Precambrian Research最新文献

{"title":"Carbonatite and syenite magmatism at the Archean-Proterozoic boundary in the Western Dharwar Craton, Southern India: Implication for petrogenesis, source characteristics and terrane geodynamics","authors":"Samir Debnath ,&nbsp;Rohit Pandey ,&nbsp;B. Belyatsky ,&nbsp;David Chew ,&nbsp;N.V. Chalapathi Rao ,&nbsp;Mahendra Kumar Singh","doi":"10.1016/j.precamres.2025.107995","DOIUrl":"10.1016/j.precamres.2025.107995","url":null,"abstract":"<div><div>A comprehensive study integrating field data, geochronology, mineral-whole rock geochemistry, and Sr-Nd-Pb-C-O isotope systematics is presented for a newly identified carbonatite-syenite complex from Gundlupete area, near the tectonic boundary between the Western Dharwar Craton and the Granulite Terrain, South India. The syenite, composed of alkali feldspar, albite, clinopyroxene, and biotite, yields a U-Pb titanite crystallisation age of 2590 ± 42 Ma. It displays shoshonitic geochemistry, with enriched LILE-LREE, depletion in Mg, Ni, Cr, HFSEs, and crust-like Th/Nb and Nb/U ratios. Initial εNd values (–1.4 to +1.0) and Nd model ages of 2.8–3.0 Ga indicate derivation from partial melts of Mesoarchean TTG crust, modified by fractional crystallisation. The intrusive carbonatite with a monazite U-Pb age of 2474 ± 27 Ma, is dominated by calcite, apatite, magnetite, monazite, amphibole, and phlogopite, and is enriched in Sr, REEs, and LILEs. Field and petrographic observations reveal distinctive apatite-magnetite-silicate banding within the carbonatite near the syenite contact, a feature inconsistent with simple magmatic differentiation. Instead, metasomatic reactions at the carbonatite-syenite interface likely produced antiskarn assemblages through wall-rock silica contamination. Sr-Nd-Pb isotope data shows time integrated higher Rb-Sr but low Sm/Nd and U/Pb ratios, tapping a chondritic to slightly enriched lithospheric mantle source modified by incorporation of small fractions of ancient subducted sediments into the source region. C–O isotope data show mantle-like δ¹⁸O, and the uniformly low δ¹³C (–10.23 to –9.41 ‰) further points to an organic component in the subducted sediments. Syenite and carbonatite magmatism relates to the Neoarchean amalgamation of the Dharwar Craton and Granulite Terrain, driven by northward subduction of the Dharwar ocean lithosphere. The syenite emplacement at 2.59 Ga is linked to the regional subduction-related magma underplating and crustal anatexis, while carbonatite intrusion at 2.47 Ga suggests a post-collisional magmatic pulse during terminal accretion near the Archean-Proterozoic boundary. The temporal, geochemical, and isotopic evolution recorded in the Gundlupete complex thus provides a robust archive of subduction-driven carbon recycling, mantle metasomatism, and crustal reworking processes at the Archean-Proterozoic transition.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"433 ","pages":"Article 107995"},"PeriodicalIF":3.2,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magma source and tectonic setting of gabbronorite–anorthosite massifs: geochemical and isotopic evidence from the 1.5 Ga Sejny Intrusion (Mazury Complex, NE Poland)","authors":"Anna Grabarczyk-Gurba ,&nbsp;Ewa Krzemińska ,&nbsp;Leonid Shumlyanskyy ,&nbsp;Janina Wiszniewska","doi":"10.1016/j.precamres.2025.107942","DOIUrl":"10.1016/j.precamres.2025.107942","url":null,"abstract":"<div><div>The Sejny Intrusion, a part of the anorthosite–mangerite–charnockite–granite (AMCG) Mazury Complex in NE Poland, comprises mafic to intermediate rocks, including gabbro, (gabbro)norite, anorthosite, and jotunite dykes. Zircon U–Pb ages of 1513 ± 2 Ma to 1499 ± 3 Ma define its emplacement. The primitive jotunites, with relatively high SiO₂ and low Fe-Ti-P contents, display chilled margins, reflecting a composition close to the parental magma. Their REE patterns and isotopic signatures (ε_Nd(t) of −1.6 to −1.8, ⁸⁷Sr/⁸⁶Sr_(i) of 0.7040−0.7044, and maximum single ε_Hf(t) of 2.3 (mean = −2.5)) are consistent with a lower crustal source. Fractionation of plagioclase and minor Ca-poor pyroxene from jotunitic melts occurred at ca. 35 km depth and is evidenced by orthopyroxene with exsolved plagioclase lamellae, originally forming high-Al orthopyroxene megacrysts (HAOMs; 5.9–6.7 wt% Al₂O₃), typical of high-pressure crystallization. Plagioclase-rich (anorthositic) and gabbro-noritic mushes were then emplaced within the shallow