Earth and Planetary Science Letters最新文献

{"title":"The contribution of continental volcanic arcs to global weathering fluxes: Insights from the Southern Andes","authors":"Amanda Peña-Echeverría ,&nbsp;Daniele Tardani ,&nbsp;Pascale Louvat ,&nbsp;Gerdhard L. Jessen ,&nbsp;Alida Perez-Fodich","doi":"10.1016/j.epsl.2025.119640","DOIUrl":"10.1016/j.epsl.2025.119640","url":null,"abstract":"<div><div>Rivers draining volcanic regions are key to the global flux of solutes towards the ocean and in the consumption of atmospheric CO₂ through silicate rock weathering. In active volcanic regions, degassing and hydrothermal inputs can be an additional supply to weathering fluxes from high-temperature water-gas-rock reactions. Multiple surface hydrothermal manifestations and substantial degassing characterize continental volcanic arcs, and their contribution to the silicate rock weathering budget has been overlooked in comparison with volcanic islands. Here we use as a model the Southern Andes for investigating weathering of continental volcanic arcs. The Southern Andes is one of the most globally active volcanic provinces with &gt;200 hydrothermal manifestations, high rainfall &gt; 2000 mm/yr, numerous catchments feeding larger rivers draining toward the Pacific Ocean, and predominantly mafic volcanic rocks. We sampled twenty-two rivers and sixteen hot springs at high and low discharges from different volcanic watersheds in the Southern Andes. We found that more than half of the rivers were influenced by hydrothermal inputs using hydrothermal tracers Ge/Si and δ¹¹B independently, with both tracers agreeing in most cases. Furthermore, using the chloride budget and Ge/Si ratios as high-T° weathering tracers we estimate that influence of hydrothermal activity on the dissolved silicate load ranges from 0.2 to 81 % with a mean of 11 %. As a result, we present a first estimation of chemical weathering fluxes in the Southern Andes, with silicate weathering export rates ranging from 33 to 386 ton/km²/yr across the studied catchments. Using the silicate export rates, we calculate that the total carbon consumption via weathering of the total Southern Andes area is 0.11 × 10¹² mol/yr. This figure is equivalent to 0.0013 Pg C/yr which amounts to around 1 % of the global carbon consumption by the weathering of silicate rocks on the continents. This study is the first assessment of chemical fluxes in rivers of the Southern Andes and underscores the importance of studying large-scale continental volcanic arcs to improve our understanding of the feedback of silicate rock weathering in the global carbon cycle.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119640"},"PeriodicalIF":4.8,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oligocene cooling in the North American cordillera (SW Montana, USA) revealed by dual clumped isotope thermometry","authors":"Niels Meijer ,&nbsp;Katharina Methner ,&nbsp;Nikki M. Seymour ,&nbsp;Miguel Bernecker ,&nbsp;Jens Fiebig ,&nbsp;Silke Voigt ,&nbsp;C. Page Chamberlain ,&nbsp;Andreas Mulch","doi":"10.1016/j.epsl.2025.119618","DOIUrl":"10.1016/j.epsl.2025.119618","url":null,"abstract":"<div><div>Cooling during the Eocene-Oligocene Transition (EOT; 34 Ma) and a shift towards open habitats during the end of the Oligocene (∼26 Ma) are key characteristics of the paleoclimatic history of western North America. Yet, the paleo-temperature evolution during the rest of the Oligocene remains poorly constrained. Here, we present a new temperature record from the high-elevation North American Cordillera (Sage Creek Basin; SW Montana, USA) covering 34 to 27 Ma as revealed by zircon U-Pb geochronology of four volcanic tuffs. High-precision dual clumped isotope thermometry (Δ₄₇ and Δ₄₈) is used to identify calcretes unbiased by NO₂ contaminants and kinetic effects. The Δ₄₇ values of these calcretes show no major temperature change across the EOT, but instead gradual cooling of 10 ± 1 °C during the early Oligocene (32 ± 1 to 29 ± 2 Ma). Protracted cooling after, rather than abrupt temperature changes during the EOT, may explain the lack of mammalian turnover in North American fossil assemblages compared with other continents. Reconstructed water oxygen isotope compositions remain unchanged during the early Oligocene cooling, indicating no major surface uplift at this location. Furthermore, global climate reconstructions show only a minor decrease in atmospheric CO₂ concentrations at this time. The mechanisms driving this Oligocene cooling thus remain elusive, but may be related to land surface feedbacks operating in the high-elevation North American Cordillera. Given the large magnitude of the cooling that we observe in SW Montana, these mechanisms should be considered in climate model simulations and proxy reconstructions of high-elevation regions.