Geosystems and Geoenvironment最新文献

{"title":"Reconstructing ancient vegetation, climate, depositional setting and ecology of the West Bokaro Coalfield, India: Insights from megafloristics and palynofacies","authors":"Soumyashree Nanda ,&nbsp;Shreerup Goswami ,&nbsp;Neha Aggarwal ,&nbsp;Debashish Das","doi":"10.1016/j.geogeo.2024.100334","DOIUrl":"10.1016/j.geogeo.2024.100334","url":null,"abstract":"<div><div>This study investigates the ancient vegetation, climate, depositional setting, and ecology of the West Bokaro Coalfield, with a focus on megafloral and palynofacies analyses from the Parej East Open Cast Project (OCP). The floral assemblage includes 23 taxa, notably 17 species of <em>Glossopteris</em>, along with <em>Noeggerathiopsis hislopii</em> and Equisetales. This research records two new species of <em>Glossopteris</em> (i.e., <em>Glossopteris lanceolatus</em> and <em>Glossopteris subtilis</em>) and a new record of <em>Noeggerathiopsis hislopii</em> from this coalfield. The palynofacies study, indicates a low-energy, distal depositional environment with flooded palaeomires during the late Artinskian age. The palaeofloral assemblage represents a systematic morphological evolution in a comparatively cooler climate with enough rainfall, calm wind conditions and moderate intensity of light throughout the lower Barakar sedimentation in the Parej East area of West Bokaro Coalfield. The presence of Karharbari flora indicates the survival of older floral elements during the early Barakar sedimentation. The findings provide new insights into the palaeoenvironment of this important Gondwana basin, enriching our understanding of the interplay between climate, vegetation, and depositional processes during the Permian.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100334"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131365","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":"Will future copper resources and supply be adequate to meet the net zero emission goal?","authors":"Pietro Guj ,&nbsp;Richard Schodde","doi":"10.1016/j.geogeo.2024.100320","DOIUrl":"10.1016/j.geogeo.2024.100320","url":null,"abstract":"<div><div>The fact that in recent times mineral exploration has been disappointing and that transition to clean energy to achieve net zero emission by 2050 will place extraordinary pressure on copper demand, are beyond dispute. The critical question is to what extent will copper supply be capable of satisfying growing demand in a net zero future. Reality is that global copper resources have been growing significantly and steadily for decades despite increasing mine production. Besides, with dwindling exploration discoveries, this increase is primarily attributable to expansion of the resources of existing deposits through a combination of better progressive delineation and re-assessment of classification of resources in response to economic and technological changes, the so-called Australasian Joint Ore Reserves Committee (JORC) ‘modifying factors’. Analysis of MinEx Consulting's global mineral deposit database indicates that just the resources of deposits discovered since 2010 have been growing at estimated Compound Annual Growth Rates (CAGRs) in the range 7.5% to 15.5%, but greater additional tonnage is associated with deposits discovered before 2010. The result is that tens of millions of tonnes of copper are added to the inventory each year, notwithstanding increasing production and mounting Environmental, Social and Governance (ESG) pressure sterilising some deposits. In essence, copper supply shortages are unlikely to result from depletion of copper resources but rather from possible inadequacy of mining and processing capacity. Geopolitical supply risk is also low compared to some other critical metals (e.g., Co and Ni) on account of the large number and geographical dispersion of copper deposits. Increases in price due to a perception of impending scarcity will ensure that future capacity will, at a minimum, continue to grow along its historical 3% CAGR. In addition, it will create strong incentives for above-trend capacity utilisation and improvement in recycling collection and recovery. This will be followed by acceleration of expansion of capacity at many existing mines, and development of deposits at the advanced feasibility stage, releasing copper to market at lower capital cost and on shorter timeframes than exploring for and developing new mines. Estimates of possible levels of above-trend increments in capacity for the various components of the current copper endowment show that, while shortages may occur, they will not be as serious as currently generally expected. This does not mean that net zero emission may not be delayed beyond 2050, but it is more likely that it may be delayed by a range of other constrains and impediments unrelated to availability of copper, and that such delays may give copper supply breathing time.