Earth and Planetary Science Letters最新文献

{"title":"Changing volatile emissions and sources along the Ethiopian Rift","authors":"Abate A. Melaku ,&nbsp;Gemechu B. Teferi ,&nbsp;Takele Mihretie ,&nbsp;Snorri Gudbrandsson ,&nbsp;Yared Sinetebeb ,&nbsp;Peter H. Barry ,&nbsp;Tobias P. Fischer ,&nbsp;Finlay M. Stuart ,&nbsp;Ugur Balci ,&nbsp;Sæmundur A. Halldórsson ,&nbsp;Chris J. Ballentine ,&nbsp;Darren J. Hillegonds ,&nbsp;Emma L. Chambers ,&nbsp;Derek Keir ,&nbsp;Richard Bates ,&nbsp;William Hutchison","doi":"10.1016/j.epsl.2025.119782","DOIUrl":"10.1016/j.epsl.2025.119782","url":null,"abstract":"<div><div>Rift volcanoes are sites of intense volatile emissions. However, major uncertainties remain about the magnitude of rift volatile fluxes, particularly for greenhouse gases (e.g. CO₂) and whether along-rift variations in degassing relate to changing mantle sources and/or rifting processes (i.e. melt production and lithospheric thinning). Here, we investigate CO₂ flux and gas isotopes in Ethiopia; a mature, plume-influenced continental rift. We focus on one of the largest caldera volcanoes, Bora-Baricha-Tulu Moye (BBTM), which is situated in a region of high mantle melt production in the Central Main Ethiopian rift (∼500 km south-west the putative plume head). BBTM gases are characterized by plume-like ³He/⁴He values up to 17 R_a (the highest ever observed in Ethiopian Rift fumaroles) and we calculate total magmatic CO₂ flux of 757–901 t d^-1 (making BBTM the largest volcanic CO₂ emitter in the Ethiopian Rift). Using our CO₂ flux measurements, we estimate total CO₂ emissions from Ethiopia’s volcanic systems to be 2500–9200 kt yr^-1 and reveal important along-rift variation in CO₂ flux. High CO₂ flux sectors are found in Central Afar, as well as the Northern and Central Main Ethiopian Rift. These sectors are all regions of high partial melt content (evidenced by low seismic velocity in the underlying mantle) and also show the greatest ³He/⁴He values (&gt;14 R_a). Cooccurrence of high mantle melt production, elevated CO₂ emissions and high ³He/⁴He demonstrates that in mature continental rifts carbon emissions and plume volatile contributions are particularly elevated in regions of greatest lithospheric thinning and mantle melting.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"676 ","pages":"Article 119782"},"PeriodicalIF":4.8,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145789867","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":"Isotopic constraints on the Barium subduction cycle","authors":"Qasid Ahmad ,&nbsp;Martin Wille ,&nbsp;Carolina Rosca ,&nbsp;Thomas Pettke ,&nbsp;Jörg Hermann ,&nbsp;Stephan König","doi":"10.1016/j.epsl.2025.119789","DOIUrl":"10.1016/j.epsl.2025.119789","url":null,"abstract":"<div><div>Subduction processes regulate elemental cycling and consequently the composition of Earth’s geochemical reservoirs - mantle, crust, atmosphere, and hydrosphere, exerting far-reaching effects for the evolution of life. Barium (Ba) is essential for understanding crust-mantle recycling, especially since over 90 % of Ba in arc lavas originates from subducted materials. While Ba enrichments in arc lavas have long been attributed to contributions from oceanic crust derived aqueous fluids, recent studies highlight hydrous sediment melts as a key carrier. Here, we present high-precision Ba isotope data (δ^138/134Ba) of input and output from the Tongan subduction zone. The results show that Ba is not predominantly supplied by the subducting oceanic crust. Instead, most Ba can be traced back to subducting sediments from which it is released in two stages. During early subduction, sedimentary barite dissolves and releases isotopically heavy Ba via aqueous fluids into the serpentinized mantle wedge, where this Ba is later remobilized during subsequent breakdown. With continued slab descent, remaining lithogenic phengite releases isotopically lighter Ba, which is recycled at subarc depths by hydrous melting. Both mechanisms can explain the entire range of Ba/Th and δ^138/134Ba in Tongan arc lavas without requiring Ba isotope fractionation between fluids and solids. These results from the endmember setting of Tonga, with minimal subducting sediments, imply higher proportion of sediment-derived Ba in other arcs worldwide. The Forearc Serpentinite Signature (FSS), which is created by the interaction of the mantle wedge with sediment-derived fluids at low temperatures (&lt;600 °C), represents an additional fluid endmember that must be considered in the genesis of arc lavas. Lithogenic Ba that is not completely released at subarc depths can be further subducted into the deeper mantle, where it may later enrich mantle domains that source mid-ocean ridge and hotspot lavas. The relative proportions of sedimentary components in subducted slabs have changed over Earth’s history, highlighting the link between arc magma and mantle compositions and long-term shifts in Earth’s surface (bio)geochemical cycles.