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119618"},"PeriodicalIF":4.8,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Massive Mg-rich fluid release across the brucite + serpentine reaction in subduction zones","authors":"Legros Emma,&nbsp;Malvoisin Benjamin,&nbsp;Brunet Fabrice,&nbsp;El Yousfi Zaccaria,&nbsp;Batanova Valentina,&nbsp;Sobolev Alexander,&nbsp;Auzende Anne-Line","doi":"10.1016/j.epsl.2025.119602","DOIUrl":"10.1016/j.epsl.2025.119602","url":null,"abstract":"<div><div>In subduction zones, serpentinized oceanic mantle is expected to dehydrate above 600<!--> ^∘C due to antigorite breakdown (Atg-out reaction). Analysis of compilatory bulk composition of serpentinites shows that brucite (Brc) should also be an important hydrous component, capable of carrying water to depth. The Atg + Brc = Ol + H₂O reaction (R1) which occurs at lower temperature than Atg-out, is thus highly relevant for fluid release in subduction zones. Depending on the initial composition of the serpentinized mantle, R1 can produce more water than the Atg-out reaction. The consideration of most recent thermochemical data for brucite and serpentine solid-solutions shows that the R1 reaction proceeds in a narrow temperature range (&lt; 10<!--> ^∘C), implying relatively high dehydration rates. Thermochemical modeling also shows that the fluid released during R1 is highly magnesian ([Mg]/[Si] &gt; 100), i.e., likely to promote Mg metasomatism. In parallel, metamorphic olivine veins formed according to R1 in the Zermatt-Saas meta-ophiolite were examined. They are interpreted as magnesium-rich segregations resulting from the interaction between an Mg-rich fluid and the host serpentinite for around a hundred years. Furthermore, they are crosscut by brucite veinlets formed at R1 conditions or higher, which confirms, in agreement with thermodynamical modeling, that R1 is not a brucite-out reaction. Finally, P-T conditions of R1 were found to coincide with the location of Low Frequency Earthquakes recorded in the Mexican, Nankai and Cascadian subductions; this indirectly supports the role played by R1 as a significant source of fluid in subduction zones.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119602"},"PeriodicalIF":4.8,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145061238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Raman mapping reveals alpha radiation damage zonation and its annealing in Durango apatite","authors":"Xiaowei Zeng ,&nbsp;Guido Pastore ,&nbsp;Chuanbo Shen ,&nbsp;Alberto Resentini ,&nbsp;Hongyang Fu ,&nbsp;Chaoqun Yang ,&nbsp;Yannick Buret ,&nbsp;Pieter Vermeesch ,&nbsp;Marco G. Malusà","doi":"10.1016/j.epsl.2025.119636","DOIUrl":"10.1016/j.epsl.2025.119636","url":null,"abstract":"<div><div>The accumulation of alpha radiation damage and annealing mechanisms in apatite are crucial for thermochronological studies, yet they are challenging to explore. We conducted annealing experiments on four slices from one single Durango apatite crystal, utilizing Raman spectroscopy high-resolution mapping to investigate peak positions and full width at half maximum (FWHM) of the ν₁(PO₄) and ν₃(PO₄) bands. Additionally, LA-ICP-MS mapping was conducted on all samples to obtain their effective uranium content distribution. We assessed track density in various regions of the crystal, used a normalized track density reduction model to estimate original alpha radiation damage, and applied heavy ion irradiation to simulate the fission process and enhance the visibility of confined tracks. Our analysis shows that the FWHM of the ν₁(PO₄) band in Durango apatite is a reliable indicator of alpha radiation damage accumulation and does not correlate with fission track damage. We also found that the alpha radiation damage has negligible effect on fission-track annealing in young samples. While Raman peak position behaviour is still enigmatic, our results suggest that it may be influenced both by the chemical composition of apatite and by radiation damage accumulation. Our results underscore the potential of Raman spectroscopy as a powerful tool for assessing alpha radiation damage and annealing processes in apatite crystals.