Geosystems and Geoenvironment最新文献

{"title":"Petrogenesis and tectonic setting of Neoarchean K-rich granitoids in the Zhulagou area: Implications for the crustal maturation of Yinshan Block, western North China Craton","authors":"Xiao Wang ,&nbsp;Jin Liu ,&nbsp;Hai Zhou ,&nbsp;Xiaoguang Liu ,&nbsp;Chenying Yu ,&nbsp;Shuhui Zhang ,&nbsp;Jian Zhang","doi":"10.1016/j.geogeo.2025.100384","DOIUrl":"10.1016/j.geogeo.2025.100384","url":null,"abstract":"<div><div>K-rich granitoids are considered as an indicator of the maturation of the continental crust, particularly in correlation to the significant crustal evolution during the Neoarchean Eon. The Yinshan Block, a typical Neoarchean microcontinental block of the western North China Craton (NCC), preserves several typical K-rich granites (monzogranitic gneisses). However, their petrogenesis and tectonic background of these remain unclear, hindering our understanding of the late Neoarchean crustal evolution of the NCC. This study presents new geochronological, geochemical, and Sr-Nd-Pb-Hf isotopic data on the K-rich granites exposed in the Zhulagou area, a key exposure of the Yinshan Block. Zircon U–Pb dating results suggest that the K-rich granites were emplaced at 2.52–2.50 Ga. The K-rich granites exhibit high SiO₂ (68.70–74.10 wt. %) and K₂O (3.40–7.79 wt. %) and lower MgO (0.24–1.04 wt. %) content. They also have high Sr/Y and (La/Yb)_N ratios, as well as low Y and Yb contents. Furthermore, they display variable <em>ε</em>_Hf(<em>t</em>) (–1.1 to +2.5) and <em>ε</em>_Nd(<em>t</em>) (–6.05 to +1.64) values, with relatively low Pb isotopes (²⁰⁶Pb/²⁰⁴Pb_(t) = (13.910485–15.241164), ²⁰⁷Pb/²⁰⁴Pb_(t) = (14.806723–15.259938), and ²⁰⁸Pb/²⁰⁴Pb_(t) = (33.758621–35.592727)), indicating that their parental magmas may have originated from the partial melting of a thickened lower crust with heterogeneous sources. Combined with previous data, we suggest that a pulse or stage of mantle plume may have been operating under the Yinshan Block during late Neoarchean period. The pre-existing thickened (mafic) lower crust was partially melted to generate these K-rich granites at 2.52–2.50 Ga, resulting in a mature and stable continental crust.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100384"},"PeriodicalIF":0.0,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783526","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":"Redox conditions, solute sources and biogeochemical cycling in the Orosirian ocean: Geochemical and isotopic evidence from stromatolitic carbonates of ∼1.9 Ga Tadpatri Formation, Cuddapah Basin, India","authors":"M. Ashok,&nbsp;Nurul Absar","doi":"10.1016/j.geogeo.2025.100386","DOIUrl":"10.1016/j.geogeo.2025.100386","url":null,"abstract":"<div><div>The Orosirian Period of the middle Paleoproterozoic Era was marked by a decline in atmospheric oxygen and a reducing ocean after a brief oxidized interval of the preceding Great Oxidation Event. Here, we present C<img>O, Nd-Sr isotopic and trace element geochemistry of ∼1.9 Ga stromatolitic Tadpatri Carbonates (TC) to understand the redox condition, solute sources and carbon cycling in the Orosirian ocean. The stromatolite morphology shows deposition under inter-tidal to sub-tidal shallow marine conditions. Varying degrees of dolomitization of low-Mg calcites by an Mg-rich and ¹³C-depleted saline marine fluid at elevated temperature (140–200ºC) and high fluid-to-rock ratios (50–200) significantly modified the depositional C<img>O isotopic composition, and δ¹³C values (–1.5‰ - –2‰) recorded in low-Mg calcite are likely closest to the depositional values. These carbon isotopic values are significantly lower compared to the global Orosirian records. Low U/Th, V/<em>Sc</em>, and Mo/<em>Sc</em> in TC suggest a small seawater inventory of redox-sensitive elements, and in conjunction with high Fe-, Mn- concentrations and absence of Ce-anomaly indicates an anoxic- ferruginous ocean. High radiogenic εNd_1.9Ga values (–5.6 - –3.9) of TC compared to the older Dharwar Craton (–9.6) suggest solute sources from a juvenile crust or mantle-derived hydrothermal fluids. Very high U/Th and V/<em>Sc</em> in the Lower Vempalle Formation suggest oxidized conditions at ca. 1999 Ma, and progressive upward decrease of U/Th and V/<em>Sc</em> in the Middle-, Upper-Vempalle and Tadpatri Formations to much lower levels indicate a drawdown in atmospheric <em>p</em>O₂ level.