Geosystems and Geoenvironment最新文献

{"title":"Exploration of iron ore deposits in parts of Kogi State, northcentral Nigeria: Analyses from airborne magnetic and ASTER datasets","authors":"Ayokunle Adewale Akinlalu","doi":"10.1016/j.geogeo.2025.100359","DOIUrl":"10.1016/j.geogeo.2025.100359","url":null,"abstract":"<div><div>Kogi State is known for its iron ore deposits, and Kakanda township is one of those places that possess iron ore deposits. However, little information about the extent and locations of possible iron ore mineralized zones is available due to limited research in that area. Hence, this study utilized aeromagnetic and Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) datasets for the delineation of ironstone and banded iron deposits comprising magnetite and hematite in Kakanda and its environs in Kogi State, northcentral Nigeria. Enhancement techniques such as residual magnetic amplitude and analytic signal amplitude carried out on the aeromagnetic data revealed the concentration of iron ore deposits, especially in the southern, eastern and western parts of the study area. This finding is consistent with signatures derived from other data enhancement techniques involving the total horizontal derivative, tilt derivative and 3D Euler deconvolution techniques, which are principally used to map structures guiding mineralization in the study area. Furthermore, analyses of the ASTER dataset using true and false color composites and combinations of band ratios indicate the occurrence of iron oxide and clay alterations related to iron ore mineralization in the study area. The signatures related to iron ore mineralization in the aeromagnetic data and ASTER dataset are consistent with each other. The overlap of these signatures was used to produce the iron ore prospectivity map of the study area. The study showed that areas of delineated lineament coincide with areas of iron ore mineralization. In the same vein, areas of dense lineaments coincide with areas of iron ore mineralization, especially in the southern and eastern parts of the study area. Therefore, the mineralization in the study area is structurally controlled. The iron ore prospectivity map produced will serve as reference for mineral explorationists in the area to engage in targeted exploration, rather than random exploration and exploitation especially in developing countries which impacts the environment negatively. Hence, further exploration activities involving electrical resistivity and gravity surveys and geochemical studies should focus on areas where there is an evident overlap of lineament and signatures reflecting iron ore mineralization in the study area.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100359"},"PeriodicalIF":0.0,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-K, I-type Tonian post-collisional magmatism in the South Delhi Terrane, NW India: Petrogenetic and tectonic implications","authors":"Manisha,&nbsp;Parampreet Kaur,&nbsp;Naveen Chaudhri","doi":"10.1016/j.geogeo.2025.100360","DOIUrl":"10.1016/j.geogeo.2025.100360","url":null,"abstract":"<div><div>The limited whole-rock geochemical data of the granitoids exposed in the southern domain of the South Delhi Terrane, Aravalli orogen, northwestern India characterised these rocks as subduction-related continental arc I-type granites. The new comprehensive mineralogical and geochemical data of these Tonian (975–965 Ma) granitoids, particularly those exposed around the Bekariya region, reveal that they are not continental arc I-type granites. These granitoids are rather high-K, I-type, weakly peraluminous to metaluminous, magnesian to ferroan, calc-alkalic to calcic and emplaced in a post-collisional extension regime. They comprise predominantly high-temperature (764–845°C) granitoids, along with a subordinate volume of low-temperature (669–776°C) granitoids. The nearly flat to variably inclined [(Gd/Yb)_N = 1.0–4.8)] and depleted [(Gd/Yb)_N = 2.8–3.0)] HREE patterns of the granitoids with notable negative (Eu/Eu* = 0.21–0.71) and insignificant (Eu/Eu* = 0.83–0.85) Eu anomalies, respectively and variable Sr/Y ratios (0.6–93.9), imply variation in the depth of their magma generation. Taken together, these data suggest that the high-temperature I-type Bekariya granitoids most likely originated from dehydration partial melting of metabasaltic-metandesitic crust that required a significant influx of heat in a post-collisional or post-orogenic setting. In contrast, the minor low-temperature I-type granitoids probably resulted from partial melting of a similar source by the infiltration of a water-rich fluid phase in a subduction-related setting. Furthermore, the study signifies that I-type granitoids are more voluminous than A-type granitoids in the South Delhi Terrane and were emplaced coevally in a post-collisional extension regime during the Tonian period.