Chemie Der Erde-Geochemistry最新文献

{"title":"Critical analysis between the Ossa-Morena Zone and the Galicia-Trás-os-Montes Zone, Iberian Massif: Geochemical and geochronological comparison and geodynamic implications","authors":"P. Cachapuz ,&nbsp;M. Chichorro ,&nbsp;T. Bento dos Santos","doi":"10.1016/j.chemer.2024.126168","DOIUrl":"10.1016/j.chemer.2024.126168","url":null,"abstract":"<div><p>Recent studies have suggested the existence of a correlation between the allochthonous units of NW Iberia (Galicia-Trás-os-Montes Zone - GTMZ) with SW Iberia (Ossa-Morena Zone – OMZ) in the European Variscan Belt. Such proposed equivalence is based on lithostratigraphic, tectono-metamorphic, geochronological, and geochemical affinities between these two domains, and implies that both zones had the same Neoproterozoic and early Palaeozoic basins, recording the same magmatic episodes and enduring the same tectono-metamorphic processes related to the Variscan Orogeny. As so, in order to better understand the evolution of these domains during the Ediacaran-Cambrian period, a comprehensive geochemical, isotopic and geochronological analysis of the metasediments that make up the OMZ and the allochthonous units of the GTMZ was carried out. The results show that the metasediments of OMZ and the Lower Allochthonous units of GTMZ present similar geochemical and geochronological features, having been likely deposited near each other, although small, but specific differences between both domains suggest that they do not correspond to the same depocentre. However, no geochemical, isotopic or geochronological correlation can be established with any of these domains and the Upper Allochthonous units of GTMZ. These metasediments display quite exotic features and, as such, were likely deposited in a different narrower basin, located to the W of the basins where OMZ and Lower Allochthonous units of GTMZ were deposited, thus providing precise constraints on the paleogeographic reconstruction of these domains during the Neoproterozoic to Early Ordovician dismembering of Gondwana.</p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126168"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S000928192400093X/pdfft?md5=3776dc95daaec9fc9bcf16bfecb3ff10&pid=1-s2.0-S000928192400093X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochronology and petrogenesis of multiple magmatic events in the Tianbaoshan orefield, NE China: Implications for tectonic evolution","authors":"","doi":"10.1016/j.chemer.2024.126141","DOIUrl":"10.1016/j.chemer.2024.126141","url":null,"abstract":"<div><p><span><span><span>Recent studies have shown that multistage magmatic and metallogenic events in NE China were dominated by the Paleo-Asian Ocean tectonic regime and the Paleo-Pacific Ocean tectonic regime. However, outstanding questions remain on the petrogenesis<span> and fertility of ore-causative magma in each metallogenic event. In this study, we report new geochronologic and geochemical data on ore-causative intrusions from the Tianbaoshan orefield in the east Jilin-Heilongjiang belt (EJHB), aiming to identify their petrogenesis, magma fertility, and their implications for the </span></span>geodynamic evolution of the EJHB. Middle </span>Permian Lishan ore-causative quartz monzodiorites with abundant mafic microgranular enclaves (MMEs) were emplaced at ca. 264.9 ± 2.6 Ma. Petrographic and geochemical characteristics (</span>⁸⁷Sr/⁸⁶Sr_(i) = 0.7049–0.7053, ε_Nd(t) = 2.9–3.7, and ε_Hf<span><span>(t) = 4.7–11.7) indicate a juvenile crust source injected by a slab-metasomatized mantle component. The Early Jurassic<span> Beishan monzogranites (ca. 192.5 ± 1.8 Ma) were generated by the partial melting of the juvenile underplating basaltic lower crust with subsequent </span></span>fractional crystallization in response to their highly evolved geochemical features, combined with their depleted Sr-Nd-Hf isotopic signature (I</span>_Sr = 0.7032–0.7037, ε_Nd(t) = 2.8–3.3, and ε_Hf<span><span>(t) = 7.2–12.2). Based on the zircon </span>trace element geochemistry, we infer that the Middle Permian quartz monzodiorites had a high oxygen fugacity (Ce</span>⁴⁺/Ce³⁺ = 40–216), potentially generating the Pb-Zn-Cu mineralization. Early Jurassic Beishan monzogranites had a lower magmatic oxygen fugacity (Ce⁴⁺/Ce³⁺<span> = 14–106), which may account for the Mo-dominated mineralization. A combination of this study and previous results corroborates that the Tianbaoshan orefield records the superposition of different tectonic regimes during metallogenesis.