.40‰ d³⁴S, with an average of –0.38‰ d³⁴S. Accordingly, the source of the sulfur is mag­matic, associated with the deep parts of the Earth's crust or with the boundary zone between the continental crust and the upper mantle, with intrusive fractionation and partial enrichment with the light sulfur isotope, which is reflected in the negative value in the higher levels of the deposit, or in the slight enrichment of the heavy sulfur isotope, which is reflected in the positive value in the lower levels of the deposit. The sulfide parageneses in the Borov Dol porphyry system were most likely deposited from oxidized hydrothermal ore-bearing solutions, whereby there is no equilibrium in the system during the crystallization of the early-stage paragenesis. The equilibrium in the system is established during the crystallization of the paragenesis in the middle and late stages.
sulfur isotopes; ore minerals; composition; fractionation; Borov Dol deposit
CARBON AND OXYGEN ISOTOPE SIGNATURE OF HYDROTHERMAL MINERAL DEPOSITS IN A POST-COLLISIONAL MAGMATIC-HYDROTHERMAL SYSTEM: A REVIEW FROM NORTH MACEDONIA
The subaerial magmatic-hydrothermal system exposed on the territory of Republic of North Macedonia represents a natural laboratory for studies of ore-forming processes associated with post-collisional magmatism. In this part of the Balkan Peninsula, neotectonics uplifted and exposed Tertiary post-collisional mineral deposits formed at different crustal levels, including deeply sitting porphyry Cu deposits, proximal and distal skarn deposits, and Carlin-like deposits. Locally epithermal deposits are also preserved. This paper summarizes and discusses previously published carbon and oxygen isotope data obtained from gangue carbonates collected from the key deposits in North Macedonia.
carbon; oxygen; isotope; hydrothermal; North Macedonia
SPATIAL DISTRIBUTION OF THALLIUM IN THE SOILS OF NORTH MACEDONIA
The aim of the study was to determine the spatial distribution and assessment of thallium contam- ination in the soils of North Macedonia. Topsoil samples (0–30 cm) were collected from 995 locations throughout the country in a grid of 5×5 km between sampling points. The soil samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using the total digestion method. The distribution of thallium in the soils according to the eight statistical regions of the country is discussed, as well as the distribution based on the 15 most common geological formations and the distribution based on 13 pedological units. The thallium content varied in Macedonian soils from <0.05 to 15.5 mg/kg (median 0.70 mg/kg), which corresponds to the total Tl content for the European soils with a range of 0.01 to 21.3 mg/kg and a median of 0.66 mg/kg. The spatial distribution patterns of Tl in the collected soil samples are mainly determined by the geology (parent material and mineralization). In some areas, the natural anomaly pattern is overlaid by anthropogenic emissions from past and present mining, ore processing and associated metal industries.
thallium; soil; spatial distribution; North Macedonia
ARSENIC, HEAVY METALS AND RARE EARTH ELEMENTS IN TRAVERTINE LIMESTONE QUARRY IN THE MARIOVO AREA, NORTH MACEDONIA
Travertines in the Mariovo area are an extremely important raw material for obtaining architectural and decorative stone used in construction. In this region, there are six locations where travertine is exploited and this paper presents the results obtained from the mineralogical and geochemical tests of samples taken from the Mariovo travertines. The tests performed show that these are relatively young sedimentary rocks that are basically made of calcite, and in which the concentration of arsenic and heavy metals is extremely low. This finding supports the further use of these rocks as architectural and decorative stone.
аrsenic; rare earth elements; travertine; Mariovo
ANALYSIS OF DISCRETIZATION ERRORS IN MICROTREMOR MEASUREMENTS
This study investigates the effects of discretization errors on the analysis of microtremor vibrations measured in a building located in Berovo, using the EQR120 accelerometer. The primary focus is on the impact of discretization on Fourier spectral amplitudes and the accuracy of frequency domain analysis. The results show that with increasing recording time (T), there are more pronounced peaks in the Fourier spectrum, especially for higher frequencies. Despite variations in discrete levels of acceleration, the frequency domain response of the instrument remains nearly constant over a wide range of frequencies, resembling white noise. The study highlights that microtremor amplitudes are generally small, and significant variations in spectral amplitudes were not observed over time in a 24 hour measurement period. The findings suggest that external excitation with larger forces is needed to observe spectral peaks, particularly in the ground floor movements. The analysis provides valuable insights into the behavior of microtremors in built environments and emphasizes the challenges of capturing small-scale vibrations in densely populated areas.
discretization; microtremors; Fourier spectrum; measurement accuracy; building vibrations
COMPARATIVE ASSESSMENT OF WATER QUALITY FOR IRRIGATION IN THE KARST AREA OF THE RIVER BASIN OF SLATINSKA REKA
This study used available hydrochemistry data to determine the suitability of water bodies in the lower karst area in the river basin of Slatinska Reka for irrigation. Surface rivers Krušeska Reka, Markoska Reka (two points), and Slatinska Reka, as well as the springs Slatinski Izvor and Solenica, were observed between December 2011 and November 2013, and water samples were taken from each point. Irrigation quality parameters, such as Sodium Absorption Ratio (SAR), Sodium Percentage (Na%), Magnesium Adsorption Ratio (MAR), Kelly Ratio (KR), and Total Hardness (TH), were analyzed for suitability for irrigation. All analyzed parameters pointed out that surface rivers and the karst spring Slatinski Izvor were suitable for irrigation, whereas most of the water samples taken from the Solenica spring were not suitable for irrigation purposes. Also, the Solenica spring downstream of Markoska Reka influenced the irrigation properties of the river water, especially during the low waters. The process of karstification had a significant impact on the chemical composition of the water in the basin.
irrigation water quality; river basin of Slatinska Reka;l karst area
GEOHAZARD PHENOMENON INDUCED BY SALT EXPLOITATION AND APPLIED NEW METHODS FOR MONITORING GROUND SURFACE MOVEMENTS
The subsidence occurring in the city of Tuzla in Bosnia and Herzegovina (B&H) is an important issue which has caused several damages in the past decades. This phenomenon is related to the massive extraction of salt and the presence of salt caverns below the city. The salt mine was closed between 2006 and 2007 by means of filling the salt mine rooms with water, but the subsidence still continues over some parts of the city. This paper presents geohazard phenomenon caused by the exploitation of the salt mine in Tuzla, as well as the interpretation of the monitoring results of subsidence measured by new satellite technology together with the previous results, i.e., 2004 – 2007 by GPS, 2013 – 2024 by GPS, 2014 – 2019 by DInSAR technology, and 2019 – 2024 by DInSAR from authors. The time transition for the subsidence obtained by DInSAR shows a good agreement with the monitoring results by GPS. It is found that the subsidence in Tuzla is still on-going at a rate of 1 – 2 cm/year in the measured points of salt deposit, while point number 16 and its surroundings currently have greater subsidence compared to the remaining part of the Tuzla salt deposit. This paper concludes that DInSAR technology has proven to be an excellent method for monitoring the subsidence of the terrain at the city of Tuzla and would represent an accurate and reliable approach for monitoring similary affected areas.
geohazard phenomenon; salt mine; subsidence; monitoring; GPS; SBAS-DInSAR