Geological Survey of Iran

In this work, the volume of sample solution and concentration of gold was optimized for extraction with foam in dimensions (1 × 1 × 1) and then was used for extraction from soil samples. The results showed that the proposed technique has a good analytical efficiency compared to the standard fire assay method and the accuracy of work is in the range of 74–125 %. The equation of linear calibration curve was obtained with regression coefficient better than 0.9997, and the detection and quantification limit of the gold in aqueous and soil sample obtained 0.25 and 0.8 µg kg ⁻¹, respectively.•This method is inexpensive and fast for determination of gold in various samples. •This method has high thought of sample determination. •This method is green chemistry method.

As the 'lungs of the city' and a refuge from pollutants, urban parks improve air quality by reducing ambient PM₁₀ through deposition and dispersion, particularly in major metropolises. This study evaluates the average relative reduction effect of urban parks on ambient PM10at the respiratory level (1.5 -2 m above ground) through deposition and dispersion, focusing on two widely planted tree species across the Middle East—oriental plane (Platanus orientalis L.) and white mulberry (Morus alba L.)—. These species are commonly used in urban green spaces due to their adaptability, broad canopy, and ability to withstand urban stressors. The research was conducted in Laleh Park, located in the heart of Tehran, one of the most polluted cities in the world. We developed a combined procedure integrating theoretical model (i.e., dry deposition flux) with both direct and indirect measurements of ambient PM10. We applied a dry deposition flux model using locally derived, seasonally adjusted deposition velocities for PM10 and PM2.5 on tree leaves, estimated through indirect measurements. Then, direct measurements taken inside and outside Laleh Park were used to disaggregate the park's effectiveness on ambient PM₁₀ into deposition and dispersion effects. The theoretical model showed that the park's trees contributed to a 10% total reduction in ambient PM10 at the respiratory level through deposition over the course of a year, with oriental plane trees accounting for a 9.3% reduction and white mulberry trees contributing an additional 0.7%. Direct measurements confirmed this finding, showing that the park's trees contributed to an average 10.4% reduction in ambient PM10 at the respiratory level through deposition over year. Furthermore, the dispersion of PM10 within the park accounted for an average 6.1% reduction in ambient PM10. Altogether, the combined effect of deposition and dispersion led to an average 16.5% reduction in ambient PM10 at the respiratory level inside the park. Elemental analysis of foliar deposits revealed elevated concentrations of Al and Pb, with enrichment factors of 110 and 7, respectively. The extremely high enrichment of Al and significant enrichment of Pb indicate strong anthropogenic contributions, likely from traffic-related sources. These findings highlight the potential for urban parks in cities like Tehran, to improve air quality, with implications for more effective urban planning. Further research is needed to assess the broader effectiveness of various types of urban green spaces (e.g., urban forests, parks, community gardens, and greenways) and plant species in mitigating different types of pollutants.

Whether the decadal accumulation of strain across active faults is representative of the long‐term rate of fault slip is a central and unresolved issue within active tectonics and earthquake science and is an issue of societal as well as academic interest. Significant variability in slip rate is often reported, and there is remaining uncertainty in the transferability between the two timescales of measurement. In this study, we examine the active fault systems across Iran, a region that is deforming due to the ongoing continental collision between Arabia and Eurasia. We compile all existing geological slip rates on strike‐slip faults within the region and compile/determine geodetic rates across the faults from GNSS networks and, in a few cases, from InSAR‐derived velocity fields. When the data set is taken as a whole we find agreement between the geological and decadal measurements, showing no resolvable differences in rate as averaged over decadal, Holocene (10 ka), and late Pleistocene (10–100 ka) time periods, with outliers from this trend likely resulting either from methodological limitations in individual studies or from assumptions of the age of offset landform features, which tend to underestimate the fault rate. Our study confirms that decadal measurements of strain accumulation are representative of long‐term accumulation of fault slip, at least within the uncertainties of our measurements in the Iranian plateau.