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100360"},"PeriodicalIF":0.0,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Innovative airborne geophysical strategies to assist the exploration of critical metal systems","authors":"Karl Kwan ,&nbsp;Stephen Reford","doi":"10.1016/j.geogeo.2024.100344","DOIUrl":"10.1016/j.geogeo.2024.100344","url":null,"abstract":"<div><div>Critical metals are essential in sustaining the high technology and the green energy transition of modern societies. The future discovery of new critical metal deposits will likely be made at increasing depths and under thick cover sequences. The key roles of the four airborne geophysical exploration methods, gravity, magnetometry, electromagnetism and gamma-ray spectrometry, are reviewed in this article. The measured data from airborne magnetic, gravity and electromagnetic surveys can be inverted to reveal the distribution of underlying mineral prospects in terms of magnetic susceptibility, density and electrical resistivity/conductivity beneath the surface.</div><div>The interpretation of geophysical data is important in relating geophysical responses to the lithology and geophysical anomalies to potential exploration targets that are concealed under cover. Gamma-ray spectrometry can identify near-surface hydrothermal alteration zones and uranium systems. Structural complexity maps can provide additional key parameters for the exploration targeting of structurally controlled critical metal systems. We briefly discuss the application of airborne geophysical methods to efficiently guide the exploration of concealed critical metal deposits. A robust understanding of the geological setting of the respective mineral prospect is the most relevant factor in choosing the most efficient geophysical exploration strategy. Geophysical tools will likely play an increasingly important role in guiding the future discovery of concealed critical mineral systems.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100344"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Critical metals exploration and energy transition – A perspective","authors":"Allan Trench,&nbsp;John Sykes","doi":"10.1016/j.geogeo.2025.100353","DOIUrl":"10.1016/j.geogeo.2025.100353","url":null,"abstract":"<div><div>The critical metals theme is well established, with long-run demand-side growth driven by cleaner energy and new technology applications. Delivering the energy transition comes with a parallel requirement to discover and then develop new sources of critical metals supply. Constraints on new supply start with the exploration process, where land access, and satisfying administrative, legislative and stakeholder requirements have become more challenging, uncertain, slower, and costly in recent years. The consequences of higher exploration access costs, and extended timelines, favour major mining companies over junior explorers, where the majors have sustainable cash flows. Greater uncertainties in land access globally favours established mining jurisdictions with a track record of resolving competing land use issues, over and above more frontier jurisdictions that lack both a track record and streamlined processes to facilitate multiple new resource developments.</div><div>Technical constraints to discover and develop adequate new sources of supply also vary between critical metals. Whilst accurate forecasts of the timing of new supply is difficult, including the identification of discovery and development constraints, and the relative resource depletion between markets, paradoxically, it is the newer, niche, critical metals markets that may prove less difficult to expand supply versus the larger critical metals markets. The reasons are twofold: Firstly, that absolute tonnage requirements for new critical metals supply are lower in the emerging markets (e.g., lithium, vanadium, niobium) than for larger markets (e.g., copper). As such, fewer new discoveries and mine developments are required to fulfill anticipated market growth requirements in the smaller critical metals markets. Secondly, that the exploration search-space within established mining jurisdictions for the emerging critical metals markets is immature, allowing for new Tier-1 discoveries to emerge early. In contrast, within the major critical metals markets such as copper, the exploration search-space in established mining jurisdictions is mature, resulting in lower exploration efficiency and fewer, deeper, new Tier-1 discoveries. The consequence is that discovery-led bottlenecks to future metals supply for the energy transition may be fewer in the niche critical metals markets than for mainstream metals markets, that also have new energy applications vital to the clean energy transition.</div><div>Given that the mining history and production of many critical metals is recent, the recycling of critical metals does not present a solution to satisfying new demand: exploration and discovery are pivotal. By discovering the critical metals for low-carbon and “renewable” energy technologies, mineral exploration has a key role to play in facilitating the green energy transition.