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100320"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131629","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: Their mineral systems and exploration","authors":"Daniel Müller ,&nbsp;David I. Groves ,&nbsp;M. Santosh ,&nbsp;Cheng-Xue Yang","doi":"10.1016/j.geogeo.2024.100323","DOIUrl":"10.1016/j.geogeo.2024.100323","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Complex geological formation processes under a variety of tectonic regimes have led to a heterogeneous global distribution of the critical metal resources that will be increasingly in demand due to Net Zero and the clean energy transition. Although brownfield exploration around existing mines can add to inventories of some critical metals, including copper in the short to medium term, all mines have a finite life with many historical giants already exhausted. Therefore, without a revolution in metal recycling, successful global greenfield exploration is of key importance.&lt;/div&gt;&lt;div&gt;If greenfield exploration is to supply a significant proportion of critical metals to meet future supply for a sustainable economic future, it is imperative that superior conceptual models are employed for initial ground selection. This requires an understanding of the critical components of the wide variety of metallic mineral systems that contain these critical metals and their temporal distribution and tectonic settings. Greenfield exploration faces numerous challenges as new discoveries are commonly concealed by younger sedimentary cover and they occur in increasingly remote terrains and at greater depths, resulting in declining discovery rates despite rising budgets.&lt;/div&gt;&lt;div&gt;Some mineral systems have high preservation potential and are distributed within well-established temporal ranges in Earth history. These systems include orogenic gold, VMS-type Cu-Pb-Zn, intrusion-hosted Ni-Cu±PGE, carbonatite REE, and SEDEX, MVT, Broken Hill-type, and Zambian-type base-metal systems. Understanding the temporal range and tectonic setting of such critical mineral systems aids conceptual targeting to define new exploration spaces. However, many of the Precambrian critical mineral deposits within these systems are now situated in subdued topography and have experienced regolith development such that they have thick cover ranging from desert sands to thick complex regolith, to glacial till. All scenarios represent technical and financial challenges in terms of successful exploration using increasingly sophisticated remote sensing, geophysical, and geochemical survey methodologies.&lt;/div&gt;&lt;div&gt;A contrasting conceptual targeting scenario is provided by critical mineral systems that formed in convergent margin arc settings or in marginal terrestrial sedimentary basins. These include widespread porphyry-skarn Cu-Au-Mo systems, both high- and low-sulfidation epithermal Au-Ag systems, and more geographically restricted IRGD and Carlin-type systems. Where tectonic uplift rates are high, critical metal deposits of these systems are rapidly eroded and have low preservation potential and hence are largely confined to the Cenozoic with only rare systems beyond the late Mesozoic. Conceptual exploration is less challenging for this group as they are commonly situated in mountainous terrains where remote sensing spectral surveys are effective and deposit footprints are large due to v","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100323"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131630","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":"Seasonal impact of particulate matter exposure on urinary health of mine workers in iron ore mining environment","authors":"Vibhanshu Vaibhav Singh ,&nbsp;Aron Rodrick Lakra ,&nbsp;Sneha Gautam","doi":"10.1016/j.geogeo.2024.100342","DOIUrl":"10.1016/j.geogeo.2024.100342","url":null,"abstract":"<div><div>Exposure to particulate matter (PM) in opencast iron ore mines poses a significant health risk to mine workers, particularly impacting urinary health. This study specifically examines how mining activities influence urinary parameters in employees, with a focus on how seasonal variations – such as shifts between monsoon and winter – intensify these effects. Through real-time analysis of air pollutants including PM₁, PM_2.5, PM₁₀, CO₂, and HCHO, we captured critical seasonal fluctuations in pollutant concentrations across different mining departments.