Since the early Neolithic (∼10,000 years ago), the Iranian Plateau has witnessed the development of sedentary human settlement facilitated by periods of favorable climatic conditions prompting gradual or sweeping changes. Climate factors significantly drove the hydroclimatic conditions in western and southeastern Iran, which varied in response to the Mid-Latitude Westerlies (MLW) and Indian Summer Monsoon (ISM). In addition, the input of dust and its eastward transport from the Arabian Peninsula and North Africa coincided with the North Atlantic cooling events. Peak wet conditions during the early Holocene in southeastern (c. 11.4–9.6 ka BP) and western Iran (c. 10.2–8.6 ka BP) indicate different timings in regional precipitation. The northward displacement of the Intertropical Convergence Zone at the beginning of the early Holocene caused the ISM to expand over southeastern Iran. At the same time, it strengthened the sub-tropical high-pressure and northward expansion over western Iran, resulting in dry conditions. Between 7.8 and 6.3 ka BP, gradual weakening and southward movement of the ISM and the decrease in intensity of the subtropical high-pressure systems over the Zagros region resulted in southeastern Iran becoming mild and the western region humid. Between 6.3 and 5.0 ka BP, a decrease in solar insolation ushered dusty and arid conditions on the Iranian plateau. Notably, human activities in the region started experiencing significant changes around the mid-Holocene. A concurrence exists during the wet (c. 5.0–4.5 ka BP) and dry (c. 4.2–3.2 ka BP) periods, coinciding with the rise and decline of multiple Bronze Age settlements. These settlements flourished in exchange and trade, pyro-technologies, and agro-pastoral production, demonstrating an increasing complexity in social organization and vulnerability to climate change. After transitioning into the Iron Age, southeastern Iran experienced relatively wet conditions c. 2.9 to 2.3 ka BP and 1.6 to 1.3 ka BP coincided with major territorial expansions and advancements under the Achaemenid and Sassanian dynasties. Merging the historical and archaeological data with palaeoenvironmental conditions indicates a concurrence of unfolding climatic and cultural changes, suggesting cascading effects that led to growth or settlement decline and abandonment.

Mineral prospectivity mapping (MPM) through the identification of prospective areas, by analyzing various exploration data and integrating them, plays a crucial role in reducing risk and improving decision-making in mineral exploration. However, this process is complex and faces many challenges due to the uncertainties inherent in the data and the various models used. In this study, our aim is to integrate several advanced methods to identify anomalies and use a new method to evaluate the performance of the developed models. To this end, five deep learning algorithms were employed for MPM, and their results were combined using a new method based on Bayesian statistics. This method was applied to five different models, resulting in a final composite model with a high level of confidence. The evaluation of results was performed using the Prediction Area plot (P-A plot). The final model demonstrated 6% higher accuracy compared to individual models and identified a smaller area as high-potential regions. Geologically, the results of the final model showed good alignment with microgranite, granodiorite to diorite, quartz diorite, and quartz monzodiorite units, indicating the success of this method in forward-looking modeling. The findings of this research suggest that combining models using this index can help reduce uncertainty and improve predictions in the identification of exploration targets, leading to more accurate decision-making and reduced exploration risks. This approach can be effectively applied in future exploration efforts.

Magnetic biochar composites were created by pyrolyzing siderite and sawdust in nitrogen gas (N2). adsorption was done in a variety of pH and temperature ranges on magnetic biochar. A magnet was used to extract the MB-liquid from each other following 24-hour shaking period. At Iran’s Geological Survey, Pb(II) concentration was measured using an ICP (Inductively Coupled Plasma). The adsorption-desorption process was carried out five times in order to evaluate the magnetic biochar’s reusability. The Pyrolysis of siderite in order to gain the MB changes its chemical composition and turns into a mixture of hematite, magnetite and maghemite, which imparts magnetism to the biochar and enriches its surface functional groups. The characterizations showed a higher specific surface area and porous structures in the magnetic biochar. An external magnetic field (magnet) was used to easily separate the magnetic biochar suspension because XRD investigation revealed that the primary component of the siderite magnetic biochar absorbent is magnetite, a ferrimagnetic mineral with substantial magnetic characteristics. The magnetic biochar composites’ strong adsorption capabilities toward Pb (II) ions were demonstrated by the batch adsorption tests. At pH 5.0 and T = 45 °C, Pb had its highest adsorption capability on magnetic biochar 96.92%. The mesoporous structure of magnetic biochar was indicated by the type IV isotherm. It has been demonstrated that adsorption most closely matches Langmuir’s model. Therefore, it can be said that monolayer adsorption has occurred. Biochar’s active sites were probably responsible for the fast adsorption process. Kinetics of lead adsorption with MB have been harmonized with pseudo-second order, indicating that the predominant mechanism for Pb adsorption onto magnetic biochar is chemisorption/surface complexation. In summary, magnetic biochar serves as a dual-functional material, adsorbing Pb(II) species and reducing them to less harmful forms, with the added advantage of easy recovery and reuse due to its magnetic properties. This makes it a promising material for the remediation of lead-contaminated environments.

