Ore and Energy Resource Geology最新文献

{"title":"Spatial heterogeneity of soil potassium geochemistry: A case study from Tianfu New Area, Chengdu, China","authors":"Fan Meng ,&nbsp;Yang Wu ,&nbsp;Liang Tang ,&nbsp;Fang Yang ,&nbsp;Lingfei Qu ,&nbsp;Yang Li","doi":"10.1016/j.oreoa.2024.100054","DOIUrl":"10.1016/j.oreoa.2024.100054","url":null,"abstract":"<div><p>Urban-rural integration zones, situated at the interface between urban and rural environments, undergo profound alterations in arable soil quality attributed to rapid urbanization and intensified agricultural practices. However, there is still insufficiency research on potassium depletion from a spatial perspective, despite the increasing demand for vegetables. To address this gap, the spatial distribution characteristics of soils potassium in Tianfu New District, Chengdu Plain, China, were studied based on geochemistry, geostatistics and Earth system science. The results showed that: (1) Spatial heterogeneity existed in both soil total potassium (STP) and soil available potassium (SAP). However, there was no obvious spatial correlation between STP and SAP, and their spatial extents exhibited minimal overlap. (2) The STP levels are mainly affected by the altitude, slope, stratum exposure and geological background. (3) The SAP content is obviously affected by anthropogenic input, and the enrichment is significantly affected by fertilizers. This study reinforces the notion that the human intervention has strongly affected arable soil quality. The availability of fertilizer (e.g., potash) may significantly affecting food security within China.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100054"},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141030254","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":"Abnormal enrichment of Th and U in melanosome of migmatite in Jivumdnubanda, Eastern Dharwar Craton, India: A unique occurrence in the world","authors":"Sukanta Goswami ,&nbsp;Sudhiranjan Swain ,&nbsp;Ravi Prakash Tiwari ,&nbsp;V. Natarajan ,&nbsp;B. Saravanan","doi":"10.1016/j.oreoa.2024.100055","DOIUrl":"10.1016/j.oreoa.2024.100055","url":null,"abstract":"<div><p>The Neoarchaean (∼2.7Ga) migmatite melanosome of Jivumdnubanda area comprises anomalous radioactive elemental concentration. Significant amount of Th (68.54–290.85 ppm) and U (29.68–114.47 ppm) is observed within biotite-rich melanosome as inclusions. Radioelements are concentrated in certain accessory minerals e.g., allanite, apatite, xenotime and zircon. Leucosomal counterparts are devoid of such higher radioactive elemental concentration, which makes the study significant because the incompatible elements as well as the accessory minerals tend to go into the melt phases more preferentially. Each component of migmatite e.g., melanosome, leucosome and the diatexites are studied in detail from outcrops, under an optical microscope and by geochemical analysis. Structural deformation aspects are also taken care along with granite age determination to link the diatexite with anatexis timing. It is found that the migmatites formed around a pressure of ∼600 MPa correspond to a ∼20–22 km crustal depth when the hydrous mineral breakdown led to ∼50 % melting of evolved TTG protolith. Radiation-induced damage of the accessory minerals due to alpha decays destroyed the internal crystal structures at places. This metamictization and associated radiation damage of more or less refractory minerals along with deformation associated grain-scale fractures make easier to release mobile uranium during hydration and associated alteration at later stage. The presently observed radioactive elemental concentrations are the remnants left behind in the melanosome after leaching out of significant uranium.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100055"},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141049757","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":"Hydrogeochemical arsenic simulation of V-Ti-Fe tailings pond ecosystem: A case study from Panxi region, China","authors":"Feng Jiang ,&nbsp;Lu Sun ,&nbsp;Fang Yang ,&nbsp;Liang Tang ,&nbsp;Ke Cheng ,&nbsp;Nengjian Zheng ,&nbsp;Yang Li ,&nbsp;Meng Hou","doi":"10.1016/j.oreoa.2024.100053","DOIUrl":"10.1016/j.oreoa.2024.100053","url":null,"abstract":"<div><p>The V-Ti-Fe mine tailings waste releases high concentrations of aquatic arsenic (As) ions to downstream ecosystems. The hydrogeochemical As simulation facilitates the prediction of toxicity (or redox state) and devising control strategies to mitigate the negative impacts. Therefore, this study utilizes the