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119789"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797773","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":"Ultramafic float rocks at Jezero crater (Mars): excavation of lower crustal rocks or mantle peridotites by impact cratering?","authors":"O. Beyssac ,&nbsp;E. Clavé ,&nbsp;O. Forni ,&nbsp;A. Udry ,&nbsp;A.C. Pascuzzo ,&nbsp;E. Dehouck ,&nbsp;P. Beck ,&nbsp;L. Mandon ,&nbsp;C. Quantin-Nataf ,&nbsp;N. Mangold ,&nbsp;G. Lopez-Reyes ,&nbsp;C. Royer ,&nbsp;O. Gasnault ,&nbsp;T.S.J. Gabriel ,&nbsp;L. Kah ,&nbsp;S. Schröder ,&nbsp;J.R. Johnson ,&nbsp;T. Bertrand ,&nbsp;B. Chide ,&nbsp;T. Fouchet ,&nbsp;A. Cousin","doi":"10.1016/j.epsl.2025.119746","DOIUrl":"10.1016/j.epsl.2025.119746","url":null,"abstract":"<div><div>Based on observation and data from meteorites and in situ scientific missions, experiments as well as models, the Martian mantle is assumed to share some compositional and mineralogical affinity with the terrestrial mantle. However, there might be subtle differences like the Martian mantle being more ferroan. Yet, we do not have any direct analysis of a Martian mantle rock to confirm this assumption. NASA’s <em>Perseverance</em> rover found olivine-rich boulder-sized float rocks on the upper Jezero fan (Mars). These boulders have an ultramafic composition and their mineralogy is dominantly composed of Fo_73±3 olivine with high-Mg orthopyroxene, Cr-rich Ti-Fe oxides and minor plagioclase and high-Ca pyroxene. Microtextural and petrological analysis reveals that these minerals crystallized at equilibrium. In addition, these boulders are different from all the bedrocks analyzed by <em>Perseverance</em> along its traverse which are crustal igneous rocks and sediments. Comparing our data to Martian meteorites and available Mars bulk silicate models (BSM), we discuss that these boulders could represent primitive melts and/or lower crustal material, and we specifically hypothesize that they could be mantle peridotites. We propose that these putative mantle rocks could have been excavated by the succession of impacts from the shallow mantle or lower crust in the Isidis region where Jezero crater is located. These olivine-rich boulders could thereby constitute the first direct analysis of a Martian mantle rock.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119746"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145693279","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":"Three-dimensional density structure underneath the Marius Hills volcanic complex on the Moon","authors":"Shiyu Zhang ,&nbsp;Bo Chen ,&nbsp;Qian Huang ,&nbsp;Changyi Xu ,&nbsp;Xiaolong Wei","doi":"10.1016/j.epsl.2025.119770","DOIUrl":"10.1016/j.epsl.2025.119770","url":null,"abstract":"<div><div>Marius Hills, located in the central Oceanus Procellarum on the nearside of the Moon, is a significant volcanic complex, characterized by hundreds of domes and cones. Understanding its subsurface density structure is essential for enhancing our knowledge of lunar volcanic activity and its evolutionary history, yet it remains controversial. To investigate the density structure underneath Marius Hills, we developed a gravity inversion method based on the L1 norm and total variation regularization in spherical coordinates. We validated the method through a synthetic model test. We then applied it to the inversion of gravity data derived from the GRAIL mission in Marius Hills. Our results reveal two distinct high-density anomalies in the northern and southern segments of Marius Hills. The northern anomaly is located at 14–29 km depth directly beneath the shield volcano of Marius Hills, with a density contrast of ∼620 kg/m³ and a volume of about 60 × 60 × 15 km³. The southern anomaly exhibits a density contrast of ∼440 kg/m³ and a size of 75 × 75 × 15 km³ at depths of 18–33 km. These two dense anomalies are likely solidified basaltic magma chambers situated near the crust-mantle boundary, that served as magma sources for the volcanic activities in Marius Hills.