Search Results (183)

During a volcanic eruption, a large volume of pyroclastic material can be deposited on the roads and roofs of the urban areas near volcanoes. The use of volcanic ash as an additive for the manufacture of bricks provides a solution to the disposal of part of this natural residue and reduces the depletion of a non-renewable natural resource, clayey soil, which brings some environmental and economic advantages. The pore system, compactness, uniaxial compression strength, thermal conductivity, color and durability of bricks without and with the addition of volcanic ash were evaluated through hydric tests, mercury intrusion porosimetry, ultrasound, uniaxial compression tests, IR thermography, spectrophotometry and salt crystallization tests. The purpose of this research is to determine the feasibility of adding 10, 20 and 30% by weight of volcanic ash from La Palma (Canary Islands, Spain) in two grain sizes to produce bricks fired at 800, 950 and 1100 °C. The novelty of this study is to use two sizes of volcanic ash and fire the samples at 1100 °C, which is close to the liquidus temperature of basaltic magmas and allows a high degree of interaction between the volcanic ash and the brick matrix. The addition of fine volcanic ash was found to decrease the porosity of the bricks, although the use of high percentages of coarse volcanic ash resulted in bricks with almost the same porosity as the control samples. The volcanic ash acted as a filler, reducing the number of small pores in the bricks. The presence of vesicles in the volcanic ash reduced the compressive strength and the compactness of the bricks with additives. This reduction was more evident in bricks manufactured with 30% of coarse volcanic ash and fired at 800 and 950 °C, although they still reached the minimum resistance required for their use in construction. No significant differences in thermal conductivity were noticed between the bricks with and without volcanic ash additives, which is crucial in terms of energy savings and the construction of sustainable buildings. At 1100 °C the volcanic ash changed in color from black to red. As a result, the additive blended in better with the matrix of bricks fired at 1100 °C than in those fired at 800 and 950 °C. The bricks with and without volcanic ash and fired at 1100 °C remained intact after the salt crystallization tests. Less salt crystallized in the bricks with volcanic ash and fired at 800 and 950 °C than in the samples without additives, although their low compressive strength made them susceptible to decay. Full article

To achieve a significant breakthrough in the exploration of uranium resources in the Guangzitian area of northern Guangxi, China, an innovative combination of exploration methods was implemented at the peripheral regions of the Guangzitian uranium deposit under the guidance of the following principle: “exploring the edges and identifying the bottom, delving deep and un-covering blind spots”. This study introduces geo-electrochemical integrated technology for prospecting research at the peripheral areas of the Guangzitian deposit. By validating the technology’s effectiveness on known geological sections, distinct geo-electrochemical extraction anomalies were identified above recognized ore bodies. Simultaneously, soil ionic conductivity and thermally released mercury anomalies were observed, partially indicating the presence of concealed uranium deposits and fault structures. These findings demonstrate that geo-electrochemical integrated technology is effective in detecting buried uranium mineralization in this region. Subsequently, a geological-geoelectrical prospecting model was established through a systematic analysis of anomaly characteristics and metallogenic regularity, and it was subsequently applied to unexplored areas. As a result, one key anomaly verification zone, one Class A comprehensive anomaly zone, two Class B comprehensive anomaly zones, and one Class C comprehensive anomaly zone were identified within the unexplored research area. Drilling engineering validation was conducted in the No. Ι key anomaly verification zone, resulting in the discovery of an industrial-grade uranium ore body. This achievement not only provides critical technical support but also develops a robust theoretical foundation for future mineral exploration endeavors. Full article

Soil potentially toxic element (PTE) contamination remains a global concern, particularly in rural agricultural regions. This study collected 157 agricultural topsoil samples within a rural area in SW China. Combined with multivariate statistical analysis in the compositional data analysis (CoDa) perspective, the PMF model was applied to identify key contamination sources and quantify their contributions. Potential ecological risk assessment and Monte Carlo simulation were employed to estimate ecological-health risks associated with PTE exposure. The results revealed that the main exceeding PTEs (Mercury—Hg and Cadmium—Cd) are rich in urbanized areas and the GFGP (Grain for Green Program) regions. Source apportionment indicated that soil parent materials constituted the dominant contributor (32.48%), followed by traffic emissions (28.31%), atmospheric deposition (21.48%), and legacy agricultural effects (17.86%). Ecological risk assessment showed that 60.51% of soil samples exhibited higher potential ecological risk (PERI > 150), with moderate-risk areas concentrated in the GFGP regions. The elements Cd and Hg from legacy agricultural effects and atmospheric deposition contributed the most to ecological risk. Health risk assessment demonstrated that most risk indices fell within acceptable ranges for all populations, while only children showed elevated non-carcinogenic risk (THI_max > 1.0). Among PTEs, the element As, mainly from traffic emissions, was identified as a priority control element due to its significant health implications. Geospatial distributions showed significant risk enrichment in the GFGP regions (legacy agricultural areas). These findings present associated risk levels in sustainable agricultural regions, providing valuable data to support soil environmental management in regions requiring urgent intervention worldwide. Full article