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100353"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Litho-tectonostratigraphy of the Dhanjori Basin, India: A fold-thrust sequence and its tectonic relation with the Singhbhum Shear Zone","authors":"Saptarshi Mallick ,&nbsp;Arup Ratan Manna ,&nbsp;Arun Kumar Kujur ,&nbsp;J.P. Mohakul","doi":"10.1016/j.geogeo.2025.100351","DOIUrl":"10.1016/j.geogeo.2025.100351","url":null,"abstract":"<div><div>Based on direct field evidence, litho-tectonostratigraphy of the Neoarchaean-Palaeoproterozoic Dhanjori Basin, situated at the northeastern fringe of the Singhbhum Craton (SC), is being appraised for the first time. Entire sequence of the Dhanjori Basin is presently interpreted as a single-stack of volcano-sedimentary assemblage of terrestrial clastic metasedimentary rocks of conglomerate-quartzite-phyllite in the lower part followed by meta-volcanic-volcaniclastic sequence. Singhbhum Shear Zone (SSZ) marks the eastern boundary of the Dhanjori Basin with Singhbhum Group representing North Singhbhum Mobile Belt (NSMB). In the western and southern margin, the Dhanjori sequence exhibits angular unconformity with the Palaeoarchean Iron Ore Group (IOG) represented by the Badampahar-Gorumahisani Belt and nonconformity with the Singhbhum Granite Complex and Mayurbhanj Granite-Gabbro which also indicates its post Iron Ore Orogenic development along SC margin. The rocks of the Dhanjori Basin and NSMB have undergone the same progressive deformational event of the North Singhbhum Orogeny but the Dhanjori Basin escaped the initial phase of it. SSZ, developed during later phase of this progressive deformational event, affected both of these packages. Prior to this, the Dhanjori Basin was undeformed. Four splays of SSZ transects the Dhanjori Basin longitudinally. These splays are characterized by development of two sets of mylonitic fabrics with moderate to low east-northeasterly dip and downdip mineral stretching lineation. They have resulted in thrust related repetition of the Dhanjori sequence within interior part of the basin. The third set of planes having same trend as mylonitic fabric but dipping steeply in opposite direction, is present in the form of spaced cleavage, kinks and fractures. These planes are formed out of stress release after the episodes of shearing-mylonitisation-thrusting. Older quartzites are thrusted over younger metavolcanics in all along the eastern margin and central part. Isolated overthrusted units of NSMB also overlie the Dhanjori package as thrust klippe. Mafic-Ultramafic rocks with plutonic fabric, present in the southeastern and northern part of Dhanjori Basin, exhibits intrusive relation with the Dhanjori package.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100351"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The heterogeneous distribution of critical metal mineral resources: An impending geopolitical issue","authors":"David I. Groves ,&nbsp;D. Müller ,&nbsp;M. Santosh ,&nbsp;Cheng-Xue Yang","doi":"10.1016/j.geogeo.2024.100288","DOIUrl":"10.1016/j.geogeo.2024.100288","url":null,"abstract":"<div><div>Concerns that anthropologic carbon emissions will result in catastrophic climate change have resulted in Net Zero policies that have energized a clean energy transition in developed, particularly western, countries. This is resulting in attempts to produce so-called ‘renewable’ energy using critical metals that, unfortunately, are largely non-renewable. The critical metals that are essential to this clean energy transition occur in rare mineral deposits (0.02% of the Earth's land surface) that are ∼10 to &gt;10,000 times enriched in metals relative to their crustal abundance. The deposits are part of larger scale mineral systems that require a rare conjunction of parameters that involve natural recycling of metals through the crust and mantle via the Earth's unique subduction system during the tectonic evolution of the continents. As each continent had its own unique tectonic history, the global distribution of these rare metallic mineral deposits is very heterogeneous. A major issue for critical metal supply is represented by the evolution of BRICS as an economic group that comprises Brazil, Russia, India, China, and South Africa, all metal-endowed nations, with only metal-endowed Australia and Canada and a few lesser endowed countries firmly aligned with another group strategically allied with the USA. In stark contrast, a well-endowed China has abundant critical metal deposits and obtains trace critical metals through processing of metallurgical biproducts of base metal ores, leading to a growing domination of the clean energy industry. Critical metals, particularly Ga, Ge, and REEs, and graphite are already used in trade disputes among some countries and industrial weaponization using critical metals such as Ni on to global markets is already evident. From a geoscience viewpoint, in the short term, global exploration is needed to provide a more homogeneous distribution of critical metal deposits. However, exploration is hampered by increasing environmental, and human rights issues and sovereign risks that are becoming ever more challenging for most major mining and exploration companies in western countries. This requires that a global circular economy involving recycling is a priority.