Determining the timing of the initial continental collision is a fundamental step in accurately reconstructing the paleogeodynamic evolution of orogenic belts. This process necessitates a comprehensive integration of evidence gathered through various analytical techniques, both in the field and in the laboratory, to achieve a conclusive understanding. We here use comprehensive methods, including sandstone petrography, U-Pb dating, trace element and Hf isotopic compositions of the detrital zircon, in the Haji Abad (eastern Zagros Orogen) and the Shamil areas (west of the Minab-Zendan Fault) to constrain the timing of the initial collision between Arabia and Eurasia. Zircon U-Pb dating in the Haji Abad area reveals that detritus predominantly originates from the Arabia Pan-African basement (∼640 − 539 Ma, ƐHf (t): -10 to + 10) at the base of the Upper Oligocene-Lower Miocene Razak Formation. This is subsequently replaced up-section by detritus from Cenozoic and Mesozoic Eurasia magmatic-arc sources (~ 54 − 10 Ma, ƐHf (t): -2 to + 16; ~110 − 89 Ma, ƐHf (t): -2 to + 20, and ~ 175 − 163 Ma, ƐHf (t): -4 to + 10). In contrast, the Shamil area shows that detritus from the Pan-African Arabia basement remained dominant until the Early Miocene. The minimum age of continental collision is characterized by a significant change in provenance, transitioning from detritus sourced from the Arabia lower plate to that derived from the Eurasia upper plate. This transition is documented from the Late Oligocene in the Neyriz and Haji Abad areas along the Main Zagros Thrust, to the Middle Miocene (Langhian) in the Shamil area along the Minab-Zendan Fault.

The hypersaline Urmia Lake in NW Iran offers unique sedimentary environments sensitive to climate and environmental shifts, fostering coated grain formation and serving as a vital indicator of paleoenvironmental conditions. This study characterizes coated grains within a 25‐m sediment core dating back to ~50 cal ka bp , assessing their significance through morphology, internal structures, mineralogy, and geochemistry. Coated grains in Urmia Lake exhibit concentric laminations, primarily calcite and aragonite, revealing alternating light carbonate‐rich and dark organic‐rich laminations. These reflect seasonal and long‐term variations in water chemistry and biogenic production. Dry season algal blooms contribute to lamination, highlighting the interplay between seasonal climate fluctuations and the consequent lake water enrichment in calcium, carbonate, and bicarbonate ions. The diversity and abundance of coated grains indicate three main lake level fluctuation stages in the last ~50 cal ka: a lowering stage with dominant coated grains, a low lake level with dominant terrigenous fragments and minerals, and a high lake level with prominent Artemia urmiana fecal pellets. The role of the brine shrimp A. urmiana in coated grain formation involves absorbing calcium, carbonate, and bicarbonate ions and inhibiting coated grain formation during high lake levels while providing nuclei during lake lowering. An in‐depth investigation of coated grains provides a chemical and biological formation framework, highlighting three main episodes in the lake's history.

The Piranshahr pull-apart basin, situated in the northwestern part of the Zagros Main Recent Fault (MRF), is characterized by two right-stepping segments of the dextral MRF. Here, a combination of finite element modeling techniques, especially two-dimensional numerical modeling using ABAQUS software, along with field-based structural geological methods are used to assess the geometry and evolution of the pull-apart along the releasing stepovers in this strike-slip system. The utilized numerical approach applies two-dimensional (2D) finite-element modeling related to elastic Newtonian rheology to evaluate the distribution of stress and localization of strain within the pull-apart basin. This study provides valuable insights into the factors controlling the shape, as well as exploring the interaction between the pre-existing structures in this right-lateral strike-slip releasing stepover, pull-apart basin development in strike-slip systems, and stress-strain behavior by studying the impact of boundary conditions and fault overlap on the deformation pattern. The models consider three representative geometries of fault segment interactions, including underlapping, neutral, and overlapping stepovers, positioned at angles of 30°, 45°, and 60°. The results indicate that increased overlap creates an extensive and elongated deformation pattern, while decrease overlap leads to block rotation and a narrow deformation pattern. In addition, the degree of overlapping between parallel strike-slip faults influences the stress and strain. The mean normal stress within the transtensional basin, located between the fault segments, exhibits an extensional nature, while the region outside the stepover experiences general compressive mean normal stresses. The Piranshahr transtensional pull-apart basin exemplifies the progressive evolution of underlapping stepovers, resulting in displaying an elongated rhomboidal to trapezoidal-shaped geometry over time.