Highly over-mature marine shales are distributed worldwide with substantial resource potential, yet their pore structure characteristics and controlling mechanisms remain poorly understood, hindering accurate shale gas resource prediction and efficient development. This study focuses on the Cambrian Niutitang Formation shales in the Upper Yangtze region of South China. To decipher the multiscale pore network architecture and its genetic constraints, we employ scanning electron microscopy (SEM) pore extraction and fluid intrusion methods (CO₂ and N₂ adsorption, and high-pressure mercury intrusion porosimetry) to systematically characterize pore structures in these reservoirs. The results demonstrate that the shales exhibit high TOC contents (average 4.78%) and high thermal maturity (average Ro 3.64%). Three dominant pore types were identified: organic pores, intragranular pores, and intergranular pores. Organic pores are sparsely developed with diameters predominantly below 50 nm, displaying honeycomb, slit-like, or linear morphologies. Intragranular pores are primarily feldspar dissolution voids, while intergranular pores exhibit triangular or polygonal shapes with larger particle sizes. CO₂ adsorption isotherms (Type I) and low-temperature N₂ adsorption curves (H3-H4 hysteresis) indicate wedge-shaped and slit-like pores, with pore size distributions concentrated in the 0.5–50 nm range, showing strong heterogeneity. Pore structure shows weak correlations with TOC and quartz content but a strong correlation with feldspar abundance. This pattern arises from hydrocarbon generation exhaustion and graphitization-enhanced organic pore collapse under high compaction stress, which reduces pore preservation capacity. The aulacogen tectonic setting engenders proximal sediment provenance regimes that preferentially preserve labile minerals such as feldspars. This geological configuration establishes optimal diagenetic conditions for the subsequent development of meso- and macro-scale of dissolution pores. Our findings demonstrate that feldspar-rich shales, formed in a proximal depositional system with well-developed inorganic pores, serve as favorable reservoirs for the exploration of highly over-mature marine shale gas. Full article

Although Mercury Intrusion Porosimetry (MIP) and Nuclear Magnetic Resonance (NMR) are widely used for pore characterization, their effectiveness is fundamentally constrained by theoretical limitations. This study investigated the pore structure characteristics of coal-bearing sandstones from the northeastern Ordos Basin using an integrated approach combining experimental measurements and model-based inversion. The experimental measurements comprised a stress-dependent acoustic velocity test (P- and S-wave velocities), X-ray diffraction (XRD) mineralogical analysis, and NMR relaxation T₂ spectra characterization. For model-based inversion, we developed an improved Mori-Tanaka (M-T) theoretical framework incorporating stress-sensitive pore geometry parameters and dual-porosity (stiff/soft) microstructure representation. Systematic analysis revealed four key findings: (1) excellent agreement between model-inverted and NMR-derived total porosity, with a maximum absolute error of 1.09%; (2) strong correlation between soft porosity and the third peak of T₂ relaxation spectra; (3) stiff porosity governed by brittle mineral content (quartz and calcite), while soft porosity showing significant correlation with clay mineral abundance and Poisson’s ratio; and (4) markedly lower elastic moduli (28.78%–51.85%) in Zhiluo Formation sandstone compared to Yan’an Formation equivalents, resulting from differential diagenetic alteration despite comparable depositional settings. The proposed methodology advances conventional NMR analysis by simultaneously quantifying both pore geometry parameters (e.g., aspect ratios) and the stiff-to-soft pore distribution spectra. This established framework provides a robust characterization of the pore architecture in Jurassic sandstones, yielding deeper insights into sandstone pore evolution within the Ordos Basin. These findings provide actionable insights for water hazard mitigation and geological CO₂ storage practices. Full article