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100288"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141144228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of aerosols on atmospheric processes and climate variability: A synthesis of recent research findings","authors":"Steffi Joseph Perumpully ,&nbsp;Sneha Gautam","doi":"10.1016/j.geogeo.2024.100317","DOIUrl":"10.1016/j.geogeo.2024.100317","url":null,"abstract":"<div><div>Aerosols are minuscule particles suspended in the Earth's atmosphere that significantly impact air quality. Aerosol optical depth serves as a crucial metric for gauging aerosol optical properties and concentrations, thereby influencing the climate. Atmospheric processes, in conjunction with meteorological factors such as temperature and humidity, influence aerosol behavior, molding weather patterns and climate fluctuations. This research employs bibliometric analysis to pinpoint key research fields and clusters, which are subsequently followed by countries, authors, keywords, and journals contributing to aerosol studies. Leveraging the VOSviewer software, a scientometric approach is utilized to present an accurate portrayal and evolution within the realm of aerosols. The United States has been instrumental in this research domain based on the volume of articles published and citations. Key aerosol research areas from 2009 to 2024 include MODIS aerosol products, global climate modeling, and aerosol impacts and properties. This review aims to provide researchers with an overview of these primary research domains while highlighting the importance of understanding aerosol interactions for addressing climate change and protecting the environment and ecosystems through sustainable solutions.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100317"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nickel: A tale of two cities","authors":"Richard Schodde ,&nbsp;Pietro Guj","doi":"10.1016/j.geogeo.2025.100356","DOIUrl":"10.1016/j.geogeo.2025.100356","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Asides from subsea manganese nodules, there are essentially three main sources of nickel (Ni) supply: newly mined (1) magmatic Ni sulfide ore, (2) Ni laterites (limonitic and saprolitic) and (3) new and old End-of-life (EoL) recycled stainless steel scrap, mostly melted to produce stainless steel of similar grade. Traditionally Ni sulfide ore has been refined into high-purity, LME-deliverable, Class 1 products, such as Ni briquettes and powder for a range of specialised applications, besides stainless steel, including chemical EV battery precursors. By contrast, Ni laterites have been in the past the primary source of lower-purity, Class 2 products, such as ferronickel and nickel pig iron (NPI) as feed for stainless steel production. Processing of Ni laterites using high pressure acid leaching (HPAL) has generally proven to be technically complex and often the source of financial problems. This, however, has changed starting with a daring but successful gamble on the side of Ni-laterite-rich Indonesia that, in an endeavour to attract investment in downstream processing, in 2014 introduced a ban on the exportation of Ni ore, giving local miners 5 years to establish their processing facilities. Initially the Indonesian Ni industry languished, much to the benefit of Ni producers elsewhere, until China entered the scene financing downstream processing of Ni laterites at an unprecedented scale and more recently introducing innovative improvements to the HPAL process to a level that makes production of refined Ni products from laterites, not only possible, but competitive with traditional Ni sulfide sources. This has had a devastating effect on Ni sulfide mines, with many suspending and others reducing production. There is no doubt that economies of scale, metallurgical innovation, and massive, low-cost Chinese funding are behind this success, even though the Ni sulfide sector claims that central to it is a somewhat accommodating attitude on the side of the Indonesian environmental authorities. The attempt on the side of Ni sulfide miners to differentiate themselves as ‘clean’ Ni producers deserving a price premium did not get traction, but concerns regarding the environment, the impact on the affected communities, and the long-term sustainability of the lateritic Ni resources appear to be emerging as serious political issues in Indonesia. The paper analyses the size, composition, and geographical distribution of the current world Ni resources, their growth, and their capacity to satisfy the medium-term increase in demand due to the transition to clean energy despite diminishing exploration discoveries. It also speculates on how long the current laterite dominance of the Ni market may persist before the pendulum may swing back to Ni sulfides. Despite rising