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 3","pages":"Article 100386"},"PeriodicalIF":0.0,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mapping of hematite ore deposits using multi-sensor data in the Sekota District, Northern Ethiopia","authors":"Jerbaw Tiruneh Abejehu ,&nbsp;Binyam Tesfaw Hailu ,&nbsp;Worash Getaneh ,&nbsp;Karuturi Venkata Suryabhagavan","doi":"10.1016/j.geogeo.2025.100385","DOIUrl":"10.1016/j.geogeo.2025.100385","url":null,"abstract":"<div><div>Iron plays a vital role in fueling the economic development and technological advancement of a country. Despite Ethiopia, being endowed with a large amount of iron ore resources in different parts of the country, prospective zones are not delineated properly. Therefore, this study aims to identify the iron ore prospective zones in the Sekota district of Ethiopia utilizing ASTER and Sentinel−2A satellite data for further onsite exploration and testing. In addition, powder diffraction analysis (XRD) was conducted to determine the dominant mineralogical phases. The image processing techniques such as ASTER band 2/band 1 (ASB2/B1) and Sentinel−2A band 4/band 2 (S2B4/B2) band ratios, principal component analysis (PCA), and subpixel level mapping technique, mixture-tuned matched filtering (MTMF) were used to map the distribution of hematite. ASB2/B1 and S2B4/B2 band ratios mapped hematite iron ore covering an area of 102.50 and 97. 68 km². The selected PC4 of ASTER delineated hematite mineralized zones covering 133.40 km² and Sentinel 2 PC3 of 110.70 km² area. A very high spectral feature fit was found between the extracted hematite endmember and USGS resampled hematite spectra. The spectral fit of the endmember was 0.74 for ASTER and 0.86 for Sentinel−2. Hematite anomaly zones were identified with MTMF using these endmembers in different parts of the study area. Powder X-ray diffraction analysis (XRD) revealed high hematite phases ranging from 36.8%−85.5% of Fe₂O₃. A strong positive correlation was found between S2B4/B2 and S2B4/B2 (<em>r</em> = 0.83), ASB2/B1 and ASTER PC4 (<em>r</em> = 0.94). Moderate correlations for ASB2/B2, S2B4/B2 (<em>r</em> = 0.44), PCA (<em>r</em> = 0.44), ASTER and Sentinel−2 MTMF (<em>r</em> = 0.36). Results of both datasets show comparable areal coverage and overlay with three of the existing known iron occurrence polygons. Thus, it is evident that techniques employed are effective in narrowing hematite anomalies zones for further onsite gological exploration.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100385"},"PeriodicalIF":0.0,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776390","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":"Introduction: Special Issue on critical metals for clean energy transition","authors":"Jie Zhou ,&nbsp;David I. Groves","doi":"10.1016/j.geogeo.2025.100382","DOIUrl":"10.1016/j.geogeo.2025.100382","url":null,"abstract":"","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100382"},"PeriodicalIF":0.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739192","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":"Source-to-sink history of detrital garnet from coastal dune sands in SW Mexico","authors":"Lizeth Carlos Delgado ,&nbsp;Juan J. Kasper-Zubillaga ,&nbsp;Raymundo G. Martínez-Serrano ,&nbsp;Mayumy Amparo Cabrera Ramírez ,&nbsp;Elsa Arellano-Torres ,&nbsp;José Luis Sánchez Zavala","doi":"10.1016/j.geogeo.2025.100381","DOIUrl":"10.1016/j.geogeo.2025.100381","url":null,"abstract":"<div><div>A morphological and geochemical study of detrital garnet was conducted to assess its utility in understanding sedimentary processes in coastal dune sands caused by in a weathering-limited erosion regime along the southwestern coast of Mexico. Multiple analytical techniques helped to elucidate the garnet's provenance, shape modification and surface alteration during its source-to-sink sedimentary dispersal. A Wavelength Dispersive Spectrometry (WDS) in an Electron Microprobe Analyzer (EMPA) (n = 89) revealed the dominance of almandine as the main mineral type related to the ortho-paragneiss source rocks from the Oaxacan Complex with a lesser contribution from the Xolapa Complex, outcropping in northwestern of the coastal dune sands. Scanning Electron Microscopy (SEM) helped to assess the compactness and convexity of shape descriptors by contouring the outline of detrital garnet (n = 200) and to identify the microtextures of the mineral's surface. A Raman Spectroscopy (n = 17) was employed to determine the presence of hydroxide or oxyhydroxide coatings to quantify the chemical weathering degree caused by steady and shallow burial conditions. Results show that the detrital garnet mainly underwent aeolian abrasion followed by fluvial subaqueous and marine controls. The former was supported by the quantification of moderate to high compactness and convexity values and the SEM observation of aeolian mechanical microtextures like bulbous edges, adhering particles and abrasion fatigue compared to the subaqueous microtextures as large conchoidal fractures (&gt;50 µm). Finally, we found that low to moderate chemical dissolution control modified the detrital garnet's surficial texture, evidenced by chemical microtextures like solution pits, etch pits, etch features, imbricate wedge marks and mound features. Hence, detrital garnet dissolution was dominated by its chemical composition, the nonstoichiometric character of the dissolution rate and its crystallographic forms.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100381"},"PeriodicalIF":0.0,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739193","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":"Biotite as a petrogenetic discriminator in the polymetamorphosed rocks: A case study from the Champaner supracrustal rocks, Western India","authors":"Parita K. Gorania ,&nbsp;Gayatri N. Akolkar ,&nbsp;Aditya U. Joshi ,&nbsp;Manoj A. Limaye ,&nbsp;Mahendra K. Singh","doi":"10.1016/j.geogeo.2025.100380","DOIUrl":"10.1016/j.geogeo.2025.100380","url":null,"abstract":"<div><div>The mineral chemistry of Fe-Mg biotite has served as an aid to the petrogenesis of igneous rocks, especially for identifying the parent magma compositions. Though the interpretation of igneous and metamorphic processes utilizing biotite mineral chemistry is not upfront, it certainly provides preliminary insights into the petrogenetic characteristics of rocks. Apart from thermometry and chronology, studies emphasizing on the significance of biotite mineral chemistry for unveiling the protolith compositions, grade of metamorphism, origin, and P-T conditions of metamorphic rocks are poorly documented in the literature. Here we employ biotite mineral chemical compositions i.e., EPMA (electron probe micro-analyzer) data from the metapelitic rocks of the Meso-Neoproterozoic Champaner Group, exposed as an arcuate fold belt in western India to unravel the metamorphic rock record. This group of rocks display a complex deformational and polymetamorphic history, evident in distinct mineral assemblages that reflect regional, contact, and combined regional-contact metamorphism. The field observations, mesoscopic features of rocks, reaction textures, and biotite petrographic characteristics have revealed three distinct varieties of metapelitic rocks i.e., phyllites, spotted phyllites, and hornfelses. The mineral chemistry and cation substitution mechanisms of biotite selected from phyllite, spotted phyllite and hornfels suggests, the chemical composition of biotite in these rocks is a function of the bulk rock composition, co-existing minerals, type, and grade of metamorphism and thereby attesting to the pressure-temperature conditions of rock. Further, various compositional classification diagrams and Ti-in biotite thermometry demosntrate an increase in the grade of metamorphism from west to east of Champaner Group with intermittent as well as late-stage plutonic felsic intrusions. Thus, biotite being frequently the dominant or sometimes even sole Fe-Mg mineral with temperature-pressure driven substitutions in low-grade metamorphic rocks can offer a unique opportunity to unlock valuable insights into their metamorphic history.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100380"},"PeriodicalIF":0.