We compared the projected results of future hydrological changes (from 2040 to 2050) based on a 30-year weather dataset (1984–2014) in 7 rain gauges in the Jazmurian watershed with paleoclimatic changes inferred from established proxies in the region. By drawing parallels between anticipated future changes and past climatic conditions, we aim to develop a general understanding of how climate change may alter precipitation patterns in the watershed. The region is influenced by the Indian Ocean Summer Monsoon (IOSM) as well as the Mid-Latitude Westerlies (MLW). Precipitation projections for the future are derived using statistical downscaling outputs from IPCC Sixth Report models (CMIP6) under various Shared Socioeconomic Pathway (SSP) scenarios. In the western watershed, the CanESM5 model forecasts a decrease in MLW precipitation (32–20%) and an increase in IOSM precipitation (157–253%), leading to an overall rise of 0–28%. Conversely, the eastern section shows variable MLW precipitation changes (– 19% to + 20%) and a projected increase in IOSM precipitation (21–405%), resulting in a 9–120% rise. In the western region, the MPI-ESM1-2-HR model predicts a decline in MLW precipitation (30–3%) and an increase in IOSM precipitation (142–189%), with an overall rise of 9–22%. In the east, there is a decrease in MLW precipitation (23–9%) and an increase in IOSM precipitation (252–437%), leading to a rise of 44–91%. Future precipitation in the Jazmurian watershed is projected to increase despite potential decreases in MLW precipitation. Results suggest increases in the present low IOSM precipitation, leading to overall precipitation rises by 2050 compared to the historical levels. These findings highlight a trend towards wetter conditions, with the SSP 370 scenario showing the most significant rise in IOSM precipitation. The decrease in Mediterranean precipitation is consistent with findings from other GCMs and aligns with historical climate variations observed during previous warm and humid phases in the region. Nevertheless, given the strong correlation between the rise in the Earth's radiation budget and increased monsoon rainfall in the Jazmurian watershed since the late Pleistocene, we anticipate a significant rise in IOSM activity.

The Lower Red Formation (LRF) in Central Iran consists of the alternation of red-brown terrigenous sediments, marls and evaporites with basalt intercalations, exposed under the Chattian-Burdigalian Qom Formation and deposited on Eocene volcaniclastic sediments. The LRF is considered Rupelian in age. In the Deh Nar area, between Qom and Kashan cities, the LRF includes a basal conglomerate, alternations of brown-red sandstone and shale, colored marls with evaporite diapirs and top eroded red sandstone, with dark gray and green basalt lava intercalations. These sedimentary rocks are deposited in fluvial and playa environments, influenced by volcanic activities. Lower sandstone layers of the LRF in Deh Nar contain numerous vertebrate footprints, mostly preserved as convex hyporeliefs. Bird footprints are identified as Ardeipeda egretta, Aviadactyla vialovi, Avipeda phoenix and Gruipeda dominguensis. Small bird footprints are attributed to small, incumbent anisodactyl shoreline birds, such as sandpipers, and the larger of them to Gruiformes and Ciconiiformes, such as Ardeidae and Ciconiidae. Mammal footprints include Dehnaripus incognitusign. nov. and isp. nov., Lophiopus isp., Moropopus elongatus, Moropopus kashanensisisp. nov., Platykopus stuartjohnstoni, and Zanclonychopus isp. Dehnaripus incognitus is large circular manus and pes imprints; usually, they show unorganized, large, radial surface wrinkles and their digital or metatarsal/ metacarpal imprints are ambiguous. Moropopus kashanensis is tridactyl mammal pes and manus imprints and is distinguished by sharp, claw-like imprints in lateral digits of the manus from Moropopus elongatus. Most probably, the mammal tridactyl footprints of Deh Nar made by three toed, medium- to large sized terrestrial herbivores perissodactyls such as Tapiroidea. Platykopus and Zanclonychopus, however, were remained by large carnivores such as Amphicyonidae or Ursidae. Trackmakers of footprints in the LRF of Deh Nar area lived under hot and dry conditions of terrestrial and evaporitic environments, after cool and dry conditions of the Early Oligocene.