Wanniangou tailings pond (a V-Ti-Fe mine tailings reservoir) in the Panxi region, Sichuan province, China, as a case study to elucidate the As hydrogeochemical behaviour under varying pH and redox potential (Eh) conditions. Our study reveals that (1) the water-oxygen exchange and Mn are important to regulating the redox conditions in the filtrates. The Eh determines the valence states of As, which vary from reduced states to oxidized states during the runoff from the tailings pond to downstream (Rehe River). The flow of wastewater in Rehe River minimizes both the As toxicity and concentration, eventually improving water safety. (2) In a reducing environment, hematite exhibits a limited capacity for As(III) adsorption. In the case of oxidation conditions, goethite mainly adsorbed As(V), with an elevated adsorption capacity. Meanwhile, Fe-minerals remain relatively stable under varying redox and weakly acidic conditions. Consequently, targeted engineering interventions can achieve two crucial outcomes: (1) Minimize the acidity of the mine environment to retard the release of heavy metals from the tailings waste. (2) Prolonging the residence time of wastewater in Rehe River to promote the transition from a reducing state to an oxidizing state, thereby synergistically mitigating As toxicity.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100053"},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666261224000154/pdfft?md5=caefa12c6dfd0ce36348a3f53e0fafb5&pid=1-s2.0-S2666261224000154-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141039368","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":"Altered spinels act as a mirror of multi-episodic fluid metasomatism in the forearc mantle: An example from the Minhe ophiolite in Qilian Orogen, NW China","authors":"Jing Zhao ,&nbsp;Xiaoping Long","doi":"10.1016/j.oreoa.2024.100052","DOIUrl":"https://doi.org/10.1016/j.oreoa.2024.100052","url":null,"abstract":"<div><p>Forearc mantle peridotites commonly undergo complex melt/fluid metasomatism, which inevitably has a considerable influence on their geochemical compositions at the whole-rock scale. Serpentinites predominantly comprise the Minhe ophiolite, which is a fragment of the Proto-Tethys Ocean that outcrops in the Qilian Orogen in NW China. These serpentinites contain zoned spinels that vary compositionally from the centers to the margins, with a spinel core overgrown by ferritchromite layer and magnetite at the outermost rim. The mineral chemistry of the spinel cores (i.e., Cr^#, Mg^#, Cr₂O₃, and Al₂O₃) suggests that the protolith of the serpentinites was an oceanic mantle remnant in a forearc setting. Moreover, the ferritchromite exhibited increases in Fe, Mn, Sc, and Ni contents and decreases in Mg, Cr, Al, V, Zn, and Ga contents. Considering the linear correlation among elements (e.g., Co, Ni, and Zn) and the absence of mineral inclusions, the ferritchromite likely formed through ionic substitutions induced by slab fluids. The magnetite was enriched in Cr, Ni, V, Zn, Co, and Cu, but did not have a magmatic origin owing to low V concentrations. All evidence indicates that the peridotites underwent at least two episodes of fluidic metasomatism in the subduction zone. During early slab subduction, aqueous fluids released from the dehydration of the subducted slab directly serpentinized the forearc mantle peridotites, thereby altering the olivine and orthopyroxene to lizardite/chrysotile. During this process, certain mobile elements (e.g., Fe, Ni, and Mn) in the fluids and/or olivine serpentinization were incorporated into existing spinels, favoring ferritchromite growth. The second fluidic episode was dependent on prograde metamorphism at greater depths in the subduction channel, which not only produced antigorite via the recrystallization of lizardite and chrysotile, but also drove the fluids towards a more oxidizing state, thereby facilitating the growth of Cr-magnetites. Subsolidus re-equilibration controlled by fluid infiltration further promoted the inter-diffusion of elements (e.g., Cr, V, Co, Ni, Cu, and Zn) in the zoned spinels.