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119636"},"PeriodicalIF":4.8,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grain selection for representative detrital zircon age populations","authors":"Andreas Zametzer ,&nbsp;Maximilian Dröllner ,&nbsp;Milo Barham ,&nbsp;Christopher L. Kirkland ,&nbsp;C. Ashley Norris","doi":"10.1016/j.epsl.2025.119619","DOIUrl":"10.1016/j.epsl.2025.119619","url":null,"abstract":"<div><div>Detrital mineral analysis is deployed to address a diversity of Earth science questions, e.g., sediment provenance through zircon U–Pb age distributions. However, conventional approaches in sample preparation and grain selection involve inevitable sources of geological and laboratory bias that can distort the relative abundances of distinct age modes and thus skew geological interpretations. It has been established that detrital zircon grain shape reflects the combined result of conditions during primary formation and subsequent modification through Earth surface processes. Here, we explore if the population structure of 2D grain dimensions can be leveraged as a sub-sampling tool to produce more representative selections of analyses at lower sample numbers. We use two comparable detrital zircon populations with &gt; 1500 concordant zircon U–Pb analyses each from distinct depositional environments (fluvial vs. shoreline) with differing degrees of sorting and complexity in source contributions (as implied by U–Pb age structures). Our results demonstrate that selection of the largest – akin to human operator bias – or smallest zircon grains can result in statistically distinct populations until &gt; 1000 grains are chosen. Preserving a representative grain size distribution by sub-sampling to the grain shape population's mean value can circumvent this deleterious effect, irrespective of the degree of sorting. Results of ca. 600,000,000 model iterations imply that age population sampling variations fall within typical facies variability at a single stratigraphic level when analyzing ca. 240 grains and within the typical variability of geological formations when analyzing only ca. 70 grains using a representative selection strategy.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119619"},"PeriodicalIF":4.8,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Herschel impact basin probes the onset of a young ocean on mimas","authors":"C.A. Denton,&nbsp;A.R. Rhoden","doi":"10.1016/j.epsl.2025.119614","DOIUrl":"10.1016/j.epsl.2025.119614","url":null,"abstract":"<div><div>While observations of Mimas’ cratered surface suggest a largely inactive geologic history, measurements of its libration and pericenter precession indicate the presence of an ocean under an ice shell that is 20–30 km thick. Recent thermal-orbital models can reconcile the surface geology and interior constraints as long as Mimas’ ocean is young, most likely formed in response to a recent spike in eccentricity in the last ∼10 million years. We explore whether this timeline for ocean development is consistent with Mimas’ surface geology by revisiting the formation of its largest impact basin, Herschel, using iSALE-2D Our goal is to determine whether Herschel’s formation requires the presence of an ocean, as previous models suggest, or whether the impact instead occurred prior to melting of the ice shell, which could expand the time window for its formation. We find that Herschel’s morphology is consistent with a range of possible internal structures, including scenarios in which the ice shell is fully frozen, though in these cases the ice shell must be warm enough to be near its melting point. These formation conditions are consistent with inferences from crater age dating that Herschel is young, and thus, formed in close proximity to the geologically-recent growth of Mimas’ ocean.