Earth and Planetary Science Letters最新文献

{"title":"Triple oxygen isotope signatures of cherts record pore-fluid composition and temperature across the opal-CT to quartz transition","authors":"Oskar Schramm ,&nbsp;Katharina Ebert ,&nbsp;Patrick J. Frings ,&nbsp;Andreas Pack ,&nbsp;Tommaso Di Rocco ,&nbsp;Volker Karius ,&nbsp;Nils Keno Lünsdorf ,&nbsp;Dieter Korn ,&nbsp;Daniel Herwartz ,&nbsp;Michael Tatzel","doi":"10.1016/j.epsl.2026.119889","DOIUrl":"10.1016/j.epsl.2026.119889","url":null,"abstract":"<div><div>Sedimentary chert is the diagenetic end-product of amorphous silica that first transforms to opal-cristobalite/tridymite (CT) and subsequently to microcrystalline quartz via dissolution and reprecipitation reactions. The ¹⁸O/¹⁶O and ¹⁷O/¹⁶O ratios (i.e. triple oxygen isotope composition, δ¹⁸O, Δ’¹⁷O) of cherts record equilibration with the pore fluids at the diagenetic temperatures prevalent during the opal-CT to quartz transition. Pore fluid oxygen isotope gradients emerge when secondary minerals, e.g. clay minerals form during burial. Here, we demonstrate that chert triple oxygen isotope compositions not in equilibrium with modern like seawater can be explained by changes in pore water δ¹⁸O and Δ’¹⁷O without invoking any alteration or different paleo-seawater. We demonstrate this using a suite of Carboniferous cherts that we collected from the same stratigraphic level at five locations in the Rhenish Massif, Germany, spanning a range of inferred burial rates. The precursor sediments were deposited in the marine Rhenohercynian Basin and were subject to peak diagenetic temperatures of up to 279 ± 37 °C upon folding and thrusting. Their triple oxygen trajectory cannot be explained by any realistic paleo-seawater composition. Using our numerical silica diagenesis model, we find that the chert isotope signatures are explained by a formation temperature between 20–35 °C and a pore fluid composition of -7 to -14‰ δ¹⁸O consistent with a pore fluid gradient of -13.5 ‰ km^-1 across the Rhenohercynian Basin. This suggests that triple oxygen isotope compositions of chert systematically record near-surface conditions and therefore represent a valuable resource for paleoenvironmental research.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119889"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185575","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":"Multi-pulse and crystal-laden emplacement of the Tunnel Dike: implications for flood basalt volcanism","authors":"Ryan M. Currier ,&nbsp;Paulo J. Hidalgo ,&nbsp;Tushar Mittal ,&nbsp;Jada Nimblett ,&nbsp;Lucian Bitner ,&nbsp;Taiylor Williams ,&nbsp;Bil Schneider","doi":"10.1016/j.epsl.2026.119895","DOIUrl":"10.1016/j.epsl.2026.119895","url":null,"abstract":"<div><div>Flood basalt provinces, like the Columbia River Basalts (CRB), signify vast volcanic activity capable of inducing paleoclimatic shifts and extinction events via extensive volatile emissions. Two competing models exist for their rates of emplacement: one argues for slow, prolonged eruption based on lava flow morphology, while the other argues for rapid emplacement based on thermally constrained modeling of dikes, assuming crystal-poor, low-viscosity magmas fed through wide conduits. We test these assumptions by investigating the Tunnel Dike, a Chief Joseph Dike Swarm dike thought to be the feeder for several significant CRB flows. Thermal modeling indicates the dike was emplaced as relatively cool, crystal-laden magma, assembling incrementally to its final thickness. Crystal size distributions across the dike exhibit aphanitic margins which transition sharply into a porphyritic interior, where plagioclase commonly displays high-temperature deformation, with spatial distributions suggesting granular flow. These lines of evidence point to a multi-pulse, crystal-rich mush emplacement of the Tunnel Dike. Under these conditions, magmatic flux would have been orders of magnitude slower than previous estimates, aligning with flux rates based upon lava flow morphology of flood basalts and with peak effusion rates of the 1783 Laki fissure eruption. Although based on a single dike, the textures observed in the Tunnel Dike appear to be widespread across the CJDS, suggesting that crystal-rich, incremental dike emplacement may be more broadly characteristic of Columbia River Basalt magmatism. These findings carry implications for estimates of volatile emissions, and, consequently, paleoclimate modeling.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119895"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185574","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":"Spatial variability and mechanics in aeolian ripples: A case study in Chilean Patagonia","authors":"Tyler R. Gough ,&nbsp;Chris H. Hugenholtz ,&nbsp;Paul R. Nesbit ,&nbsp;Thomas E. Barchyn","doi":"10.1016/j.epsl.2026.119892","DOIUrl":"10.1016/j.epsl.2026.119892","url":null,"abstract":"<div><div>The transport capacity, sediment supply, and sediment availability in an aeolian landscape exert control on its bedforms. In this work, we use a 200 m long megaripple field forming on the 400 m high El Chingue escarpment in Chilean Patagonia as a case study in evaluating how spatial differences in these factors affect