</div><div>Urine samples from workers in diverse departments were rigorously analyzed for glucose levels, elemental concentrations, and other health indicators. Advanced regression and correlation analyses revealed strong associations between urine markers and PM exposure, with exceptionally high R² values across departments: 0.984 for excavation, 1.000 for crushing, 0.969 for downhill, 0.963 for screening, and 0.992 for loading, indicating a precise relationship. Low mean squared error (MSE) and root mean squared error (RMSE) values further underscored the model's predictive accuracy. Seasonal variations showed a clear impact on exposure levels, with the overall relevance percentage between monsoon and winter seasons approximating 39.24%, underscoring the added health burden during seasonal transitions. The results indicate that workers' health is clearly affected by exposure to mining-related air pollutants, as shown by the urine analysis, which revealed elevated levels of occupationally relevant elements. These findings highlight the need for proactive air quality monitoring and targeted mitigation strategies in mining environments to protect worker health, offering critical insights for policymakers and occupational health professionals focused on improving safety standards in mining operations.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100342"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143403208","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":"Delineation of concealed banded iron formations (BIFs) below the Kurnool sediments in Palnadu Sub-basin, Macherla region, Cuddapah Basin through 3D inversion of aeromagnetic data","authors":"D. Seshu,&nbsp;K․Satish Kumar,&nbsp;P. Sivasankar,&nbsp;Prakash Kumar","doi":"10.1016/j.geogeo.2025.100357","DOIUrl":"10.1016/j.geogeo.2025.100357","url":null,"abstract":"<div><div>Long linear high-intensity aeromagnetic anomalies are observed south of Vijayapuri to Macherla region, Cuddapah basin. The source of these magnetic anomalies is exposed and concealed BIFs with alternate layers of magnetite and quartzite. These BIFs are associated with greenstone belts of the Archean age capped by Kurnool and Cuddaph sediments. The review studies of the present work observed the (i) NW-SE, NE-SW, N-S and E-W trending magnetic linear features corroborated with the identified structural features, (ii) three bipolar magnetic zones (A, B and C) are identified from south of Vijapuri to Macherla, (iii) the nature of the magnetic anomalies at the south of Vijayapuri and south of Macherla alike and existing structural fabric might be responsible for the presence of different characteristics of the anomalies in these regions, (iv) 3D analysis of magnetic zones A, B and C show the presence of three isolated causative sources with susceptibility contrast of 0.115 SI existing from the surface to a depth of 2600 m from south of Vijayapuri to Muthukuru. (v) It is inferred from the 3D model studies, exposed BIFs at Vijayapuri region are dipping towards Macherla from the surface to extend up to a depth of 2600 m associated with amphibolites and might consist of alternative layers of magnetite and quartzite. (vi) The expression of NW-SE, NE-SW, N-S and E-W trending surface geological and magnetic structural lineations provided clues to the study area structurally disturbed and the accumulation of sediments in this region.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100357"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143429539","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":"Exploration of quality groundwater through lineament delineation in Okene and its surroudings","authors":"Oluwatoyin Khadijat Olomo,&nbsp;Onimisi Abdulmalik Danga,&nbsp;Abdullateef O. Aliyu","doi":"10.1016/j.geogeo.2024.100350","DOIUrl":"10.1016/j.geogeo.2024.100350","url":null,"abstract":"<div><div>This research addresses the issue of unproductive boreholes in the study area and the limited information on productive aquifers. The challenging geological terrain and dense urbanization necessitate the use of integrated airborne data, namely Landsat remote sensing, geographic information systems, and aeromagnetic data, to map potential groundwater zones in Okene and its surrounding areas. The analysis utilizes remote sensing and geospatial datasets, which are slope, drainage density, and lineament density, along with aeromagnetic data interpretation. Techniques employed are first and second-order derivatives, tilt derivative, and total horizontal derivative to identify groundwater productive zones. Observations of remotely sensed lineaments indicate intersections with aeromagnetic composite lineaments, suggesting the presence of shallow and deeper lineaments in proximity. These intersection points are identified as potential zones for groundwater accumulation and development due to their characteristics of secondary porosity and high permeability. The depth to the aquiferous zone, as determined by 3-D Euler deconvolution and spectral analysis, ranges from 60 to 150 m, which is proposed as the depth for borehole drilling in the study area. The central and southeastern regions of the study area exhibit higher groundwater potential because of the high density of lineament intersection and are recommended for future groundwater development. This study illustrates the effectiveness of geospatial and aerogeophysical techniques in regional groundwater exploration to provide insights into subsurface structural disposition for locating aquiferous zones and improving groundwater management.