crust. Evolved jotunites, enriched in Fe-Ti-P and depleted in SiO₂, represent residual melts after fractionation of the anorthosite-gabbronorite suite. Anorthosites and gabbros (ε_Nd(t) of −1.4 to −2.0, ⁸⁷Sr/⁸⁶Sr_(i) of 0.7041−0.7049, mean ε_Hf(t) of −2.2 to −3.6) isotopically overlap with primitive jotunites. Conversely, evolved quartz jotunite (ε_Nd(t) = −2.4, ⁸⁷Sr/⁸⁶Sr_(i) = 0.7053, mean ε_Hf(t) = −4.1), quartz gabbronorite (ε_Nd(t) = −2.5, ⁸⁷Sr/⁸⁶Sr_(i) = 0.7043), and quartz norite (ε_Nd(t) = −2.7, ⁸⁷Sr/⁸⁶Sr_(i) = 0.7072, mean ε_Hf(t) = −5.5 and −7.5) exhibit a gradual decrease in ε_Nd and ε_Hf, and mostly higher ⁸⁷Sr/⁸⁶Sr values. This is consistent with zircon O−Hf trends for quartz jotunite and quartz norite (δ¹⁸O = 6.8−10.2 ‰, ε_Hf(t) = −0.4 to −10.1), reflecting interaction between a low δ¹⁸O, high ε_Hf (∼0) ‘juvenile’ source, and a supracrustal component of high δ¹⁸O and low ε_Hf values. The decrease in zircon ε_Hf(t) with decreasing age indicates progressive contamination during ascent. Inherited 1825 ± 4 Ma zircons in one sample corroborate the influence of Paleoproterozoic metasedimentary wall-rock during emplacement. Based on coeval relationship with A-type granitoids, the Sejny Intrusion is interpreted as anorogenic. This magmatism likely resulted from asthenospheric upwelling beneath the Columbia supercontinent, where heat accumulation (thermal blanket effect) induced partial melting of the lower mafic crust.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107942"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145521186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resolving the syn-genetic mineralization age of a metamorphosed Archean VHMS deposit using multiple geochronological approaches","authors":"Cendi D.P. Dana ,&nbsp;Steven P. Hollis ,&nbsp;Lorenzo Tavazzani ,&nbsp;Cyril Chelle-Michou ,&nbsp;Stijn Glorie ,&nbsp;Yusuke Kuwahara ,&nbsp;Kazuhide Mimura ,&nbsp;Moei Yano ,&nbsp;Junichiro Ohta ,&nbsp;David Selby ,&nbsp;Yasuhiro Kato ,&nbsp;Vanessa Pashley ,&nbsp;Megan James ,&nbsp;Darryl Podmore","doi":"10.1016/j.precamres.2025.107968","DOIUrl":"10.1016/j.precamres.2025.107968","url":null,"abstract":"<div><div>Accurately determining the timing of mineralization is essential for exploring <em>syn</em>-genetic stratiform mineral systems, such as volcanic-hosted massive sulfide (VHMS) deposits. This study integrates multiple geochronological techniques to constrain both the age of <em>syn</em>-genetic mineralization and subsequent overprinting magmatic, metamorphic and deformation events at the King VHMS deposit, Western Australia. The timing of <em>syn</em>-genetic mineralization is collectively constrained by consistent ages from U–Pb zircon geochronology of host felsic volcanic rocks (2725 ± 10 Ma), a Re–Os pyrite isochron (2730 ± 26 Ma), and Pb–Pb galena model ages (ca. 2714–2718 Ma). Pyrrhotite, formed via metamorphic desulfidation of pyrite, records a younger Re–Os age of 2652 ± 32 Ma, overlapping with the timing of prograde metamorphism dated by <em>in situ</em> Lu–Hf garnet analysis at 2680 ± 28 Ma. A Re–Os age from massive sulfide ore (2664 ± 23 Ma), reflecting a mixture of pyrite and pyrrhotite, produces a geologically meaningless average due to metamorphic re-equilibration, highlighting limitations of bulk Re–Os dating in high-grade metamorphosed systems. Quartz monzonite intrusions that crosscut the deposit and are associated with the regional M2 metamorphism yielded weighted mean U–Pb zircon ages of ca. 2676–2665 Ma, and are associated with minor molybdenite mineralization (Re–Os ages ca. 2650–2655 Ma). Collectively, these results confirm that the King Zn deposit represents the first phase of VHMS mineralization during the formation of the Kalgoorlie-Kurnalpi Rift (KKR), and significantly predates other VHMS deposits of the Eastern Goldfields. This study also demonstrates that the Re–Os isotopic signature of <em>syn</em>-genetic pyrite can be retained through amphibolite-facies metamorphism, providing a new opportunity to directly date VHMS deposits affected by high-grade metamorphism in Archean cratons globally. In contrast, Re–Os ages of pyrrhotite record prograde metamorphism, offering a potential tool for constraining metal remobilization events.