bedforms. Strong westerly winds encounter the steep escarpment of El Chingue, which creates a speed-up effect and increased transport capacity at the ridgeline followed by a trend of decreasing wind speed and transport capacity across the megaripple field. We describe and analyze the morphological, granulometric, and structural responses of the megaripples to this spatial trend. Results indicate that upwind megaripples are smaller, have poor sorting, thin armor layers, and no cross-bedding. In the middle of the field, the megaripples are larger, have thicker armor layers, a distinct bimodal distribution, and well-developed cross-bedding. At the downwind margin, megaripples are increasingly vegetated, generally flatter, and lose the distinct cross-bedding and bimodality. This transition of morphology, granulometry, and structure through the megaripple field reflects the spatial trend in transport capacity and aligns with current understanding of megaripple morphodynamic regimes. However, it highlights that different regimes may occur simultaneously within the same field. Broadly, these results emphasize the dynamic nature of megaripples and encourages the further application of a spatial analysis and sediment state understanding for ripple-scale bedforms to improve understanding of similar features across environments.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119892"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185586","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":"Why the end-Guadalupian biotic crisis differs from mass extinctions: Insights from high-precision geochronology and carbon cycle modeling","authors":"Qiong Wu ,&nbsp;Zhang-shuai Hou ,&nbsp;Jahandar Ramezani ,&nbsp;Dong-xun Yuan ,&nbsp;Hua Zhang ,&nbsp;Wen-qian Wang ,&nbsp;Quan-feng Zheng ,&nbsp;Yi-chun Zhang ,&nbsp;Fei-fei Zhang ,&nbsp;Guang-yi Wei ,&nbsp;Shu-han Zhang ,&nbsp;Yue Wang ,&nbsp;Douglas H. Erwin ,&nbsp;Yi-gang Xu ,&nbsp;Shu-zhong Shen","doi":"10.1016/j.epsl.2026.119898","DOIUrl":"10.1016/j.epsl.2026.119898","url":null,"abstract":"<div><div>Despite extensive release of carbon from eruptive pulses of Emeishan Large Igneous Province (ELIP) volcanism and increased temperatures, associated biotic crisis across the Guadalupian–Lopingian boundary (middle Permian) did not rise to the level of a mass extinction. Here we integrate new high-precision CA-ID-TIMS U-Pb zircon ages from South China, refining the Guadalupian–Lopingian boundary age to 259.857 ± 0.084 Ma (95 % C.I.) with carbon isotope and temperature records as the framework for carbon cycle modeling. We show that the magnitude and rate of carbon release during two warming phases associated with the ELIP eruptive pulses were substantially lower than those that drove Phanerozoic mass extinctions. Our findings provide a new explanation for why the end-Guadalupian biotic crisis did not escalate into a rapid mass extinction. This work suggests a threshold for the carbon injection rates required to generate climatic perturbations of sufficient magnitude and pace to trigger severe environmental stress and advances our understanding of the links between large igneous province volcanism, climate perturbations, and biotic resilience in Earth’s past.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119898"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185656","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":"Reply to the comment of Rasmussen et al., on: Evolution of iron formation to ore during Ediacaran to early Paleozoic tectonic stability","authors":"Anthony J. Fuentes ,&nbsp;Liam Courtney-Davies ,&nbsp;Rebecca Flowers ,&nbsp;Yiming Zhang ,&nbsp;Nicholas Swanson-Hysell","doi":"10.1016/j.epsl.2026.119865","DOIUrl":"10.1016/j.epsl.2026.119865","url":null,"abstract":"","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119865"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090146","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":"Accumulation of remineralised carbon and nutrients in the mid-depth Atlantic during Heinrich Stadial 1 and the Younger Dryas","authors":"Joseph A. Stewart ,&nbsp;Laura F. Robinson ,&nbsp;James W.B. Rae ,&nbsp;Naomi Pratt ,&nbsp;Tianyu Chen ,&nbsp;Maria Luiza de Carvalho Ferreira ,&nbsp;Andrea Burke ,&nbsp;Tao Li ,&nbsp;Tina van de Flierdt","doi":"10.1016/j.epsl.2026.119866","DOIUrl":"10.1016/j.epsl.2026.119866","url":null,"abstract":"<div><div>Atmospheric CO₂ and the temperature of the interior Atlantic Ocean both increased in 2-steps during the last deglaciation, particularly during Heinrich Stadial 1 (HS1; ∼16 ka) and the Younger Dryas (YD; ∼12 ka). However, what drove these punctuated rises remains a long-standing question. The role of deep-ocean carbon storage, release, and redistribution continues to be debated. To establish the role of ocean circulation in deglacial carbon and nutrient cycling, we present new multi-proxy data in sub-fossil corals from mid-depths in the Equatorial Atlantic, including boron isotopes (δ¹¹B; seawater pH), Ba/Ca (seawater [Ba] and refractory nutrients), and neodymium isotopes (ε_Nd; provenance of seawater signal). Corals are dated to a precise radiometric age scale and combined with previously published radiocarbon and temperature proxy measurements on