Plants serve as vital components of ecosystems, with their contamination status acting as sensitive indicators of environmental pollution. Therefore, the precise assessment of plant heavy metal contamination and source identification are crucial for regional ecological conservation and sustainable development. This study investigated heavy metal pollution in four characteristic plant species (Anabasis aphylla L., Alhagi camelorum Fisch., Reaumuria songonica (PalL)Maxim., and Haloxylon ammodendron (C. A. Mey.) Bunge.) within the Kalamaili Mountain Nature Reserve, employing comprehensive methodologies including pollution indices, bioconcentration factors (BCFs), absolute principal component score–multiple linear regression (APCS-MLR), and the random forest model (RF). The key findings revealed the following: The soil exhibited severe Cd and Hg contamination. The plant Cr concentrations exceeded standard limits by 31.89 to 147 fold. The Pb, Hg, and As content in plants showed significant differences. The plants displayed differential metal enrichment capacities, ranked as Cr (BCF = 3.28) > Hg (1.22) > Cd (0.92) > Cu (0.25) > Zn (0.15) > Pb (0.125) > As (0.125), highlighting Cr, Hg, and Cd as priority ecological hazards. Complex interactions were observed, with Reaumuria songonica (PalL)Maxim. showing strong Cd soil–plant correlation (r = 0.78), whereas Alhagi camelorum Fisch. demonstrated negative associations (Cd: r = −0.21). APCS-MLR identified mining/smelting as primary contributors to Cd (63.49%), Zn (55.66%), and Cr (45.51%), while transportation dominated Pb emissions (72.92%). Mercury pollution originated from mixed sources (56.18%), likely involving atmospheric deposition, and RF modeling corroborated these patterns, confirming industrial and transportation synergies for Cd, Zn, Cr, Cu, Hg, and As, with Pb predominantly linked to vehicular emissions. This multidisciplinary approach provides scientific evidence for establishing heavy metal monitoring systems and formulating targeted remediation strategies in arid ecologically fragile regions. Full article

The assessment of air pollution is an important and relevant issue that requires continuous monitoring and control, especially in urban spaces. However, using instrumental air quality measurement techniques and deploying meters throughout the city is extremely expensive, so a biological alternative can be used—a bioindicator, i.e., a species whose vital functions or morphological structure can reveal the qualitative state of the environment. In this work, the lichen Hypogymnia physodes L. was used to analyze air pollution in areas of the provincial city of Opole, southern Poland. Microscope and chemotaxonomy methods were used in the laboratory to confirm field identification of lichens (atlases and keys). The selected elements, Mn, Fe, Ni, Cu, Zn, Cd, and Pb, were determined using atomic absorption spectrometry, and direct mercury analyzer was used to analyzed Hg concentration. Factor analysis (FA) was performed to associate elements with possible sources of air pollution. The highest concentrations of analytes were found at measurement points close to railway roads (Fe = 5131 mg/kg) and streets with heavy traffic (Pb = 101 mg/kg). Statistically significant differences (p < 0.001) were found between the concentrations of individual elements, which have positive correlation coefficients higher than 0.65. Based on the research carried out, different anthropogenic and traffic-related activities can be considered as one of the main sources of air pollution in Opole City based on the results of FA. Using an additional lichen scale, it can be concluded that the areas surveyed in the town of Opole can be classified as zone IV—characterized by an increase in the number of leaf lichens (additionally co-occurring lichens of the Polycauliona candelaria species), i.e., an area with an average level of air pollution (based also on contamination factor [CF] and pollution load index [PLI]). Accumulation concentrations of heavy metals in lichen were metal-specific and varied spatially, thus reflecting local differences in heavy metal deposition. The research presented here proves that low-cost passive biomonitoring can effectively support classical methods of assessing air pollution in urban spaces. Full article