</span></p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126141"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141394339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Albitization related U and Th mobilization under reducing conditions","authors":"","doi":"10.1016/j.chemer.2024.126160","DOIUrl":"10.1016/j.chemer.2024.126160","url":null,"abstract":"<div><p><span><span>Hydrothermally altered quartzofeldspathic gneisses, granites and pegmatites of the West Garo Hills, Shillong Plateau (eastern India) preserve alteration assemblages of monazite, </span>xenotime<span> and zircon<span><span> comprising thorite and coffinite in the altered domains. </span>Albitization<span><span> of muscovite and K-feldspars, sericitization of K-feldspar and albite, alteration of </span>biotite to hydrobiotite, and crystallization of tourmaline is suggestive of the involvement of acidic fluids. The microtextural relations and the mineral assemblages indicate prevalence of low-temperature (</span></span></span></span><em>T</em><span> &lt; 300 °C) conditions during hydrothermal alteration. The light δ</span>¹¹B values of tourmaline (–15.1 to –13.5 ‰) suggests derivation/interaction of the fluids from/with metapelitic rock and/or S-type granite. Low ‘inferred’ Fe³⁺/Fe²⁺<span> ratio in tourmaline (based on high Al content in Y-site, 0.16–0.56 apfu, avg. 0.36 apfu), estimated excess charge (0.22–0.47, avg. 0.35 apfu) and lack of any Fe–Al relation support a reduced nature of the hydrothermal fluid. Mass balance calculations reveal that Th and U required for the formation of thorite and coffinite, respectively were likely derived from monazite and xenotime, and zircon. Significantly lower Cl</span>^─ contents in hydrobiotite (avg. 0.03 wt%) compared to the unaltered biotite (avg. 0.13 wt%) suggests release of Cl^─ to the hydrothermal fluid during alteration. Textural evidences of albitization together with Cl^─ release from biotite suggest increased Cl^─ concentrations in the fluid during hydrothermal alteration. Based on solubility calculations for various U and Th species, we propose that high Cl^─ content in the fluid aided mobilization of Th and U as ThCl₄⁰ and UCl₄⁰/UO₂Cl₂⁰<span> complexes from accessory radioactive phases under reducing conditions. These results suggest that significant mobility of U and Th can be achieved in acidic high salinity fluid even under reducing conditions. Thermodynamic calculations for the solubility of Th- and U-chloride complexes and stability of monazite/xenotime in a range of pH and temperature suggest that thorite and coffinite precipitation was the result of an increase in pH.</span></p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126160"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141505971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Origin and thermal evolution of Cr-V-Ti magnetites (lodestones) from Coorg massif, southern India","authors":"","doi":"10.1016/j.chemer.2024.126142","DOIUrl":"10.1016/j.chemer.2024.126142","url":null,"abstract":"<div><p><span><span><span><span>This study deals with petrology<span>, textural, thermometry, and geochemical characterization of naturally magnetized Cr-V-Ti magnetite deposits within the layered mafic-ultramafic intrusions in Coorg massif of southern India using ore petrography and mineral/whole rock geochemistry. These deposits, also known as ‘lodestones’, occur as rhythmic layers within the lateritized host rock, with the underlying basement distinguished by the presence of </span></span>charnockites<span><span> and layered gabbro-anorthosites and pyroxenites<span>, delineating a stratified intrusive setting. Lodestones exhibit complex mineral assemblage involving magnetite, ilmenite, ulvöspinel, spinel, corundum, hematite, </span></span>goethite, pyrite, </span></span>pyrrhotite<span>, and amphiboles. The bulk rock chemistry of the lodestone is analogues to Fe-Ti magnetite </span></span>iron ore<span> deposits with elevated vanadium and chromium contents. Their resemblance to tholeiitic magma-type suggests their formation in a layered intrusive setting, evolved through multiple fractional crystallization under oxidizing conditions. Thermometric and fugacity calculations using different textural associations estimate the magmatic fractional crystallization stage at elevated temperatures (601–704 °C) and low </span></span><em>f</em>O₂<span> (−18.6 to −15.3), succeeded by the exsolution stage during subsolidus cooling at lower temperatures (379–540 °C) and high </span><em>f</em>O₂<span> (−38.2 to −22.1). The whole sequence of formation and evolution of lodestone encompasses primary magmatic crystallization, subsolidus re-equilibration, metamorphism, and secondary weathering. The study also suggests a genetic linkage of lodestone with the associated mafic-ultramafic units, depicting two possible magmatic processes either through slab melting and fractional crystallization associated with subduction or due to plume magmatism and associated rifting.