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119770"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145734592","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":"Melting phase relations in Fe-FeS under Martian core pressures: Crystallization of Fe12S7 at the inner core?","authors":"Fumiya Sakai ,&nbsp;Kei Hirose","doi":"10.1016/j.epsl.2025.119785","DOIUrl":"10.1016/j.epsl.2025.119785","url":null,"abstract":"<div><div>Sulphur is believed to be a major light element in the Martian core, and if it is the single light element, 15 wt% to 34 wt% S is required to explain the mean core density deduced from the recent InSight observations. The existing Fe-FeS phase diagram at 21 GPa suggests the crystallization of Fe₃₊<em>_x</em>S₂ from such sulphur-rich core liquids, but melting phase relations at ∼40 GPa corresponding to Mars’ centre pressure are not known yet. Here we performed both subsolidus and melting experiments on Fe + 22.3–27.5 wt% S samples between 26 and 175 GPa to constrain the S-rich portion of the Fe-FeS phase diagram. Present experiments were conducted up to a pressure range much higher than that for the Mars’ core in order to constrain the melting curve and compression behaviour of Fe₁₂S₇. Synchrotron X-ray diffraction measurements demonstrated that Fe₁₂S₇ is formed above 27 GPa and Fe_3.2S₂ decomposes into Fe₁₂S₇ + FeS at least above 29 GPa. We also found that Fe₂S incongruently melts to liquid + Fe₁₂S₇, showing that Fe₁₂S₇ crystallizes from liquid Fe containing 20 to 25 wt% S under the proposed pressure and temperature at the Mars’ centre. Fe₁₂S₇ forms also from S-rich Fe-S-C/Fe-S-O core liquids following the crystallization of Fe₃C/FeO. Furthermore, the equation of state of Fe₁₂S₇ indicates its density is higher than the range of observed Martian mean core density. These suggest that the Martian inner core, if it exists, likely includes Fe₁₂S₇, even when considering the presence of other light elements.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119785"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797774","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":"Long-term faulting history of the Central Taurides based on U-Pb dating of syn-tectonic calcites","authors":"Tunahan Aykut ,&nbsp;I. Tonguç Uysal ,&nbsp;Cengiz Yıldırım ,&nbsp;Timur Ustaömer ,&nbsp;Nicole Leonard","doi":"10.1016/j.epsl.2025.119763","DOIUrl":"10.1016/j.epsl.2025.119763","url":null,"abstract":"<div><div>The Central Taurides, located along the southern margin of the Central Anatolian Plateau (CAP), form a distinctive physiographic unit characterized by a steep mountain belt, high fault density, and diverse kinematic structures. It represents a key geological archive of subduction and the initial stages of collision in the Eastern Mediterranean. Although the geological evolution and origin of high-relief mountain development in this area remain extensively debated, the faulting history is poorly constrained due to a lack of direct isotopic age data. To comprehend the link between brittle deformation, uplift and plateau margin development, we investigate faulting history using kinematic and microstructural analyses combined with U-Pb dating of syn-tectonic calcites. U-Pb dating of forty-one syn-tectonic calcites indicate three faulting phases from the Late Cretaceous to the Quaternary. Thrust/reverse faulting occurred in the Late Cretaceous, followed by strike-slip faulting from the Early Eocene to the Early Miocene. Normal faulting became prevalent from the Early Miocene to the Quaternary. This study confirms compressional control on faulting during the Late Cretaceous in southern Türkiye. We also identify a previously unrecognized strike-slip faulting phase between the Early Eocene and the Early Miocene and demonstrate that extensional deformation in the Central Taurides began in the Early Miocene, rather than in the Middle/Late Miocene as suggested by earlier studies. Our results suggest that post-Oligocene structural patterns have been shaped by extensional processes. This study provides new constraints on multiple tectonic phases along the southern CAP margin, offering key insights into the geodynamic evolution of the Eastern Mediterranean.