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100052"},"PeriodicalIF":0.0,"publicationDate":"2024-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140894098","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":"Geochemistry of the Winneba-Mankoadze pegmatites in Southern Ghana: A clue to the petrogenesis of the pegmatites","authors":"Salaam Jansbaka Adams ,&nbsp;Emmanuel Daanoba Sunkari ,&nbsp;John Emmanuel Kobina Hanson ,&nbsp;Kingsley Kwaah Tandoh ,&nbsp;Samuel Edem Kodzo Tetteh ,&nbsp;Prosper Mackenzie Nude ,&nbsp;Daniel Kwadwo Asiedu ,&nbsp;Samuel Boakye Dampare","doi":"10.1016/j.oreoa.2024.100051","DOIUrl":"10.1016/j.oreoa.2024.100051","url":null,"abstract":"<div><p>The Birimian Supergroup (2195–2135 Ma) of Ghana was affected by the Eburnean Tectono-thermal Event at approximately 2195 Ma. The latest stage of this event resulted in pegmatitic veining in the Birimian Supergroup of Ghana at 2072 Ma. Deposits of pegmatites have been reported by many researchers in the south-western coast of Ghana. However, their mineralogy and economic potential remain fully unexplored. This study determined the geochemical characteristics and mineralogical composition of the pegmatites in the Winneba-Mankoadze area using field observations, petrographic studies, and major and trace element data. From the field work and petrographic data, the pegmatites can be classified as rare-element type, LCT family. The modal composition of the major minerals are spodumene (0.0–30.0 %), muscovite (0.0–20.0 %), garnet (0.0–5.0 %), microcline (0.0–20.0 %), plagioclase (6.0–70.0 %), and quartz (20.0–85.0 %). The geochemical data indicates that the pegmatites are enriched in Rb (2.8–3465 ppm), Cr (22–1803 ppm), Sr (1.2–314 ppm), Ba (13–501 ppm) and the light rare-earth elements (LREE). The pegmatites are highly fractionated accounting for the enrichment in the LREE than the MREE and HREE. They are also depleted in K and Ti. The pegmatites are peraluminous with calc-alkaline trend and are late-orogenic to post-orogenic. Therefore, the source of the pegmatites is the Birimian meta-sedimentary rocks, and the source lithology is upper-to-middle crust supracrustal rocks.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100051"},"PeriodicalIF":0.0,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140793992","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":"Spatial distribution of mine areas in the Luanhe River Basin, China: Clustering implications","authors":"Jingjing Li ,&nbsp;Liang Tang ,&nbsp;Jinsong Yang ,&nbsp;Lingfei Qu ,&nbsp;Fan Meng ,&nbsp;Feng Jiang ,&nbsp;Lei Xu ,&nbsp;Sijie He","doi":"10.1016/j.oreoa.2024.100049","DOIUrl":"https://doi.org/10.1016/j.oreoa.2024.100049","url":null,"abstract":"<div><p>The Luanhe River Basin is the most mined region in China, and spatial analysis of mine areas is beneficial for identifying hotspots of mining-related threats and assessing their impacts in this catchment. From an Earth system science perspective, we examined the spatial clustering of mine areas and the interactions between geographical attributes in the Luanhe River Basin. The findings are: (1) the total mine areas in the Luanhe River Basin are approximately 368.5 km² (2749 polygons), primarily located in the middle and lower reaches. (2) The Global Moran's I for scale and mining land of mine areas in the Luanhe River Basin is 0.04 and 0.45, respectively. This indicates that the scale of mine areas is randomly spread in the basin, while the mining exhibits clustering property. Consequently, clustered mine areas cover approximately 207 km² (56.1 %), while randomly distributed mine areas cover ∼161.5 km² of land (43.9 %). (3) A merged region is formed when the buffer distance of mine areas exceeds 2 km, potentially creating contiguous mining threat areas. This research provides a dataset for managing and governance mine areas in the Luanhe River Basin.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100049"},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140638437","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":"Petrogenesis of cassiterite-rich greisens from Guengue hill, Mayo Darlé, Northwestern Cameroon","authors":"Pemha Nyemb Sayom ,&nbsp;Bravo Martin Mbang Bonda ,&nbsp;Bayiga Elie Constantin ,&nbsp;Mbai Simon Joel ,&nbsp;Ngon Ngon Gilbert François ,&nbsp;Nono Foudje Romaric Noël ,&nbsp;Essono Eric ,&nbsp;Etame Jacques","doi":"10.1016/j.oreoa.2024.100050","DOIUrl":"https://doi.org/10.1016/j.oreoa.2024.100050","url":null,"abstract":"<div><p>The studied cassiterite-rich greisens of Mayo Darlé are hosted in granites located on the NE slope of the Guengue hill. They have three various structural forms including massive, vein, and stockwork. This study aims to describe all the different structural forms of greisen and also explains the main processes of greisen deposition related to the tin mineralization. The petrographic study shows that the massive form presents two facies: the massive greisens are rich and barren in cassiterite respectively; the stockworks and veins are all mineralized. The mineralogical composition recorded