Through the examination of calcite twins, this research outlines the tectonic development and paleo stress patterns of the Paleozoic Routshon complex situated in the southeastern segment of the Sanandaj–Sirjan zone, a hinterland region of the Zagros orogeny in southeastern Iran. The study of orogenic phase indicates that the deformation event affecting the southern sector of the Sanandaj-Sirjan zone aligns with the Cimmerian orogenic phase of the Late Triassic period. A variety of structural features at both map and outcrop scales highlight the importance of slip partitioning in the structural evolution of this region, driven by inclined transpression. Observations suggest that the deformation related to contractional components includes steeply to moderately plunging folds, dip-slip domain deformation primarily involving thrusts, and ongoing deformation by strike-slip component motion, which results in thrust-related ductile shear zones. The analysis of calcite c-axis fabrics from mylonite samples obtained from these shear zones indicates a low-temperature monoclinic pattern of non-coaxial deformation. This deformation type underscores the impact of the strike-slip component in the development of progressive simple shear within thrust-related shear zones in this segment of the Sanandaj-Sirjan zone. Dynamic analysis of c-axis fabric data reveals a NE-SW orientation for the principal compressive axes (σ1) in this area. This direction, corroborated by additional data such as fault surface, GPS, and earthquake focal mechanism data, confirms that the orientation of the compressive axes (σ1) has remained consistent from the Late Triassic to the present.

The aim of this study was an integrative assessment of heavy metals associated with urban dust data in Iran (Ahvaz, Isfahan, and Shiraz). Samples of urban dust from four sites (traffic, industrial, residential, and Greenland) were collected, and ten heavy metal concentrations were determined using ICP_MS in each sample. The highest average concentrations of metals were at the traffic site for the Mn, Zn, and Cr metals. The PMF model indicates a higher percentage of Pb participation, which shows the importance of traffic resources. The highest non-carcinogenic risk (HI) was for the Cr and the carcinogenic risk was tolerable. To evaluate aerosol and its effects on urban dust, Aerosol Optical Depth (AOD) data were used during 2003–2023. According to the Mankendall test, the trend of AOD has been increasing in Esfahan (p_value < 0.05) and Shiraz. Although Ahvaz’s AOD is about two times greater than other cities, the aerosol trend in Ahvaz is decreasing.

The pressing concerns associated with climate change underscore the critical need for environmental conservation and sustainable resource management. As technological and industrial advancements continue to drive an escalating demand for materials, the extraction of which often involves mining, the imperative to explore novel methodologies for assessing and mitigating the environmental impact of such operations becomes evident. This study proposes a novel approach utilizing fuzzy logic to calculate the Forest Health Index (FHI), introducing both a Fuzzy Constructive FHI and a Fuzzy Destructive FHI index, each ranging from 0 to 100. The disparity between these indices, ranging from − 100 to 100, elucidates the overall forest health index. The study employs the Sungun copper mine as a case study, situated within the Arasbaran environmental protected area, which necessitates the application of forest-smart mining regulations and policies. To examine the impact of mining operations on forest health, remote sensing is employed to identify potential porphyry copper mineralization areas and to visualize deforestation trends at the Sungun copper mine from 2008 to 2023. Vegetation indices are utilized to estimate the Forest Health Index (FHI) through remote sensing methodologies, incorporating a combination of expert opinions and guest numbers to assess variables influencing the FHI (Forest Health Index). Results indicate that the Forest Health Index (FFHI) for Sungun is 2.1 (interpreting as rather low constructive fuzzy forest health index). For broader case studies, maximum and minimum FFHIs (Fuzzy Forest Health Index) were observed in Merian (37.92 interpreting as rather average constructive fuzzy forest health index) and Nimba Range Mineral Province (NRMP) (-25.7 interpreting as rather low/average destructive fuzzy forest health index), respectively. The outcomes emphasize the importance of implementing forest-smart mining practices to mitigate the adverse effects of mining activities on the Arasbaran forest and promote conditions conducive to forest health. It is better to diminish high road density, forest fragmentation and total deforestation along with improve forest core, forest connectivity and secondary forestry.