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119763"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659049","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":"The role of crystal-bubble interactions, outgassing and magma composition in the ascent dynamics of alkaline magmas: Implications for eruptions at Vesuvius","authors":"Fabio Arzilli ,&nbsp;Giuseppe La Spina ,&nbsp;Emily C. Bamber ,&nbsp;Daniele Morgavi ,&nbsp;Lorenzo Fedele ,&nbsp;Lucia Mancini ,&nbsp;Marko Prašek ,&nbsp;Ileana Santangelo ,&nbsp;Giulia Chiominto ,&nbsp;Annamaria Perrotta ,&nbsp;Thomas Lemaire ,&nbsp;Hélène Balcone-Boissard ,&nbsp;Daniele Giordano ,&nbsp;Claudio Scarpati","doi":"10.1016/j.epsl.2025.119771","DOIUrl":"10.1016/j.epsl.2025.119771","url":null,"abstract":"<div><div>Intermediate to evolved alkaline magmas (phono-tephritic, tephri-phonolitic and phonolitic) exhibit a wide range in eruptive style and have produced some of the most catastrophic eruptions in human history, such as the 79 AD Plinian eruption of Vesuvius (Italy). However, eruptive dynamics are driven by complex, non-linear conduit processes during magma ascent, requiring a holistic approach to investigate their influence on explosivity. This study integrates synchrotron radiation X-ray computed microtomography (SRµCT) with a 1D steady-state conduit model, to investigate how crystal-bubble interactions, pre-eruptive conditions, outgassing, and magma composition affect eruptive style at alkaline volcanic systems, using Vesuvius as a case study.</div><div>We analyse pyroclasts from the 79 AD Plinian and 1944 lava-fountaining eruptions using SRμCT. Our SRµCT results reveal that heterogeneous bubble nucleation can be promoted further by leucite crystals, contributing to the high bubble number densities (&gt;10⁴ mm⁻³) observed in Plinian products. Despite high bubble connectivity, low throat-pore size ratios (the ratio between the radii of the throat and connected vesicles) and elevated tortuosity restrict gas–melt separation during fast magma ascent, promoting fragmentation. Numerical simulations reveal tephri-phonolitic and phonolitic magmas are prone to fragmentation across diverse conditions, producing highly explosive eruptions. Only relatively high temperatures (&gt;1050 °C) and low bubble number densities (10² to 10³ mm^-3) can promote lava flow and fountaining activity. Instead, phono-tephritic magmas exhibit highly explosive eruptions at considerably lower temperatures (&lt;950 °C). Temperature controls magma viscosity, influencing the ascent rate and the outgassing efficiency, which, in turn, affects conduit dynamics and the eruptive behaviour.</div><div>Our findings highlight that for alkaline systems, the parameter space which is conducive to highly explosive eruptions expands as the magma composition evolves and its viscosity increases. These insights enhance our understanding of eruption mechanisms, providing critical insights for assessing volcanic hazard and emergency planning at alkaline volcanic systems.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119771"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145734589","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":"Tectonic structures and stress state associated with seamount subduction in accretionary prism. Implications for slip behavior","authors":"Alexis Gauthier ,&nbsp;Nadaya Cubas ,&nbsp;Laetitia Le Pourhiet","doi":"10.1016/j.epsl.2025.119767","DOIUrl":"10.1016/j.epsl.2025.119767","url":null,"abstract":"<div><div>Seamounts on oceanic plates are thought to affect the dynamics of accretionary prism at subduction zones, particularly the slip behavior. Geophysical studies show that pore fluid overpressure is associated with the nucleation of shallow slow slip events (SSEs). We use numerical simulations in which the subducting plate bends in response to tectonic, gravitational collapse and surface processes to capture structural complexities arising from the subduction of buried seamounts and compute the resulting stress state. We show that tectonic slices of undeformed sediments develop on both sides of the seamount and that a basin forms atop the seaward slice. These structures, recognizable in seismic data, represent the long-term tectonic signature of seamount subduction.</div><div>Gravitational collapse only occurs when a critical lengthscale, we quantified, of perturbed accretionary prism is reached. Seamounts that are small enough, instead get decapitated and do not perturb the prism over a sufficient lengthscale to trigger gravitational collapse.</div><div>Stress analysis reveals that the seaward side of the seamount is under an extensional regime, whereas its landward side is in a compressive state. We thus propose that sustained pore fluid overpressure can only develop on the landward side. This mechanism supports observations along Hikurangi, where a highly reflective zone, interpreted as a zone of pore fluid overpressure, has been imaged downdip of the Papaku seamount. Since this zone coincides with the largest slip magnitudes of shallow SSEs, we propose that the landward slice of undeformed sediments presents favorable conditions for SSEs nucleation.