</span></p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126142"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compositional signatures of clinopyroxenes from the mafic rocks of the Nagaland ophiolite (NE India): Inferences for melting of diverse source regions in a transitional arc-type setting","authors":"","doi":"10.1016/j.chemer.2024.126150","DOIUrl":"10.1016/j.chemer.2024.126150","url":null,"abstract":"<div><p><span>The Nagaland-Manipur ophiolite<span><span> belt (NMOB) represents remnants of the Neo-Tethyan Ocean that evolved during the accretion of the Indian and Myanmar lithospheric plates. We studied clinopyroxenes of cumulate gabbro and </span>basalt<span> rocks from the northern section of the belt to decode the mechanism that controlled their petrogenesis and geotectonic setting. Clinopyroxenes (augite-diopside) exhibit compositional zoning and significant variations in their major and trace element contents. Zoned clinopyroxene from a single volcanic rock sample (2d-3-6-11) show higher concentrations of TiO</span></span></span>₂<span> (1.44 to 5.13 wt%) and Al (0.128–0.359 apfu) and lower Si (1.658–1.889 apfu) compared to clinopyroxenes from the other mafic rocks. The mg# [100 × Mg/(Mg + Fe</span>²⁺<span>)] values of clinopyroxenes range between 60.1 and 85.7. The trace element contents and the chondrite-normalised REE<span><span> patterns of clinopyroxenes imply diverse geochemical affinities of both depleted mantle typical of tholeiite rocks and a less depleted LREE-enriched melt for the Nagaland mafic rocks. Pressure and temperature of crystallisation were estimated using single clinopyroxene geothermobarometry and were found to vary between 1–8 kbar and 840–1179 °C, respectively. In discrimination diagrams, the zoned clinopyroxenes show an alkaline composition consistent with a within-plate environment. On the other hand, clinopyroxenes from the rest of the mafic samples show a sub-alkaline composition typical of </span>magmas produced in arc-related settings. Our study indicates the existence of diverse magma sources in an island arc-to-back arc setting during the formation of magmatic rocks in the NMOB.</span></span></p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126150"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141402531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implications of Late Triassic–Middle Jurassic detrital zircons from the southeastern margin of the South China Block for the Paleo-Pacific Plate subduction","authors":"","doi":"10.1016/j.chemer.2024.126152","DOIUrl":"10.1016/j.chemer.2024.126152","url":null,"abstract":"<div><p><span>There existed an early Mesozoic tectonic regime transformation in the South China Block (SCB). Although it was believed that this transformation was closely related to the subduction of Paleo-Pacific Plate, the process and initial time of the subduction of the Paleo-Pacific Plate have been controversial for a long time. Based on the published Upper Triassic and Middle Jurassic<span><span> succession detrital zircons </span>geochronology<span> from the southeastern margin of the SCB, the newly obtained Late Triassic to Middle Jurassic detrital zircons Hf isotope data, and the available magmatic age data and Hf isotope data, this study discussed the subduction of the Paleo-Pacific Plate. The Hf isotope composition of zircon grains selected from the Early Mesozoic strata of the SCB, spanning from the Late Triassic to the Middle Jurassic, exhibits a consistent temporal trend with that of the Triassic–Middle Jurassic magmatic rocks. Both display a transition from negative to positive ε</span></span></span>_Hf<span>(t) values, indicative of a gradually increasing contribution of mantle-derived materials from the Triassic to the Middle Jurassic. Zircon trace elements indicate that a magmatic arc appeared outside the southeastern margin