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107968"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145521185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 “Growth and disparity of form in the Ediacaran genus Charnia, with description of Charnia brasieri sp. nov. from the Ediacaran of Avalonia”. [Precambrian Res. (2025) 107947]","authors":"D. McIlroy,&nbsp;D. Pérez-Pinedo,&nbsp;S. Rosse-Guillevic,&nbsp;H. Muirhead-Hunt,&nbsp;R.S. Taylor,&nbsp;S.C. Dufour","doi":"10.1016/j.precamres.2025.107976","DOIUrl":"10.1016/j.precamres.2025.107976","url":null,"abstract":"","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107976"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145736754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraining crustal-level granite emplacement through thermobarometry and gravity modelling: Insights from the Ediacaran Acari Batholith, Borborema Province, NE Brazil","authors":"Christian C.B. Rocha ,&nbsp;Rafael G. Motta ,&nbsp;Nitzschia R.R. Domingos ,&nbsp;Frederico C.J. Vilalva ,&nbsp;Rogério Cavalcante ,&nbsp;Dinarte Lucas","doi":"10.1016/j.precamres.2025.107977","DOIUrl":"10.1016/j.precamres.2025.107977","url":null,"abstract":"<div><div>The Acari Batholith is a syntectonic Ediacaran (∼575 Ma) intrusion emplaced in the Seridó Belt, northeastern Brazil, during the Brasiliano Orogeny, a major tectonic event associated with the assembly of West Gondwana. It represents the largest granitic body within the belt. While the exposed geology of the Acari Batholith is well characterized, its subsurface geometry remains poorly constrained. To address this, we performed 2.5D forward gravity modelling to investigate its architecture and integrated the results with existing AMS, thermobarometric, borehole, and regional data. The modelling results represent one plausible subsurface configuration that is consistent with the gravity data and available geological constraints. They reveal an eastward-shifted feeder zone with two NE-SW aligned roots. The model suggests a predominantly shallow body, with a low-angle floor. A thin mica schist layer overlies the northern root and separates the Acari Batholith from the Acauã Stock, a satellite body that belongs to the same magmatic system. Thermobarometric estimates based on the normative quartz–orthoclase–albite geobarometer yield crystallization pressures of 2.6–3.5 kbar, consistent with the HT/LP metamorphism in the Seridó Belt. Synchronicity between magma emplacement and Brasiliano deformation is inferred from the alignment of internal magmatic fabrics with regional structures, while a mylonitic zone along its western margin developed after solidification. Cordierite + sillimanite assemblages in adjacent mica schist further attest to high temperatures near the roots. Combined with regional data, these results support the interpretation that the Acari Batholith represents a magmatic expression of the migmatitic dome system formed during Brasiliano transpression.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107977"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145618078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reply to Comment on “Revealing the early geological history of the Istanbul Zone (Far-East Avalonia) through zircon U-Pb-Hf isotopic data”","authors":"Sinan Yılmazer ,&nbsp;Gültekin Topuz ,&nbsp;Marcel Guillong ,&nbsp;Aral I. Okay ,&nbsp;İnal Demirkaya ,&nbsp;Fulya Uzun","doi":"10.1016/j.precamres.2025.107963","DOIUrl":"10.1016/j.precamres.2025.107963","url":null,"abstract":"","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107963"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145521183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-resolution U-Pb dating of the Croles Hill Diamictite, Tasmania: Near-synchroneity of widely separated mid-Ediacaran glacial deposits","authors":"C.R. Calver ,&nbsp;G.V. Cumming ,&nbsp;G.P. Halverson ,&nbsp;J.L. Crowley ,&nbsp;N.J. Roberts ,&nbsp;M. Schmitz","doi":"10.1016/j.precamres.2025.107958","DOIUrl":"10.1016/j.precamres.2025.107958","url":null,"abstract":"<div><div>Ediacaran glacial deposits are widespread, but their distribution in space and time is still poorly understood, hindering global correlation and a better understanding of their association with environmental and biological change. Of these deposits, the Gaskiers Formation and nearby Trinity Diamictite in eastern Newfoundland are the best constrained radiometrically at ca. 579––581 Ma, although recent evidence suggests glaciation initiated several million years earlier. Here we report two new U-Pb (zircon) CA-ID-TIMS dates on rhyodacite units immediately below, and within the Croles Hill Diamictite in northwest Tasmania previously interpreted as glacial in origin: 579.20 ± 0.09 Ma and 578.86 ± 0.23 Ma respectively. These ages make the Croles Hill Diamictite slightly younger than the Gaskiers Formation (&gt;579.88 ± 0.44 Ma) but permit correlation with the Trinity Diamictite. Deposition of all three diamictites took place in a narrow (&lt;2.7 m.y.) temporal window. Features consistent with a glacial origin for the Croles Hill Diamictite include rare, laminated mudstones with dropstones, a single, consistent stratigraphic position within the Togari Group, and compositional diversity of clasts.