The Neotethyan Sanandaj–Sirjan Zone of western Iran has recorded major magmatic activities due to its continental arc tectonic setting during the Mesozoic. The Varcheh mafic intrusions were less‐studied plutons in the northern Sanandaj–Sirjan Zone (SSZ). Field evidence, petrography, geochemistry and U–Pb geochronological data were used to determine petrographic composition, geochemical nature, crystallization age and also to suggest a conceptual tectonomagmatic model for their emplacement. Small plutonic bodies are dominantly composed of monzogabbro that have intruded into the Cretaceous sedimentary rocks. Based on U–Pb zircon datings, these rocks have crystallized at 125–118 Ma in late Early Cretaceous (Barremian–Aptian), and are older than the supposed ages reported on geological maps. Varcheh rocks are not just typical calc‐alkaline rocks and some show alkaline affinity. Negative anomalies in Nb–Ta–Ti and enrichments in some large‐ion lithophile elements on spider diagrams are consistent with a subduction‐zone setting. Potential deep source for magma generation is partial melting of subcontinental lithospheric mantle wedge above a subducting slab of oceanic lithosphere. The spaces for the Varcheh mafic intrusions are accommodated by dominant dextral strike‐slip movement in a continental arc experiencing extension during late Early Cretaceous subduction. According to the zircon U–Pb geochronology results in this paper and previous U–Pb ages in the northern part of the SSZ, the mid‐Cretaceous magmatism reveals a significant NW‐ward younging trend and migration of the magmatic arc from the Barremian–Aptian in south‐east to the Albian–Cenomanian in the north‐west.

Zabol City in eastern Iran has been recognized as one of the windiest, dustiest, and most unhealthy urban environments globally. This work examines the chemical speciation, environmental contamination, and human health risk associated with atmospheric dust in Zabol and surrounding areas, via analysis of 77 dust samples collected at 12 urban and rural sites from October 2018 to September 2020. On average, the concentrations of trace elements followed a decreasing order of Mn > Ba > Sr > Zn > Cr > V > Ni > Cu > Pb > Co > As > Mo > Cd, while abundant elements Al and Fe accounted for 5% and 2.9% of airborne dust, respectively. Significant enrichment factors were found for As and Cd and moderate for Mo. The ecological risk index indicated moderate pollution, with the highest contributions from Cd (68%) and As (25%). The intensive use of As-based fertilizers and pesticides in the agricultural lands in the Sitan Basin is the most likely source for the high As levels, while Cd, Pb, and Mo in airborne dust can be partly attributed to traffic-related contamination. Non-carcinogenic risk assessment revealed that ingestion is the primary exposure source of potentially toxic elements (PTEs) for both children and adults, with deleterious health effects, followed by skin contact and inhalation. The Hazard index (HI) for selected PTEs decreased in the order of Cr > As > Pb > Ni > Cd > Cu > Zn for both children and adults, classified within safe limits (HI < 1). However, Cr and As posed cancer risks above the safety threshold (> 10− 4) through ingestion exposure. Current results indicate that Zabol is still experiencing significant environmental and ecological contamination, as well as important health risks due to dust contaminated PTEs, necessitating appropriate mitigation strategies.

Geodynamic models implying subduction of continental crust either consider this process happening during collision, when the continental margin of the lower plate attempts subduction, or in pre-collisional stages, when tectonic erosion of the upper plate or subduction of continental extensional allochthons drag continental crust in the subduction channel. In the Zagros orogen (W Iran), high-pressure rocks are known only from the Sanandaj-Sirjan Zone, NE of the Main Zagros Thrust. Here, eclogites of the North Shahrekord Metamorphic Complex suggest subduction of continental crust slices derived from the upper plate (Central Iran) during the onset of the Neo-Tethys subduction along the southern margin of Iran. Eclogites record a clockwise pressure-temperature-time path, with pre-eclogitic epidote-amphibolites-facies phase assemblages preserved in garnet cores, a high-pressure stage, and a subsequent retrogression at amphibolite-facies conditions. By means of forward thermodynamic modelling and ⁴⁰Ar/³⁹Ar geochronology, the peak metamorphism has been constrained at 1.9-2.1 GPa and 550-600 °C, in the 191-194 Ma time span. The following retrogression during exhumation lasted at least until 144 Ma. Our data suggest that the onset of the Neo-Tethys subduction traces back prior to 190 Ma, involving together with the Neo-Tethys oceanic lithosphere also slices of the upper plate continental crust scraped off by means of tectonic erosion processes.