of the SCB at 200–190 Ma and continued to develop into the Middle Jurassic, which may have been generated by the Paleo-Pacific Plate subduction. This study proposed that the Paleo-Pacific Plate subduction was confined to the southeastern coast of the SCB in the Late Triassic, and the subduction of the flat slab was halted by obstruction at the end of the Late Triassic. In the Early Jurassic, the Paleo-Pacific Plate began to subduction again, and arc-related magmatic rocks were formed along the coast of SCB. At the same time, due to the remote effect of the subduction of the Paleo-Pacific Plate, the weak tectonic belt existing in the Nanling area was reactivated, resulting in the Nanling area in the intraplate extensional setting. Subsequently, the continuous subduction of the Paleo-Pacific Plate led to the thickening of the crust along the SCB in the Middle Jurassic, and the Nanling area was still under in the extensional setting.</span></p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126152"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141513072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenesis of the Neoarchean (2.7 Ga) Poularies intrusion: Geochemical evolution of a shallow syn-volcanic granitoid complex from the Abitibi granite-greenstone belt, Québec","authors":"","doi":"10.1016/j.chemer.2024.126164","DOIUrl":"10.1016/j.chemer.2024.126164","url":null,"abstract":"<div><p><span><span><span>The Poularies igneous complex is a Neoarchean (2728 Ma) intrusion composed of diorite<span>, quartz diorite, hornblende tonalite, and </span></span>biotite tonalite. It is was emplaced into the shallow crust of the Abitibi granite-greenstone belt during volcanic cycle 1 (2730–2725 Ma) and is contemporaneous with the eruption of mafic (Stoughton-Roquemaure Group) and silicic volcanic rocks (Hunter Mine Group). The petrogenetic relationship between the silicic rocks of the Poularies igneous complex is not constrained. In this study we test the petrological association between the different rock types of the Poularies complex using </span>fractional crystallization modeling. Hydrous (H</span>₂<span><span><span>O = 3 wt%) fractional crystallization modeling using a ‘primitive’ intermediate starting composition demonstrates that all rock types of the Poularies complex can be generated from a common parental magma in the </span>upper crust (1 kbar) under mildly oxidizing conditions (ΔFMQ = 0). Moreover, it is demonstrated that the parental magma of the Poularies complex was likely derived by partial melting of </span>mafic rocks<span> from the Abitibi granite-greenstone belt. We conclude that the Poularies complex is representative of a magma chamber that generated the silicic lavas of the spatially associated Hunter Mine Group in a rifting or tensional plate stress environment. Our model may be applicable to other shallow </span></span><em>syn</em>-volcanic plutons of the Abitibi granite-greenstone belt.</p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126164"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141569355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Contrasting fluids and implications for ore genesis in the Jiawula-Chaganbulagen Porphyry Mo-epithermal PbZn metallogenetic system: Evidence from fluid inclusions and H-O-He-Ar isotopes","authors":"","doi":"10.1016/j.chemer.2024.126110","DOIUrl":"10.1016/j.chemer.2024.126110","url":null,"abstract":"<div><p>The Jiawula-Chaganbulagen (Jia-Cha) ore field is located in the part of the southern Erguna Block of Northeast China and has significant mineralization potential. It comprises three deposits: The Chaganbulagen hydrothermal vein-type Pb<img>Zn (Ag) deposit in the southeast, the Jiawula hydrothermal vein-type Pb<img><span>Zn (Ag) deposit in the northwest, and the blind porphyry Mo mineralization in between. Previous geochronological dates, including molybdenite Re</span><img><span>Os, zircon U</span><img>Pb, sulfide Rb<img>Sr, and sericite Ar<img>Ar, indicate that the formation of hydrothermal molybdenite and the Pb<img><span><span>Zn mineralization were coeval and that they originated from a porphyry-epithermal metallogenetic system that was related to Early Cretaceous </span>magmatism<span>. However, our comprehensive analysis of fluid inclusions and H-O-He-Ar isotopes reveals dissimilarities in the features and sources of the fluids that form three different deposits. Both the Jiawula deposit and porphyry Mo mineralization have