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715357","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":"Ozone patterns in Maceió: Insights into seasonal and geographic varibility","authors":"Amaury de Souza ,&nbsp;Celina M. Takemura ,&nbsp;Deniz Özonur ,&nbsp;Elias Silva de Medeiros ,&nbsp;Ivana Pobocikova ,&nbsp;Janice F. Leivas ,&nbsp;José Francisco de Oliveira-Júnior ,&nbsp;Kelvy Rosalvo Alencar Cardoso ,&nbsp;Marcel Carvalho Abreu ,&nbsp;Wagner Alessandro Pansera ,&nbsp;Jose Roberto Zenteno Jimenez ,&nbsp;Sneha Gautam","doi":"10.1016/j.geogeo.2025.100379","DOIUrl":"10.1016/j.geogeo.2025.100379","url":null,"abstract":"<div><div>This study analyzes the Total Ozone Column (TCO) over six cities in Alagoas, Brazil, aiming to evaluate their spatial and temporal homogeneity and identify seasonal and annual patterns from 2008 to 2016. TCO is a key indicator for monitoring the ozone layer and its implications for public health, given ozone's role in filtering ultraviolet radiation. The analysis utilized satellite-derived TCO data, with variance homogeneity assessed using the Bartlett test at a 95% significance level. Descriptive statistical analyses characterized the temporal distribution of TCO values, and probability density functions (PDFs) identified the best-fitting statistical distribution.</div><div>The findings indicate significant homogeneity in annual and seasonal TCO concentrations, with an annual mean of 263.24 ± 9.91 DU. A biannual TCO cycle was observed, with peaks in spring and lows in fall, influenced by Earth's orbit and ozone photochemistry. The data were best represented by a normal distribution, reflecting the role of the Brewer-Dobson Circulation in maintaining ozone uniformity and mitigating disruptions from phenomena like the Antarctic Polar Vortex.</div><div>These results emphasize the need for continuous monitoring of ozone variability, as fluctuations in TCO can affect ultraviolet radiation levels and, consequently, public health outcomes such as skin cancer and ocular diseases. The study underscores the importance of integrating TCO data into environmental policies and public health strategies, particularly in regions with high solar radiation exposure. The study's limited statistical sensitivity and geographic coverage highlight the necessity of further research on factors influencing ozone distribution and its broader environmental and health implications.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100379"},"PeriodicalIF":0.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684300","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":"Assimilation of seismic attenuation model of NW Himalaya and its surrounding region","authors":"Vandana,&nbsp;Naresh Kumar","doi":"10.1016/j.geogeo.2025.100378","DOIUrl":"10.1016/j.geogeo.2025.100378","url":null,"abstract":"<div><div>In this study, we analyze the seismic attenuation characteristics of the Northwest Himalaya and adjacent regions using a dataset of 2,716 earthquakes (2.5 ≤ Mw ≤ 5.0) recorded from 2008 to 2015 by a network of 30 broadband seismographs. The single backscattering model was applied to estimate the quality factor of coda waves (<em>Q_c</em>) across three lapse time windows (LTWs) at varying frequencies. Our results reveal that <em>Q_c</em> increases with both frequency and LTW, suggesting a depth-dependent nature of seismic attenuation in the region. The average attenuation relationships for <em>Q_c, Q_α</em> and <em>Q_β</em> across the Northwest Himalaya are determined as follows for LTWs of 20, 30, and 40 s, respectively: <em>Q_c</em> = (74 ± 14)<em>f</em> ^(1.27±0.06), <em>Q_c</em> = (103 ± 26)<em>f</em> ^(1.16±0.08), and <em>Q_c</em> = (140 ± 41)<em>f</em> ^(1.10±0.09). Our findings reveal significant variability in <em>Q_c, Q_α</em> and <em>Q_β</em> across the Tethys (TH), High (HH), Lesser (LH), and Shiwalik (SH) Himalaya regions, as well as the adjacent Indo-Gangetic Plains (IGP), with this variability strongly linked to structural heterogeneity and seismogenic processes in each region. We further establish attenuation relations for distinct tectonic units, observing the following hierarchy: [<em>Q_α,β,c</em>⁻¹(HH) &lt; <em>Q_α,β,c</em>⁻¹(SH) &lt; <em>Q_α,β,c</em>⁻¹(IGP) &lt; <em>Q_α,β,c</em>⁻¹(LH) &lt; <em>Q_α,β,c</em>⁻¹(TH)]. The Tethys Himalaya exhibits the high attenuation, likely due to its sedimentary structure, while the Higher Himalaya shows the low attenuation. These insights into attenuation characteristics across geotectonic segments in the Northwest Himalaya contribute to a more comprehensive seismic hazard assessment for the region.