for each of the forms are Quartz + Muscovite + Cassiterite + Zinnwaldite + Plagioclase for the cassiterite-bearing greisen; Quartz + Muscovite + Tourmaline + Chlorite for the barren greisen and Quartz + Muscovite + Cassiterite + Tourmaline + Chlorite for the veins and stockworks. This mineralogy could indicate a varied chemical nature of the hydrothermal/magmatic fluids and the host granite. Also, the presence of minerals such as tourmaline, zinnwaldite and chlorite can equally indicate that there were three main stages in the granitic process: (i) tourmalinization, (ii) lepidolitization, and (iii) chloritization. The greisens have a chemical composition rich in SiO₂ (over 71 %) and Al₂O₃ (5.23–43 %). The chondrite-normalized REE pattern shows a negative Eu anomaly (0.0005–0.15) resulting from the disappearance of feldspars and biotite from the geochemical system, which is gradually transformed to quartz and chlorite respectively during leaching. The ratios of Rb/Sr, Zr/Hf, and Nb/Ta indicates an M-type tetrad effect, which also characterizes the variable values of the Eu anomaly. From a mining point of view, the areas most suitable for further prospection would be those hosting the massive, cassiterite-rich greisens. The significant occurrence of tourmaline and zinnwaldite in the studied greisens could indicate a possible Sn–W–Li polymetallic deposit.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100050"},"PeriodicalIF":0.0,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140638436","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":"Ore-forming material sources of the Pakbeng gold deposit, Laos: Evidence from fluid inclusions, H-O-S isotopes, and trace elements","authors":"Hong Liu ,&nbsp;Shuyi Dong ,&nbsp;Yinglei Liu ,&nbsp;Xiaoyu Lin ,&nbsp;Yuhan Liu ,&nbsp;Hu Wang ,&nbsp;Yu Zhao ,&nbsp;Jie Zhang ,&nbsp;Xuexing Xie","doi":"10.1016/j.oreoa.2024.100047","DOIUrl":"10.1016/j.oreoa.2024.100047","url":null,"abstract":"<div><p>The Pakbeng gold deposit, located at the junction of the eastern Tethys and western Pacific tectonic domains, is part of the Phôngsali-Luang Prabang-Sayaboury polymetallic metallogenic belt. Its gold ore bodies are predominantly governed by fault structures, being vein-like and short-axis-veined in shape. The Pakbeng gold deposit primarily exhibits two types of mineralized alterations: the quartz-vein type and the schistositized altered rock type. The ore bodies are primarily distributed within cataclastic granites and altered andesite plutons, near their contact zone. The ore-forming process can be divided into four stages: quartz + rutile + pyrite (stage I), quartz + pyrite + coarse-grained arsenopyrite (stage II), quartz + polymetallic sulfides + native gold (stage III), and calcite + quartz (stage IV). Native gold primarily occurs as invisible gold in the quartz and pyrite of stages I and II, and as enclosed, intergranular, and interstitial gold within the quartz, pyrite, and other metal sulfides of stage III. The ore-forming materials of the Pakbeng gold deposit primarily originate from plagioclase granites and altered andesites, as indicated by investigations of gold-bearing quartz fluid inclusions, hydrogen and oxygen isotopes, the trace-element composition of pyrite, and <em>in situ</em> sulfur isotopes. The sulfur in the deposit is mainly derived from metamorphic sources, supplemented by late magmatic sulfur. The ore-forming fluids in the deposit were dominated by metamorphic fluids in the early stage, with magmatic fluids participating in the late stage. While ascending, the temperature of the ore-forming fluids decreased due to fluid boiling and mixing, but their salinity increased slightly. The ore-forming fluids exhibited a consistent decrease in homogenization temperatures from stages I to IV, with salinity initially increasing and then decreasing. This suggests that the ore-forming fluids are low-temperature, medium to low-salinity and low-density fluids.