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119767"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145734591","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":"Friction heterogeneity constrains rupture dynamics across a narrow seismogenic zone: The 2021 Mw 7.4 Maduo Earthquake (Eastern Tibet)","authors":"Kuilin Xiao ,&nbsp;Qiang Qiu","doi":"10.1016/j.epsl.2025.119769","DOIUrl":"10.1016/j.epsl.2025.119769","url":null,"abstract":"<div><div>Slip magnitude and rupture extent are crucial for understanding fault mechanics and seismic hazard but remain poorly resolved at depth. Here, we integrate GNSS and remote sensing observations with a resolution-optimized slip inversion technique to determine the coseismic slip distribution due to the 2021 Mw 7.4 Maduo earthquake (Tibet). Our high-resolution model reveals three key aspects unresolved in prior studies: a larger maximum slip of ∼9 m on the eastern fault, a moderate shallow slip deficit (SSD) of ∼40% above ∼2 km depth, and a narrower seismogenic layer confined to depths of 2–8 km. Further, we conduct physics-based 2D earthquake-cycle models, constrained by InSAR data and geological information, which reconcile these observations and indicate a transition from rate-weakening (seismogenic depths) to rate-strengthening (shallow depths), explaining both the SSD and along-strike variations in seismogenic zone width. Coulomb stress transfer calculation from our model successfully forecasts aftershocks over days to years, providing a benchmark for future seismic hazard assessment. These findings imply heightened seismic risk in the eastern Bayan Har Block, necessitating focused monitoring.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119769"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797727","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":"Variable roles of oceanic transform faults in plume dispersion along segmented mid-ocean ridges","authors":"Fan Zhang ,&nbsp;Sibiao Liu ,&nbsp;Lars H. Rüpke ,&nbsp;Yiming Luo ,&nbsp;Ming Chen ,&nbsp;Xubo Zhang ,&nbsp;Lei Zhao ,&nbsp;Yinuo Zhang ,&nbsp;Zhanying Chen ,&nbsp;Jian Lin","doi":"10.1016/j.epsl.2025.119766","DOIUrl":"10.1016/j.epsl.2025.119766","url":null,"abstract":"<div><div>Transform faults are integral to the mid-ocean ridge system, yet their role in modulating mantle plume dispersion along segmented ridges remains poorly understood. By compiling and analyzing the tectonic characteristics of 24 global plume–ridge–transform systems, we categorize them into three types: on-ridge, off-ridge, and on-transform–fracture zone interactions. Using 3D geodynamic models, we evaluate how transform fault length, plume–transform distance, plume–ridge distance, and spreading rate influence plume behavior. Our results reveal that transform faults can play three distinct roles in plume dispersion, depending on plume positioning relative to the ridge–transform system. Barrier-like behavior occurs when transform offset increases the separation between the plume and two ridge segments and plume material needs to cross the lithospheric discontinuity boundary along the transform fault to spread, thus strongly reducing along-ridge plume dispersion (e.g., on-ridge plumes and most off-ridge plumes beneath the outside corner of a ridge segment). Bridge-like behavior arises when plumes beneath fracture zones or near ridge–transform intersections bypass these discontinuities, enabling dispersion to both ridge segments with little reduction. Booster-like behavior emerges under certain geometries, such as inside-corner plumes or plumes beneath transform centers. In these scenarios, dispersion is enhanced by shorter plume–ridge distance, avoidance of lithospheric discontinuities, and localized strengthening of along-ridge mantle flow near the transform fault induced by strike-slip motion. These findings highlight the geometric controls on plume–ridge–transform interactions and underscore the complexity of transform fault influence in plume dynamics.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"675 ","pages":"Article 119766"},"PeriodicalIF":4.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659054","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}