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100350"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131356","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":"College bus commuter exposures to air pollutants in Indian city: The urban-rural transportation exposure study","authors":"Aron Rodrick Lakra ,&nbsp;Sneha Gautam ,&nbsp;Cyril Samuel ,&nbsp;Robert Blaga","doi":"10.1016/j.geogeo.2024.100346","DOIUrl":"10.1016/j.geogeo.2024.100346","url":null,"abstract":"<div><div>This study analyzes air quality along the Kavundampalayam transit route and across three urban regions in Coimbatore, India – Kavundampalayam, Ganapathy and Kovaiputhur – over five days during morning and evening commutes. Key pollutants monitored include PM₁, PM_2.5, PM₁₀, CO₂, formaldehyde (HCHO), and the Air Quality Index (AQI). Results show that PM_2.5 levels often exceeded the WHO's 24-hour limit, with Kovaiputhur peaking at 120.33 µg/m³ and PM₁₀ concentrations reaching 259.08 µg/m³ in Kavundampalayam. CO₂ levels varied significantly, with Ganapathy recording the highest at 1942.42 ppm, indicating traffic and industrial sources. Morning commutes exhibited higher PM levels due to vehicular emissions, while evenings showed reduced pollution. HCHO concentrations, though low (&lt;0.023 mg/m³), spiked in the evenings, suggesting emission sources later in the day. A strong correlation between CO₂ and AQI underscores the impact of anthropogenic activities on air quality. The study identifies pollution hotspots using heatmaps and temporal patterns, emphasizing the need for interventions like emission control, dust regulation, and green infrastructure. Continuous air quality monitoring is essential for sustainable urban planning, helping policymakers design strategies to reduce exposure risks and improve public health.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100346"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131371","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":"Heavy metal (Pb, Cd and Cr) contamination and human health risk assessment of groundwater in Kuakata, southern coastal region of Bangladesh","authors":"Ali Newaz Chowdhury ,&nbsp;Samsun Naher ,&nbsp;Md. Nur Alam Likhon ,&nbsp;Jubairul Hassan ,&nbsp;Zannati Nur Fariha ,&nbsp;Md. Raisul Hasan ,&nbsp;Tanha Dewan Apon ,&nbsp;Md. Anwar Hossain Bhuiyan ,&nbsp;Md Mesbah Uddin Bhuiyan","doi":"10.1016/j.geogeo.2024.100325","DOIUrl":"10.1016/j.geogeo.2024.100325","url":null,"abstract":"<div><div>This study investigates the quality of groundwater in Kuakata, a coastal area in southwestern Bangladesh, by analyzing the levels of lead (Pb), cadmium (Cd), and chromium (Cr) in 50 groundwater samples. The concentrations of these heavy metals were determined using atomic absorption spectrometry. The results indicated that while cadmium was not detected, significant levels of lead and chromium exceeded recommended safety thresholds. The contamination was evaluated using several indices, including the heavy metal evaluation index (HEI), heavy metal pollution index (HPI), and degree of contamination (C_d). Health risk assessments for adults and children revealed potential non-carcinogenic and carcinogenic risks, particularly from lead. This study provides essential data to guide groundwater management and improve public health in the region. The groundwater samples contain traces of additional heavy metals including lead and chromium. The lead concentration ranges from 0.0003 to 0.1049 mg/L, while chromium ranges from 0.00074 to 0.1828 mg/L. The levels of certain substances in groundwater exceeded the maximum limit set by international and local health authorities for safe drinking water. Heavy metal evaluation index (HEI), along with the degree of contamination (C_d) and heavy metal pollution index (HPI), were used to assess the pollution load. The results of HEI and HPI revealed that a significant portion of the samples in the study area, specifically 34% and 38%, were found to be strongly and seriously affected, whereas 38% samples were within the highest values (&gt;4) of C_d. Based on the hazard index (HI) and incremental lifetime cancer risk (ICLR) values, the deep groundwater in the coastal area presents a notable health risk to the local population, particularly children. This study provides essential data that can be used as a foundation for developing effective groundwater management strategies in the coastal region, with the ultimate goal of ensuring the availability of safe drinking water.