environmental pressure, there appears to be a reasonable chance that current and foreseeable Ni resources may prove adequate to satisfy rising demand in the short to medium term. By contra","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100356"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated geophysical and remote sensing/GIS interpretation for delineating the structural elements and groundwater aquifers of the Foumban locality, Western Highlands of Cameroon (WHC)","authors":"Z. Mfonka ,&nbsp;P.S. Kouassy Kaledje ,&nbsp;A. Anaba Onana ,&nbsp;D. Nsangou ,&nbsp;A. Kpoumie ,&nbsp;M. Zammouri ,&nbsp;P-D. Ndjigui ,&nbsp;J.R. Ndam Ngoupayou","doi":"10.1016/j.geogeo.2024.100343","DOIUrl":"10.1016/j.geogeo.2024.100343","url":null,"abstract":"<div><div>This study was conducted in the Foumban locality, in the Western Highlands of Cameroon (WHC) where a majority of the population is suffering from scarcity of water for domestic purposes and many other related uses. Thus, it aims at investigating the structural and geo-electrical characteristics of the aquifer system of the locality, based on an integrated approach (Geophysics and GIS). For this purpose, the Landsat 8 image with 30 × 30 m resolution and 20 vertical electrical sounding (VES) data were analysed with ArcGIS, ENVI version 5.3<strong>,</strong> Stereonet v9.3.2 and QWSELN software, coupled with the principal component analysis (PCA). Based on the structural aspect, a total of 224 fractures with lengths higher than 1 km have been identified and drawn. They are mainly grouped in the Centre, North-East and South-East of the study area. Five main families within linear directions have been identified: N10–20 (13.84%), N20–30 (17.86%), N50–60 (9.82%), N80–90 (5.90%) and N140–150 (7.59%). They are mostly oriented NE-SW, following the Cameroon Volcanic Line (CVL). These fractures which play an important role in the capacitive and drainage function of the fractured aquifer result from the tectonic movements and decompression of rock masses. According to the geoelectrical characteristics, different VES curve types have been identified, corresponding to various alternate layers of conductive, semi resistive and resistive formations; with thickness ranging between 0.41 to 47 m and resistivity values between 82 to 3410 Ωm. The three cross-section realised (A-A’, B-B’ and C-C’) show that those alternate materials (topsoil, laterite, weathered layer, fractured basement and fresh basement rock) are discontinuous both vertically and horizontally, highlighting the geometry and hydrogeological complexity of these areas. This study is a contribution to a better understanding of the basement aquifers milieu; it could be used by the water supply departments and decision makers for locating appropriate positions of new productive wells in the study area.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100343"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of vehicular emissions on ozone levels: A comprehensive study of nitric oxide and ozone interactions in urban areas","authors":"Amaury de Souza ,&nbsp;José Francisco de Oliveira-Júnior ,&nbsp;Kelvy Rosalvo Alencar Cardoso ,&nbsp;Sneha Gautam","doi":"10.1016/j.geogeo.2024.100348","DOIUrl":"10.1016/j.geogeo.2024.100348","url":null,"abstract":"<div><div>This study examines the relationship between nitric oxide (NO) concentrations and vehicular traffic, focusing on trucks and buses as key sources of NO emissions. The conversion of NO to nitrogen dioxide (NO₂) influences ozone (O₃) formation, with excess nitrogen oxides (NO_X) limiting O₃ production. Elevated O₃ levels under certain conditions pose public health risks. This study analyzes seasonal and diurnal variations in NO₂, NO_X and O₃ concentrations, accounting for meteorological factors and the impact of agricultural fires. Pearson correlation coefficients between pollutants and climatic variables were calculated, along with the ventilation coefficient (VC), to explore pollutant-atmosphere dynamics. Analysis of 2021 data revealed peak SO₂, NO, NO₂, NO_X and O₃ levels between August and October, with O₃ values averaging 18 ppb (1.90–79.70 ppb range). Seasonal trends showed NO_X peaks in autumn and winter, while O₃ concentrations were highest in summer and spring, driven by temperature and solar radiation. Negative correlations between SO₂, NO, NO₂, NO_X and O₃ were observed (e.g., <em>r</em> = -0.312, <em>p</em> &lt; 0.01). VC values increased from 1 p.m., peaking at 10 p.m. (2000–4500 m/s), and stabilized during early morning hours. The findings emphasize the need for integrated urban air quality management, combining vehicle emission controls and strategies to address meteorological influences and agricultural fires. Continuous monitoring and targeted policies during high-risk periods, particularly August to October, can mitigate pollutant impacts, improve air quality, and safeguard public health in urban areas.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100348"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}