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"17 ","pages":"Article 100047"},"PeriodicalIF":0.0,"publicationDate":"2024-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140401425","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":"Relationship between the genesis of Changlinggang alkaline rocks and uranium mineralization in the 414U-Th deposit, Jianshui County, Yunnan Province, China","authors":"Suheng Zhang ,&nbsp;Zhengqi Xu ,&nbsp;Yingjun Liu ,&nbsp;Minghui Yin ,&nbsp;Wenbo Zhu ,&nbsp;Shiwen Guo ,&nbsp;Xiaokun Huang ,&nbsp;Lei Kan ,&nbsp;Guangbin Wu ,&nbsp;Yi Luo ,&nbsp;Tiansong Jiang","doi":"10.1016/j.oreoa.2024.100046","DOIUrl":"https://doi.org/10.1016/j.oreoa.2024.100046","url":null,"abstract":"<div><p>Alkaline rocks identified in the 414 U-Th deposit in Jianshui County, Yunnan Province, exhibit intense spatial correlation with uranium mineralization. However, limited investigations into their genesis have had an adverse impact on our understanding of uranium mineralization. Analyses of major and trace elements, U-Pb chronology, and petrography were conducted on alkaline rocks. The results indicate that anorthosite, which is rich in alkalis, high in potassium, peraluminous, enriched in rare earth elements (U, Th, Rb, and Zr) and deficient in Sr, Ba, Ti, and P, predominates the lithology. The light and heavy rare earth fractionation of the material is readily apparent (LREE/HREE=7.89–46.72), and the presence of Eu negative anomalies (δEu=0.65–0.81) suggests that the region from which the magma originated is a metasomatism-enriched mantle where the source material originates from the transition zone between garnet-lherzolite and spinel-lherzolite in the EMII-enriched lithospheric mantle. This area underwent metasomatization by subduction material from the Paleo-Pacific Ocean and during the ascent process, magma experienced a certain degree of partial melting and a significant degree of crystallization differentiation. The diagenesis of the syenite (186.64 ± 3.76 Ma) occurred after the closure time of the Paleotethys Ocean (237 Ma) in a dynamical context of an intra-terrestrial rift environment following subduction of the oceanic plate. In summary, the U and Th present in the 414 U-Th deposits underwent isomorphism within biotite and feldspars during the hydrothermal mineralization stage of magma evolution, where they were enriched in minerals through the separation and crystallization of alkaline magma.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"16 ","pages":"Article 100046"},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666261224000087/pdfft?md5=b4dad56ac8ab05a10316112770d4cc4a&pid=1-s2.0-S2666261224000087-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140191861","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 role of polyphase deformation in the formation of iron deposits and gold mineralization in the paleoproterozoic nyong complex greenstone belt (Southwestern Cameroon)","authors":"Yannick Saturnin Evina Aboula ,&nbsp;Seyed Tohid Nabavi ,&nbsp;Jonas Didero Takodjou Wambo ,&nbsp;Sylvestre Ganno ,&nbsp;Paul-Desiré Ndjigui","doi":"10.1016/j.oreoa.2024.100044","DOIUrl":"https://doi.org/10.1016/j.oreoa.2024.100044","url":null,"abstract":"<div><p>The Toko-Nlonkeng area is situated in the Nyong Complex of the northwestern Congo craton. In this study, airborne geophysical data (radiometric and magnetic) and structural data (outcrops and core samples) were used to investigate the relationship between structural evolution, iron formation (IFs)-hosted iron ore deposits, and gold mineralization in the Paleoproterozoic Nyong complex greenstone belt in southwestern Cameroon. Magnetic and radiometric trends, combined with field data, show general NE-SW, NW-SE, and E-W directions that correlate with the main gold-bearing structures. The study area has undergone four (04) deformation phases relating to polycyclic metamorphic and magmatic events. The D₁ and D₂ phases are the result of progressive ductile and transpressional deformation; D₃ is a brittle-ductile deformation; and D₄ is essentially brittle with various types of fracture networks late to post-orogenic. The D₃ deformation phase is characterized by constrictive deformation with C₃ shears and meso‑ to mega-P₃-folds, and the main stress axes show φσ₂ &gt; φσ₁&gt; φσ₃, reflecting a shearing tectonic regime with a maximum E-W shortening. This polyphase deformation is derived from the Eburnean/Trans-Amazonian deformation related to the collision between the Congo and São Francisco cratons. The main strain in the structural style of the Nyong Complex appears to be transpressive tectonics. This study reveals that iron ore and gold mineralization were mostly found on the hinges of folds and confirms that folding shear zones controlled the iron ore and gold target in the Nyong Complex and Northeast Brazil. The study proposes an approach to optimize future exploration activity based on the integration of the data.</p></div>","PeriodicalId":100993,"journal":{"name":"Ore and Energy Resource Geology","volume":"16 ","pages":"Article 100044"},"PeriodicalIF":0.0,"publicationDate":"2024-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140181078","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}