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100378"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684299","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":"Geohazard impact and gas reservoir pressure dynamics in the Zagros Fold-Thrust Belt: An environmental perspective","authors":"Mahsa Asghari ,&nbsp;Zahra Maleki ,&nbsp;Ali Solgi ,&nbsp;Mohammad Ali Ganjavian ,&nbsp;Pooria Kianoush","doi":"10.1016/j.geogeo.2025.100362","DOIUrl":"10.1016/j.geogeo.2025.100362","url":null,"abstract":"<div><div>The Zagros Fold-Thrust Belt (ZFTB) presents a unique intersection of geohazards and gas reservoir dynamics, shaped by the ongoing tectonic activity resulting from the collision of the Arabian and Eurasian plates. This study aims to assess the risk of earthquake-induced landslides and their impact on gas reservoir pressure dynamics – with a particular focus on the Kabir Kuh gas field – identified as a critical area for monitoring due to its vulnerability to seismic events. A novel hybrid model is introduced that integrates geographic information system (GIS) mapping, decision support system (DSS) modeling, and machine learning algorithms. By analyzing a century's worth of seismic data alongside real-time environmental parameters, the model demonstrates a predictive accuracy of 92% using Random Forest algorithms, significantly outperforming traditional methods. The findings reveal a strong correlation between seismic activity and fluctuations in gas reservoir pressure, with an average pressure change of ±150 psi observed during significant seismic events. A landslide susceptibility map was generated, pinpointing regions that require proactive management strategies, particularly where significant landslide potential threatens gas field stability. Identifying the Seymareh landslide as a monumental geological event underscores the impact of landslide hazards on gas field integrity. This research emphasizes the integration of advanced predictive techniques into seismic risk assessments, providing actionable insights for the sustainable gas reservoir management in seismically active regions. The necessity for continuous monitoring and the implementation of advanced geotechnical measures are highlighted as essential components of effective geohazard management. This study contributes to understanding the interplay between seismic hazards and gas reservoir dynamics, offering a comprehensive framework for future research and practical applications in risk management and environmental sustainability.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100362"},"PeriodicalIF":0.0,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562425","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":"Petrogenesis of gneisses and granitoids from Southern Bastar Craton, India: A geochemical insight to crustal evolution","authors":"Soumya Mitra ,&nbsp;Santa Dolui ,&nbsp;Asutosh K Tripathy","doi":"10.1016/j.geogeo.2025.100377","DOIUrl":"10.1016/j.geogeo.2025.100377","url":null,"abstract":"<div><div>This study investigates the geochemical evolution and petrogenesis of gneisses and granitoids from the southern part of the Bastar Craton, India, to understand the crustal evolution. The study incorporates the result on major, minor, trace and rare earth elements (REE) interpretation. The gneisses, classified as high alumina granodiorite to granite, peraluminous and exhibit geochemical signatures typical of Archaean TTGs, including enrichment in large ion lithophile elements (LILE) and depletion in high field strength elements (HFSE) with notable negative anomalies in elements like Nb, P, and Ti. In contrast, the granitoids show a meta-aluminous to per-aluminous composition, with higher K₂O/Na₂O ratios and pronounced enrichment in LILE with higher Sr, Ba, Zr, Nb, Y and Yb contents than the gneisses. These patterns suggest a progressive geochemical evolution from gneiss to granitoids. The study put forward two distinct subduction phases contributing to the formation of these rocks. The initial phase associated with a pre- to syn-collisional tectonic setting in a flat low-angle subduction at shallower depth and minimal interaction between slab melts and the mantle wedge. Whereas, the later one is characterized by a collision to subduction transition in a post-collisional setting with gradual increase in mantle-wedge interaction at a relatively greater depth, involving a steeply dipping subduction process. This dual-phase subduction model highlights the tectonic shift in the region over time and provides a comprehensive understanding of the geological evolution of the Bastar Craton.</div></div>","PeriodicalId":100582,"journal":{"name":"Geosystems and Geoenvironment","volume":"4 2","pages":"Article 100377"},"PeriodicalIF":0.0,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636765","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}