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119614"},"PeriodicalIF":4.8,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Timescales of magmatic-hydrothermal activity at the giant San Rafael tin deposit (Peru)","authors":"Sava Markovic ,&nbsp;Dawid Szymanowski ,&nbsp;Lorenzo Tavazzani ,&nbsp;Lisard Torró ,&nbsp;Kalin Kouzmanov ,&nbsp;Miroslav Kalinaj ,&nbsp;Cyril Chelle-Michou","doi":"10.1016/j.epsl.2025.119624","DOIUrl":"10.1016/j.epsl.2025.119624","url":null,"abstract":"<div><div>Recent research suggests that protracted magmatic activity may play a critical role in forming large metal endowments in magmatic-hydrothermal deposits. Here, we test whether this concept applies to tin systems associated with peraluminous (S-type) granites, focusing on the intrusive complex at San Rafael (Peru) that hosts the world’s largest and highest-grade primary Sn deposit (&gt;1.5 Mt of Sn at 3.7 %). We obtained a comprehensive (<em>n</em> = 187) set of high-precision U-Pb zircon dates from granites and mafic rocks that both pre- and post-date the cassiterite Sn ore according to crosscutting relationships. Individual granites exhibit large date dispersions (up to 1.7 Myr), which we evaluate in the context of magmatic and hydrothermal zircon origins, possibility of unmitigated Pb loss, and cryptic inclusion of older zircon cores. By integrating zircon compositions with field observations, we reconstruct 200–400 kyr of magmatic evolution in the crust – from 24.402 ± 0.019 Ma to final emplacement at shallow levels between 24.177 ± 0.004 Ma and 24.027 ± 0.028 Ma. Younger ages found in one sample of the ore-stage cassiterite (23.80 ± 0.25 Ma) and all samples of hydrothermal adularia (∼22.72–22.43 Ma) suggest that the mineralizing fluids were most likely not related to the cooling of the exposed intrusive complex, but instead to one or more younger magma pulses outgassing at depth. The duration of the magmatic build-up prior to Sn mineralization at San Rafael appears significantly shorter than in the largest porphyry copper systems, although we recognize that longer timescales may be resolvable in the unexposed portions of the system. Finally, we compared the metal tonnage and computed volumes of metal-sourcing melt at San Rafael (1.5 Mt of Sn and 77 km³ of melt) with the largest porphyry copper systems in magmatic arcs (112 Mt of Cu and &gt;1000 km³ of melt) to propose that more limited and episodic melt supply, alongside with restricted water availability in (post-)collisional S-type systems may limit the maximum endowments of Sn systems.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119624"},"PeriodicalIF":4.8,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Taken with a grain of salt: Resolving evaporite stratigraphy through accessory mineral geochronology","authors":"Jiankang Yi ,&nbsp;Christopher L. Kirkland ,&nbsp;Julien Bourdet ,&nbsp;Milo Barham ,&nbsp;Martin Danišík ,&nbsp;Andrew Feitz ,&nbsp;Peter W. Haines ,&nbsp;Brad McDonald ,&nbsp;Bruno V. Ribeiro ,&nbsp;Emanuelle Frery ,&nbsp;Claudio Delle Piane","doi":"10.1016/j.epsl.2025.119616","DOIUrl":"10.1016/j.epsl.2025.119616","url":null,"abstract":"<div><div>Rock salt caverns enable large-scale underground hydrogen storage, with potential significance for the green energy transition. However, in many salt-bearing basins, salt stratigraphy remains enigmatic due to inherent stratigraphic mobility and a lack of direct age constraints. Here, we present age and geochemistry of apatite and zircon grains from salt within the Canning Basin, Western Australia, which hosts Australia’s most extensive evaporite unit. The recovered apatite grains have shape, oxygen isotope, and geochemical affinity with magmatic volcanic crystals. The apatite grains yield a U–Pb age of 482 ± 13 Ma, coeval with volcanic ash beds elsewhere in the local stratigraphy. A syn-depositional interpretation of these apatite constrains the timing of salt deposition to ca. 482 Ma, ca. 40 Myr older than more well-constrained evaporites elsewhere in the Canning Basin, demonstrating multiple salt generations. This temporal constraint is supported by a maximum depositional age of 483 ± 12 Ma from detrital zircon grains. Previously unrecognised volcanic and clastic inputs of accessory minerals into salt provide a new means to constrain the stratigraphy and evolution of evaporitic basins, despite the mobility of salt. Such insights are critical for delineating the extent and geometry of salt bodies, whether bedded or diapiric, and thereby enhance site selection and risk assessment for hydrogen storage.