three distinct types of fluid inclusions, which comprise liquid-rich two-phase aqueous inclusions (L-type), vapor-rich two-phase inclusions (V-type), and daughter mineral-bearing three-phase inclusions (S-type). The He</span></span><img>Ar (³He/⁴He = 1.32–1.51 Ra; ⁴⁰Ar/³⁶Ar = 300 to 324) and H<img>O (δ¹⁸O_{H2O =} − 13.4 ‰ to 4.1 ‰; δD₌ − 155.1 ‰ to −129.9 ‰) isotope analysis results suggest that the trap fluids originated from an H₂<span>O-NaCl magmatic fluid system, which experienced Mo mineralization with high-temperature transformed into medium-temperature fluids that were primarily of meteoric water in the late-stage (Jiawula Pb</span><img>Zn (Ag) deposit). The Chaganbulagen Pb<img><span>Zn (Ag) deposit features L-type and V-type inclusions, along with aqueous‑carbonic inclusions (C-type). The results of Laser Raman analysis reveal that the gas phases of the fluid inclusions present in Chaganbulagen contain three different compositions: H</span>₂O, CO_2, and CH₄. The H<img>O isotope compositions (δ¹⁸O_H2O = −18.8 ‰ to −11.6 ‰; δD = −166 ‰ to −131 ‰) and He<img>Ar (³He/⁴He = 0.034–0.041 Ra; ⁴⁰Ar/³⁶Ar = 296–298) in quartz of the Chaganbulagen Pb<img><span>Zn (Ag) deposit indicate that the crustal fluids (MASW) were the main source of the ore-forming fluids, and belonged to a H</span>₂O-NaCl-CO₂-CH₄ system, which had low-temperature and low-salinity characteristics. By combining previously published geochronological dates, we proposed a model to explain the difference in the evolution of the fluids.</p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126110"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140268757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ediacaran anorogenic alkaline magmatism and wolframite mineralization linked to mantle plume activity in the north Arabian-Nubian Shield (Egypt)","authors":"","doi":"10.1016/j.chemer.2024.126119","DOIUrl":"10.1016/j.chemer.2024.126119","url":null,"abstract":"<div><p><span>The termination of the collision between West and East Gondwana<span><span> and the Pan-African orogeny is somewhat regarded as an endorsement for the generation and intrusion of alkaline magmatism in the Arabian-Nubian Shield. However, the current ages of the Abu Hamar-Abu Kharif alkaline granites have changed this endorsing connection. The Gebel Abu Hamr and Gebel Abu Kharif plutons, exposed in the northern Egyptian Eastern Desert, are anorogenic rift-related granite (A-type) and possess characteristics indicative of a within-plate </span>tectonic setting. Their U</span></span><img><span>Pb ages (616.6 ± 6.4 and 614.6 ± 3.6 Ma) are remarkable and provide insight into the initial phase of the anorogenic alkaline magmatism within the shield. The zircon U</span><img><span><span>Pb dating, geochemical data, and zircon geochemistry<span><span> together suggest that the primary magma was formed by the upwelling of a short-lived </span>mantle plume. These alkaline granites subsequently intruded into the crustal mesozone at a thickness of 20–30 km with average temperatures of ~680 °C. The structural framework of the studied plutons reveals a noticeable correlation between their emplacement and the Najd left-lateral fault system. These alkaline granite plutons host wolframite-bearing </span></span>quartz veins. The in-situ U</span><img><span>Pb dating of wolframite<span> yielded a weighted mean age of 603.7 ± 7.4 Ma. The trace and rare earth elements of wolframite, zircon, and the hosting alkaline granites share significant geochemical similarities. Nevertheless, the proximity of the U</span></span><img>Pb age of wolframite and the associated granites suggests an epigenetic origin.</p></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126119"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140610378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Soil CO2 fluxes measured in the Acoculco Geothermal System, Mexico: Baseline emissions from a long-term prospection programme” [Geochem. In Press, Corrected Proof]","authors":"","doi":"10.1016/j.chemer.2024.126151","DOIUrl":"10.1016/j.chemer.2024.126151","url":null,"abstract":"","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 3","pages":"Article 126151"},"PeriodicalIF":2.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S000928192400076X/pdfft?md5=830cddcf6ecdc4e74d5cc8f40dcc1d11&pid=1-s2.0-S000928192400076X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141408104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}