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107958"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145521187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Zircon U-Pb ages and Lu-Hf isotopic systematics in granites from Mt Isa Inlier − evidence of prolonged reworking of an active continental margin during the final assembly of the Nuna (Columbia) supercontinent","authors":"Sutthida Noptalung,&nbsp;Ioan V. Sanislav,&nbsp;Helen A. Cocker,&nbsp;Avish Kumar","doi":"10.1016/j.precamres.2025.107965","DOIUrl":"10.1016/j.precamres.2025.107965","url":null,"abstract":"<div><div>The Mount Isa Inlier, located along the eastern margin of the North Australia Craton (NAC) preserves a long history of intrusive activity linked to the assembly of the Nuna supercontinent. The intrusive rocks in the Inlier formed during six igneous events between ca. 1880 and 1490 Ma. Intrusive rocks in the south-western part of the Inlier (Dajarra region) were previously assigned ages of ca. 1680–1650 Ma without direct U-Pb geochronological constraints. New U-Pb zircon ages from granitic rocks in the Dajarra region reveal intrusive events at ca. 1860 Ma, ca. 1820–1780 Ma, ca. 1710–1690 Ma, and ca. 1670–1650 Ma corresponding to the Kalkadoon, Argylla, Wonga-Burstall and Sybella Igneous Events, respectively. These results indicate that these granites are much older than previously thought and have important implications for intrusive relationships and stratigraphic correlations. Zircon Hf isotopic compositions show negative ɛHf_(t) values (+0.0 to −5.5) at ca. 1860 Ma, mixed values (−5.3 to + 8.4) at ca. 1820–1780 Ma, and unradiogenic signatures at ca. 1710–1690 Ma (−8.1 to −0.1) and ca. 1650 Ma (−5.1 to −4.3). These isotopic data indicate that the magmas were generated predominantly by internal reworking of older crust with limited juvenile input. The magmatic belts corresponding to the Kalkadoon and Argylla Igneous Events can be correlated with coeval igneous events in the NAC and the South Australia Craton (SAC) and may have formed in response to a northerly dipping subduction system located along the southern margin of the NAC. The Wonga-Burstall and the Sybella Igneous Events may have formed in response to a westward dipping subduction system developed along the eastern margin of the NAC during the final stages of Nuna assembly. The new geochronological and isotopic data presented here fill in an important gap in the magmatic history of the Mount Isa Inlier and contributes towards a more comprehensive understanding of tectonic activity along the eastern margin of the NAC and the final assembly of the Nuna supercontinent.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107965"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145479141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrochronology and genesis of granite-hosted rare metal (Ta, Nb, Li, Y + REE, Zr)-F-bearing mineral occurrences in the Cameroon Northern Domain of the Central African Orogenic Belt","authors":"Thierry Bineli Betsi ,&nbsp;Eric Joseph Njee ,&nbsp;Louise Marie Ngo Bidjeck Bondje ,&nbsp;Eugene Pascal Binam Mandeng ,&nbsp;Kirsten Drüppel ,&nbsp;Aratz Beranoaguirre ,&nbsp;Hubert Mvondo ,&nbsp;Tebogo Kelepile ,&nbsp;Elisabeth Eiche ,&nbsp;Jochen Kolb ,&nbsp;Charles Nkoumbou","doi":"10.1016/j.precamres.2025.107966","DOIUrl":"10.1016/j.precamres.2025.107966","url":null,"abstract":"<div><div>The Ngoutchoumi Granite Complex in the Cameroonian Northern Domain (ND) of the Neoproterozoic Central African Orogenic Belt has long been known to host tungsten mineral occurrences. Here, we show that this granite complex also contains a suite of rare metals (Ta, Nb, Zr, Li, Y + REE) and F-bearing minerals, which have not been previously reported. The key genetic aspects pertaining to the genesis of this mineralised system are unconstrained. In this study, that couples <em>in-situ</em> LA-ICP-MS zircon and columbite U-Pb and mica<!