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119616"},"PeriodicalIF":4.8,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Episodic copper mineralization in sedimentary basins: evidence from the Paradox Basin, USA","authors":"Eytan Bos Orent ,&nbsp;Mark D. Barton ,&nbsp;Jason D. Kirk","doi":"10.1016/j.epsl.2025.119620","DOIUrl":"10.1016/j.epsl.2025.119620","url":null,"abstract":"<div><div>Episodicity is common in mineral systems – it is responsible for mineral parageneses that form over timescales from 10 s of kyr to 10 s of Myr. New U-Pb dating of vein carbonate minerals reveals an unexpected epoch of fluid flow and sediment-hosted copper (Cu) mineralization between 18 and 3 Ma across large parts of the evaporite-dominated Paradox Basin. Sulfide-bearing carbonate veins from 9 locations with a mix of geologic settings and metal traps were analyzed by laser ablation inductively coupled mass spectrometry (LA-ICP-MS); of 37 samples examined, 13 from 9 mineral deposits had suitable U-Pb contents. Our results add to previously reported mid-Cretaceous to Oligocene ages for Cu mineralization in some of the same areas, highlighting the long-term and episodic nature of these systems. Cu mineralization requires appreciable fluid flux, yet the new ages mostly precede flow related to rapid exhumation (&lt;6 Ma) and post-date inferred flux maxima in the Mesozoic and early Cenozoic. Miocene flow of mineralizing fluids (oxidized brines) implies a change in hydrologic regime stimulated by some combination of partial removal of Paleogene and Late Cretaceous strata evidenced by new detrital zircon data, previously undocumented salt movement, and far-field influence by extension and magmatism beyond the Colorado Plateau. The new data imply a newly identified early stage of local exhumation, that in turn drove novel ore-forming hydrologic systems. These complexities illustrate the challenges in evaluating many sediment-hosted Cu deposits where hard-to-date mineralization can occur episodically from diagenesis to late-stage basin inversion, but usually happens over 10 s of Myr.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119620"},"PeriodicalIF":4.8,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Source fertility modulates crustal thickness variation along the Gakkel Ridge","authors":"Jianggu Lu ,&nbsp;Yejian Wang ,&nbsp;Tao Zhang ,&nbsp;William L. Griffin ,&nbsp;Weiwei Ding ,&nbsp;Yinxia Fang ,&nbsp;Yanhui Dong ,&nbsp;Weiqi Zhang ,&nbsp;Hanlin Wang ,&nbsp;Suzanne Y. O’Reilly ,&nbsp;Jiabiao Li","doi":"10.1016/j.epsl.2025.119617","DOIUrl":"10.1016/j.epsl.2025.119617","url":null,"abstract":"<div><div>The ultraslow-spreading Gakkel Ridge shows marked variation in crustal thickness at 31–100°E, decreasing from ∼7.5–8.9 km in the east to ∼2 km in the west, with peridotite exposures, but the causes of the crustal thickness variations remain unclear. This is explored using elemental and isotopic systematics of glasses and basalts from two segments at 85°E and 100°E (eastern Gakkel Ridge) combined with literature data from 31 to 85°E. Geochemical evidence suggests that the primary endmember composition of the samples had high Al₂O₃, N-MORB-like Sr-Nd-Hf-Pb isotopic systematics and slightly LREE-enriched patterns. The mantle source is probably an aluminum-rich fertile lherzolite related to deeper asthenospheric domains propagating south across the central Arctic at ∼150 km depth.</div><div>Thermodynamic modelling shows that the source potential temperatures and final depths of melting of the basalts at 31–100°E volcanic centres are all similar and thus cannot account for the variations in crustal thickness along the ridge. Integrating literature data that suggest the existence of prior refractory mantle residues along the Gakkel ridge, we propose that the sub-ridge uppermost mantle is a mixture of fertile and refractory mantle domains and the lateral variations in the proportion of fertile mantle domains modulate the change in crustal thickness along the axis.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"671 ","pages":"Article 119617"},"PeriodicalIF":4.8,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145011183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}