Many types of biochars are being used as an adsorbent to remove multiple contaminants, including heavy metals, nutrients and organic compounds from environments. Magnetic biochar composites have been widely used to maximize biochar recycling from aqueous solutions. Magnetic biochar composites were created by pyrolyzing siderite and sawdust in nitrogen gas (N2). adsorption was done in a variety of pH and temperature ranges on magnetic biochar. A magnet was used to extract the MB-liquid from each other following 24-hour shaking period. At Iran's Geological Survey, Pb(II) concentration was measured using an ICP (Inductively Coupled Plasma). The adsorption-desorption process was carried out five times in order to evaluate the magnetic biochar's reusability. The characterizations showed a higher specific surface area and porous structures in the magnetic biochar. An external magnetic field (magnet) was used to easily separate the magnetic biochar suspension because XRD investigation revealed that the primary component of the siderite magnetic biochar absorbent is magnetite, a ferrimagnetic mineral with substantial magnetic characteristics. The magnetic biochar composites' strong adsorption capabilities toward Pb (II) ions were demonstrated by the batch adsorption tests. At pH 5.0 and T = 45°C, Pb had its highest adsorption capability on magnetic biochar. The mesoporous structure of magnetic biochar was indicated by the type IV isotherm. It has been demonstrated that adsorption most closely matches Langmuir's model. Therefore, it can be said that monolayer adsorption has occurred. Biochar's active sites were probably responsible for the fast adsorption process. Kinetics of lead adsorption with MB have been harmonized with pseudo-second order, indicating that the predominant mechanism for Pb adsorption onto magnetic biochar is chemisorption/surface complexation. For Pb(II) environmental remediation, MB adsorbent is suggested to be employed because of its straightforward synthesis process, inexpensive cost, ease of separation, good efficiency and environmental friendliness.

The pressing concerns associated with climate change underscore the critical need for environmental conservation and sustainable resource management. As technological and industrial advancements continue to drive an escalating demand for materials, the extraction of which often involves mining, the imperative to explore novel methodologies for assessing and mitigating the environmental impact of such operations becomes evident. This study proposes a novel approach utilizing fuzzy logic to calculate the Forest Health Index (FHI), introducing both a Fuzzy Constructive FHI and a Fuzzy Destructive FHI index, each ranging from 0 to 100. The disparity between these indices, ranging from − 100 to 100, elucidates the overall forest health index. The study employs the Sungun copper mine as a case study, situated within the Arasbaran environmental protected area, which necessitates the application of forest-smart mining regulations and policies. To examine the impact of mining operations on forest health, remote sensing is employed to identify potential porphyry copper mineralization areas and to visualize deforestation trends at the Sungun copper mine from 2008 to 2023. Vegetation indices are utilized to estimate the Forest Health Index (FHI) through remote sensing methodologies, incorporating a combination of expert opinions and guest numbers to assess variables influencing the FHI. Results indicate that the Forest Health Index (FFHI) for Sungun is 2.1, with maximum and minimum FFHIs observed in Merian (37.92) and Nimba Range Mineral Province (NRMP) (-25.7), respectively. The outcomes emphasize the importance of implementing forest-smart mining practices to mitigate the adverse effects of mining activities on the Arasbaran forest and promote conditions conducive to forest health.

We present a detailed description of the Middle Miocene (Chokrakian and Karaganian) depositional environments of the Eastern Paratethys Sea in the southern Caspian Basin. The Chokrakian comprises a 500-m-thick succession of marls and sandstones, termed herein Javarem Formation, which formed in coastal marine environments. The lower Javarem Fm. developed in calm lagoonal settings, indicating frequent exposure under a predominantly dry climate and occasional formation of evaporites. The upper part of the Javarem Fm. Is characterized by mixed siliciclastic-carbonatic sediments with ooids of agitated, warm, hypersaline tidal shoals. Above follows the about 500-m-thick Vashi Formation, which is correlated with the Karaganian regional stage. The formation is characterized by an alternation of reddish marls with thick sandstones and gravel beds with terrestrial gastropods, ubiquitous pedogenetic features and occasional root horizons. The depositional environment is interpreted as a floodplain with gravelly channels of an arid to semiarid climate. The successions of the Javarem and Vashi formations capture the transition from the shallow marine Iranian shelf into the northern Iranian coastal plain around 13.8 Ma, following the onset of the Miocene Climate Transition and the coinciding global sea level drop around the Langhian/Serravallian boundary.