In recent years, the successful application of gravity-flow deposit theory in major petroliferous basins in China had attracted extensive attention in the field of sedimentology and had become a key research frontier. This study utilized core, drilling, logging, and microphotograph data, along with low-temperature nitrogen adsorption and high-pressure mercury injection experiments. It discussed the characteristics of gravity-flow deposits, sedimentary microfacies, sedimentary models, and the significance of gravity-flow deposits to pore heterogeneity in shale reservoirs, focusing on the first submember of the Dongyuemiao Member (referred to as the Dong 1 Member) in the Fuling area of the Sichuan Basin. The results indicated the development of four types of mudrock in the Dong 1 Member: massive to planar laminated shell mudrock (F1), planar laminated bioclastic mudrock (F2), planar laminated silty mudrock (F3), and massive mudrock (F4). These corresponded to debris flow deposits (F1, F2), turbidite deposits (F3), and suspension deposits (F4). According to the characteristics of lithofacies combinations and sedimentary features, four sedimentary microfacies were identified: gravity-flow channel, tongue-shaped, lobate, and semi-deep lake mud. The Shell Banks were disturbed by earthquakes, tides, storms, and other activities. Silt, clay, fossil fragments, plant debris, and other materials were deposited under the influence of gravity, mixing with surrounding water to form an unbalanced and unstable fluid. When pore pressure exceeded viscous resistance, the mixed fluid became unbalanced, and gravity flow began to migrate from the slope to the center of the lake basin. A sedimentary unit of gravity-flow channel-tongue-shaped-lobate was developed in the Fuling area. The Fuling area’s gravity-flow depositional system resulted in distinct microfacies within the Dongyuemiao Member, each exhibiting characteristic lithofacies associations. Notably, lobate deposits preferentially developed lithofacies F3, which is distinguished by significantly higher clay mineral content (60.8–69.1 wt%) and elevated TOC levels (1.53–2.45 wt%). These reservoir properties demonstrate statistically significant positive correlations, with clay mineral content strongly influencing total pore volume and TOC content specifically enhancing mesopore development (2–50 nm pores). Consequently, the F3 lithofacies within lobe deposits emerges as the most prospective shale gas reservoir unit in the study area, combining optimal geochemical characteristics with favorable pore-structure attributes. Full article

Trees mediate critical biogeochemical cycles involving nutrients, pollutants, water, and energy at the interface between terrestrial biosphere and atmosphere. Forest ecosystems significantly influence the global cycling of mercury (Hg), serving as important sinks and potential sources of re-emission through various biotic and abiotic processes. Anthropogenic Hg emissions, predominantly from industrial activities, mining, and fossil fuel combustion, have substantially altered the natural Hg cycle, intensifying ecotoxicological concerns and establishing forests as primary routes for atmospheric Hg deposition into terrestrial reservoirs. This perturbation profoundly affects global atmospheric Hg concentrations, residence times, and spatial distribution patterns. While early investigations focused on forest stands near heavily polluted areas, contemporary research has expanded to diverse ecosystems, revealing that trees provide tissues that function as temporal archives for atmospheric-terrestrial Hg exchange. Leaves capture high-resolution records of contemporary Hg dynamics at sub-annual timescales, whereas annual growth rings preserve multi-decadal chronologies of historical atmospheric exposure. Incorporating this dual temporal perspective is crucial for analysing Hg deposition trends and assessing the efficacy of environmental policies designed to control and mitigate Hg pollution. This review critically evaluates recent developments concerning the ecophysiological determinants of Hg accumulation in trees, highlighting how combined foliar and dendrochemical analytical methods strengthen our mechanistic understanding of vegetation-atmosphere Hg exchange. To enhance biomonitoring approaches, we emphasised the need for methodological standardisation, deeper integration of ecophysiological variables, and consideration of climate change implications as priority research areas. Furthermore, integrating Hg measurements with functional markers (δ¹³C and δ¹⁸O) and Hg isotope analyses strengthens the capacity to differentiate between physiological and environmental influences on Hg accumulation, thereby refining the mechanistic framework underlying effective tree-based Hg biomonitoring. Full article

Mercury (Hg) is a naturally occurring element, but atmospheric Hg has increased due to human activities since the industrial revolution. When deposited in aquatic environments, atmospheric Hg can be converted to methyl mercury (MeHg), which bioaccumulates in ecosystems and can cause neurologic and endocrine disruption in high quantities. While higher atmospheric Hg levels do not always translate to higher contamination in wildlife, museum specimens over the past 2 centuries have documented an increase in species that feed at higher trophic levels. Increased exposure to pollutants presents an additional threat to fish and wildlife populations already facing habitat loss or degradation due to global change. Additionally, Hg cycling and bioaccumulation are primarily driven by geophysical, ecological, and biogeochemical processes in the environment, all of which may be modulated by climate change. In this review, we begin by describing where, when, and how the Hg cycle may be altered by climate change and how this may impact wildlife exposure to MeHg. Next, we summarize the already observed physiological effects of increased MeHg exposure to wildlife and identify future climate change vulnerabilities. We illustrate the implications for wildlife managers through a case study and conclude by suggesting key areas for management action to mitigate harmful effects and conserve wildlife and habitats amid global change. Full article