--> ⁴⁰Ar-³⁹Ar geochronology with bulk-rock and mineral geochemistry and Raman spectroscopy, the rare metal minerals and their host granite are characterized. The granite is peraluminous and rich in REE (100–445 ppm), with strong LREE enrichment ((La/Yb)_N<!-->= 2.38–41.4) and typically displays a pronounced negative Eu anomaly (Eu/Eu* = 0.06–0.10). Rare metal minerals, including ferrocolumbite, Nb-rich rutile, zircon and various REE minerals are intimately associated with fluorite. Zircon and ferrocolumbite from the rare metal-rich granite yield Pan-African ages of 639 ± 11 Ma and 640.2 ± 12.7 Ma, respectively, indicating part of the rare metal minerals is orthomagmatic. Textural and mineral chemistry features indicate that the primary orthomagmatic rare metal minerals were overprinted, thus leading to at least three episodes of rare metal mineralisation. On the other hand, biotite and muscovite from granite crosscutting the rare metal granite yield Ar-Ar plateau ages of 549.02 ± 0.85 and 552.17 ± 0.22 Ma, respectively, which, when combined with our ferrocolumbite age, as well as previously reported rare metal-related ages within the ND, bracket the age of rare metal mineralisation events within the ND, between ca.640–580 Ma. Our findings, therefore, extend both the spatial and temporal fingerprints of the ND rare metal mineralisation beyond those previously reported and have significant implications for the exploration of rare metals in Pan-African terranes. The episodes of formation of rare metals at Ngoutchoumi span from the orthomagmatic stage to the hydrothermal stage, and this genetic model sheds new light on the genesis of rare metal granite-type deposits, where debates have revolved around metasomatic vs. magmatic rare metal enrichment processes.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107966"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145579883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Locating Tarim on the periphery of the Columbia supercontinent: New evidence from Mesoproterozoic amphibolites from the Central Tianshan block","authors":"Jinyu Xi ,&nbsp;Xiaoran Zhang ,&nbsp;Shuiyue Xue ,&nbsp;Guochun Zhao","doi":"10.1016/j.precamres.2025.107967","DOIUrl":"10.1016/j.precamres.2025.107967","url":null,"abstract":"<div><div>The Columbia supercontinent is considered as the oldest widely-accepted supercontinent on Earth, but its precise paleogeographic reconstruction, particularly the specific locations of peripheral continents (e.g., the Tarim Craton), still remains contentious due to the lack of key geological evidence. Here, we report new whole-rock major- and trace-elemental, Sr-Nd isotopic, and zircon U-Pb-Hf isotopic data of Mesoproterozoic amphibolites newly found in the Central Tianshan (CTS) block along the northern margin of the Tarim Craton. LA-ICP-MS U-Pb dating on magmatic-type zircons yielded weighted mean ²⁰⁷Pb/²⁰⁶Pb ages of ca. 1405–1393 Ma, interpreted as the crystallization ages of parental magma of the amphibolites. The amphibolites are characterized by relatively low contents of SiO₂ (46.2–50.5 wt%) and total alkalis, but relatively high contents of MgO (7.0–12.9 wt%), Fe₂O_3T, and Nb (23.4–42.7 ppm). The rocks show typical ocean island basalt (OIB) signatures, such as enrichments in light rare earth and large ion lithophile elements, without negative Nb, Ta, and Ti anomalies. In addition, they exhibit positive whole-rock ε_Nd(t) values of +1.4 to +5.8 and zircon ε_Hf(t) values of −1.7 to +12.7 (mostly &gt;+2.1), suggesting derivation from an OIB-like, asthenospheric mantle source. Considering the occurrences of ca. 1458–1405 Ma subduction-related granitoids in the region, our new data establish a tectonic transition from oceanic subduction to slab rollback-related intracontinental extension at ca. 1400 Ma along the northern margin of the Tarim Craton. Combined with previous investigations, we suggest that the Tarim Craton (or northern Tarim) was most probably connected to Siberia on the periphery of the Columbia supercontinent, with its northern margin (i.e., the CTS block) facing an oceanic subduction in the Mesoproterozoic.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"432 ","pages":"Article 107967"},"PeriodicalIF":3.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145521184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}