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 1","pages":"Article 100325"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143131366","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":"Composition of olivines and spinel group minerals in aillikites from the Bushkanay dyke, South Siberian Craton: Insights into alkaline melt sources and evolution","authors":"Yazgul Nugumanova ,&nbsp;Anna Doroshkevich ,&nbsp;Anastasia Starikova ,&nbsp;Jonathan Garcia","doi":"10.1016/j.geogeo.2023.100247","DOIUrl":"10.1016/j.geogeo.2023.100247","url":null,"abstract":"<div><div>The potential sources and conditions that control the formation and evolution of alkaline melts are far from being fully understood. To address some of these fundamental questions, we have focused on the composition of olivines and spinel group minerals in aillikites from the Bushkanay dyke in the Siberian Craton. These ultramafic carbonate-rich lamprophyres contain 40–50 vol% fresh olivine macrocrysts (200–600 µm) within a groundmass consisting of phlogopite (60%), magnetite (15%), perovskite (10%), apatite (5%), calcite (3%), chromite (1%), clinopyroxene (up to 1%), barite (up to 1%), serpentine and chlorite (up to 4%). Two types of compositional zoning in olivine have been recognized: (1) Mg-rich cores consisting of a relatively high #Mg (86-89) and NiO (0.25–0.4 wt%); (2) Fe-rich cores with a relatively low #Mg (82-86) and NiO (0.10–0.25 wt%). Both types of olivine cores are igneous and crystallize from an ultramafic carbonate-rich melt. The Mg#-poor (Fe-rich) cores were derived from an early and more evolved aillikitic melt and were later entrained by a more primitive melt, responsible for the formation of the Mg#-rich (Mg-rich) cores. The spinels exhibit a more complex zoning with four major growth zones: (1) an aluminum chromite core; (2) an Fe-chromite and Cr-magnetite transitional zone; and (3) a Ti-magnetite rim. The most primitive spinels of Al-chromite compositions crystallized directly from undifferentiated pulse of the melt, while further growth involved a gradual decrease in Cr due to the crystallization of Cr-rich spinels, while Al remained the same due to the absence of early phlogopite. Our results on olivines and spinels suggest that the aillikites of the Bushkanay dyke were derived from a phlogopite-bearing carbonatized peridotite source. This idea is also supported by the presence of phlogopite, calcite, and amphibole as major phases in the chromite melt inclusions.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100247"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138991160","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":"Chemical evolution of major and minor minerals in rocks of the Arbarastakh complex (Aldan shield, Republic of Sakha, Yakutia)","authors":"Mikhail Nikolaevich Kruk ,&nbsp;Anna Gennadievna Doroshkevich ,&nbsp;Ilya Romanovich Prokopyev ,&nbsp;Ivan Aleksandrovich Izbrodin","doi":"10.1016/j.geogeo.2024.100271","DOIUrl":"10.1016/j.geogeo.2024.100271","url":null,"abstract":"<div><div>The alkaline-ultrabasic carbonatite complex Arbarastakh is located in the southwestern part of the Siberian Craton. In addition to ultrabasic rocks such as pyroxenites and ijolites, various types of carbonatite dikes, phoscorites, and aillikites are present in the massif. Based on their modal and compositional characteristics, as well as the chemical composition of minerals, the rocks of the Arbarastakh complex have been divided into three groups: \"aillikite\", \"phoscorite\", and \"alkaline-silicate and carbonatite\" groups. The chemical compositions of olivines, phlogopites and spinellides indicate that aillikites are the least differentiated rocks in the complex. The compositional differences of micas from the \"phoscorite\" and \"alkaline-silicate and carbonatite\" groups support the liquation of the aillikite melt into two immiscible silicates and CPIO (carbonate-phosphate/iron-oxide-rich) melts. After liquation, for the \"phoscorite\" and \"alkaline-silicate and carbonatite\" groups, evolution follows fractional crystallization. Pyroxene-phlogopite-calcite and calcite carbonatites probably resulted from metasomatic alteration of silicate phases by apatite-dolomite carbonatites, which is confirmed by structural-textural features and the overlapping compositions of phlogopites, apatites and pyroxenes from calcite carbonatites and those from pyroxenites and ijolites.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"3 4","pages":"Article 100271"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140282740","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}