This study systematically investigates the heterogeneity of the Chang 6 reservoir in the Wuqi–Dingbian region of the Ordos Basin through integrated petrographic analysis using scanning electron microscopy (SEM), thin-section petrography, and mercury intrusion porosimetry. The results reveal that this feldspathic sandstone reservoir exhibits significant compositional and textural variations controlled by depositional environments. Dingbian samples displayed elevated feldspar (avg. 42.3%), lithic fragments (18.1%), and carbonate cementation (15.7%), accompanied by intense mechanical compaction and cementation processes. Pore systems in Dingbian were dominated by residual intergranular pores (58–62% of total porosity) and secondary dissolution pores. In contrast, Wuqi reservoirs demonstrated superior pore connectivity through well-developed intergranular pores (65–72%), grain boundary pores, and microfracture networks. Pore throat characterization revealed distinct architectural patterns: Wuqi exhibited broad bimodal/multimodal distributions (0.1–50 μm) with 35–40% macro-throat (>10 μm) contribution to flow capacity, while Dingbian showed narrow unimodal distributions (1–10 μm) with <15% macro-throat participation. These microstructural divergences fundamentally governed contrasting production behaviors. Wuqi wells achieved higher initial flow rates (15–20 m³/d) with 60–70% water cut, yet maintained stable production through effective displacement systems enabled by dominant macropores. Conversely, Dingbian wells produced lower yields (5–8 m³/d) with 75–85% water cut, experiencing rapid 30–40% initial declines that transitioned to prolonged low-rate production phases. This petrophysical framework provides critical insights for optimized development strategies in heterogeneous tight sandstone reservoirs, particularly regarding water management and enhanced oil recovery potential. Full article

Filtered cathodic vacuum arc (FCVA) deposition technology was applied to prepare tetrahedral amorphous carbon (taC) thin films with different substrate pulse biases. Their structure, adhesion strength, and corrosion behavior in 5 × 10⁻² M hydrochloric (HCl), sodium chloride (NaCl), calcium chloride (CaCl₂), lead (II) chloride (PbCl₂), and mercury (II) chloride (HgCl₂) solutions were studied with respect to the substrate pulse bias. Increasing the substrate pulse bias from 0 to 1000 V increased the graphitization of the taC thin films and thereby resulted in a 9.9% increase in their adhesion strength from 406 mN to 446 mN. The taC thin films exhibited the lowest (8.48 × 10⁴ Ω to 11.55 × 10⁴ Ω) and highest (146.89 × 10⁴ Ω to 387.44 × 10⁴ Ω) corrosion resistance in the PbCl₂ and HgCl₂ solutions, respectively, while they had higher corrosion in the HCl (62.07 × 10⁴ Ω to 131.73 × 10⁴ Ω) solution than in both the NaCl (143 × 10⁴ Ω to 231.31 × 10⁴ Ω) and CaCl₂ (102.13 × 10⁴ Ω to 351.92 × 10⁴ Ω) solutions. Nevertheless, the taC thin films with higher substrate pulse biases had lower corrosion resistance in all the solutions used in this study. The substrate pulse bias emerged as a significant parameter in the FCVA deposition process, playing a crucial role in influencing the structure, adhesion strength, and corrosion resistance of taC thin films. Full article

The study of pore structure in low-permeability sandstone uranium deposits has become a key factor in the profitability of uranium mining. In this paper, pore and fracture distribution in the target sandstone were determined by using mercury injection parameters. Single and multi-fractal models are used to calculate the heterogeneity of pore and fracture volume distribution. Moreover, the correlation between compressibility and the heterogeneity of pore distribution has been studied. The results are as follows. (1) All the samples can be divided into three types by using maximum mercury injection volume and mercury withdrawal efficiency. Type A is represented by a lower maximum mercury injection volume (less than 0.5 cm³·g⁻¹) and a higher mercury withdrawal efficiency (larger than 25%). The volume percentage of pores whose diameter is less than 100 nm and 100~1000 nm in type A samples is larger than that of type B and C samples since in this type of sample, micropores are developed. (2) The fractal dimension value assessed using the Menger model has a good linear relationship with the thermodynamic model, which indicates that the abovementioned models have good consistency in characterizing the pore distribution of tight sandstone. Multi-fractal results show that the lower pore volume in the selected samples controls the heterogeneity of pore distribution in the overall sample. (3) As the effective stress increases, the permeability damage rate gradually increases in a power exponential equation. The correlation between porosity and compressibility is weaker, indicating that only a portion of the pore volume in the sample provides compression space. As the pore volume of 100~1000 nm increases, the compressibility decreases linearly, indicating that pore volumes larger than 1000 nm provide compression space for all the selected samples. Full article

The degradation of concrete caused by sulfate attack poses a significant challenge to its durability. Using nanomaterials to enhance the mechanical and durability properties of concrete is a promising solution. A study of the durability of nano-alumina (NA)-modified concrete by sulfate erosion was carried out. The results showed that the compressive strength, quality, and permeability of concrete to chloride ions decreased during its long-term erosion by a sodium sulfate solution. The NA-modified concrete exhibited higher resistance to erosion by the sodium sulfate than ordinary concrete (OPC), the rate of reduction in its tensile strength was low, and the resistance of sample NA1 to penetration by chloride ions decreased only by one-fifth compared with that of OPC. The results of mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) tests showed that erosion had severely damaged the pore characteristics and micromorphology of concrete. The total porosities of the OPC and NA1 samples increased from 12.68% and 10.29% to 16.03% and 12.71%, respectively. Their microscopic morphology revealed loose particles and poor compactness. The leading causes of damage to concrete due to erosion by the sodium sulfate were its crystallization pressure and the swelling-induced stress caused by the deposition of crystals in its pores. This study demonstrates that NA can significantly enhance the durability of concrete against sulfate attack, offering valuable insights for strategic applications of NA in concrete materials. Full article

This study considers the features of the chemical composition, internal structure, and oscillatory zoning of sulfosalts and sulfates in the epithermal high–intermediate-sulfidation-type Au-Ag-Te Emmy deposit (Khabarovsk Territory, Russia). In Emmy deposit, sulfosalts primarily represent goldfieldite, probably corresponding to a high-sulfidation (HS) mineral association replaced bytennantite–tetrahedrite group minerals. The latter is associated with tellurides and native tellurium, corresponding to an intermediate-sulfidation (IS)-type ore assemblage and suggesting an increasing influx of Te, Sb, and As in the system. Goldfieldite is replaced by native tellurium and tellurides along its growth zones, and is characterized by oscillatory zoning. The replacement of goldfieldite by mercury, nickel, lead, and copper tellurides indicate a new influx of native gold, native tellurium, and gold–silver tellurides into the open mineral-forming system. At deeper levels of the Emmy deposit, an advanced argillic alteration assemblage includes aluminum phosphate–sulfate (APS) minerals, represented by members of the svanbergite–woodhouseite series. Element mapping of the studied APS mineral grains indicated three distinct areas recording the evolution of the hydrothermal system in the Emmy: an oscillatory-zoned margin enriched in sulfur, lead, and barium, corresponding to the late influx of IS state fluids related to gold and tellurides; an intermediate part, which is leached and corresponds to the HS mineralization stage; and the central part of the grains, which is enriched in cerium, calcium, and strontium, resulting from a replacement of magmatic apatite in the pre-ore alteration stage. The leached zone between the core and rim of the APS grains is related to a change in crystallization conditions, possibly due to the mixing processes of the fluids with meteoric water. Barite, found in the upper level of the advanced argillic hypogene alteration assemblage, is also characterized by oscillatory zoning, associated with the enrichment of individual zones in lead. Micron gold particles associated with barite are confined to their lead-enriched zones. The study of fluid inclusions in quartz within the Emmy deposit showed the hydrothermal ore process at a temperature of 236–337 °C. Homogenization temperatures for quartz–pyrite–goldfieldite mineral association vary within 337–310 °C and salinity varies within 0–0.18 wt.%NaCl equivalent, and for gold–silver–telluride–polymetallic mineral association, they decrease and vary within 275–236 °C and salinity slightly increases from 0.18 to 0.35 wt.%NaCl equivalent. This study demonstrates that the nature of oscillatory zoning in sulfosalts and sulfates in the Emmy deposit results from an external process. Such a process is of fundamental importance from a genetic point of view. Full article