the same samples. Our data reveal abrupt intervals (∼500 years) of notably low pH, Ba-rich, and radiocarbon-depleted (old) waters at 15.4 and 12.0 ka during HS1 and the YD at depths of ∼1700 m. However, very low ε_Nd (unradiogenic) values suggest that these corals were bathed in northern-sourced Atlantic waters throughout the deglaciation. These results imply that these (old) carbon- and nutrient-rich intermediate waters were not sourced from the carbon- and nutrient-rich Southern Ocean via Antarctic Intermediate Water (AAIW). Instead, carbon and nutrient accumulation at mid-depths in the tropical Atlantic was likely the result of remineralisation of organic matter at times of Atlantic Meridional Overturning Circulation (AMOC) slowdown. The Atlantic Ocean interior was therefore accumulating heat and carbon during these times when deepwater flushing was minimal, thus acting to partially dampen atmospheric CO₂ rise and warming caused by ventilation of the Southern and Pacific Oceans.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119866"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090729","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":"Large-scale slab dynamics as drivers of seismicity: Modeling earthquakes in the izu-bonin-mariana subduction zones","authors":"Yida Li ,&nbsp;Neil M. Ribe ,&nbsp;Zhe Jia","doi":"10.1016/j.epsl.2026.119878","DOIUrl":"10.1016/j.epsl.2026.119878","url":null,"abstract":"<div><div>Subduction zones host the majority of global earthquakes, ranging from shallow megathrust and outer-rise earthquakes to deep intraplate seismicity. Although it is well-established that subducting slabs supply the primary energy driving most earthquakes, the quantitative relationship between slab dynamics and seismic events remains poorly understood. Here we develop a comprehensive 3D geodynamic model of the Izu-Bonin-Mariana subduction system to quantitatively connect long-term slab dynamics with earthquake activity. Based on an analytical thermal model combined with slab geometry, we find that earthquakes predominantly occur under conditions cooler than  ∼ 900^∘C, defining a thermal boundary for the seismogenic zone. Within this zone, we identify a notable spatial correlation between the modeled energy dissipation rate and the observed distribution of seismicity, indicating that seismicity is intrinsically driven by long-term tectonic deformation. Furthermore, our comparison of the modeled stress state predictions with observed earthquake focal mechanisms reveals that both shallow megathrust and outer-rise earthquakes, as well as deep earthquakes associated with plate bending at the mantle transition zone, can be explained by slab dynamics. By analyzing the misfit between modeled and observed focal mechanisms, we further constrain slab rheology, finding that shallow earthquakes favor a relatively weak slab (yield stress of 100 – 150MPa), while deep earthquakes prefer a stronger slab (300 - 500MPa) accompanied by a 10 – 100–fold viscosity increase at the 660 km phase transition. Taken together, our results underscore the profound link between earthquake occurrence and the large-scale, long-term dynamics of mantle flow and subduction.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119878"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090734","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":"Reply to the comment on “The influence of cementation on fault stability”","authors":"G. Volpe ,&nbsp;R. Affinito ,&nbsp;L. Calzolari ,&nbsp;G. Pozzi ,&nbsp;C. Marone ,&nbsp;C. Collettini","doi":"10.1016/j.epsl.2026.119867","DOIUrl":"10.1016/j.epsl.2026.119867","url":null,"abstract":"","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119867"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001678","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":"Zircon deformation features reveal sequence of transient high stress, tension and shearing during seismic faulting: A case study from the Ivrea-Verbano Zone, Italy","authors":"Sandra Piazolo ,&nbsp;Antonio Langone","doi":"10.1016/j.epsl.2026.119858","DOIUrl":"10.1016/j.epsl.2026.119858","url":null,"abstract":"<div><div>The mechanisms associated with the propagation of fault ruptures remain debated in terms of sequence of events, processes and magnitude of stresses involved. Microstructures of zircon grains located within and in the immediate vicinity of pseudotachylyte veins reveal a sequence of events transient in time and space and allow recognition of different processes during rupture. The dynamic rupture causes, at its propagating tip, a damage zone of several centimetres thickness. In this damage zone, zircon grains exhibit crystal-plastic deformation signatures ranging from crystal lattice bending continuous throughout whole grains, to distinct planar deformation bands and {112} twin lamellae. Presence of planar deformation bands and {112} twin lamellae suggest locally high stresses, based on similar features reported from meteorite impacts. Absence of well-developed subgrains indicate dominance of low temperature plasticity at the rupture tip. Subsequently, those grains with highest dislocation densities undergo in-situ grain fragmentation. The observed correlation of grains with very high dislocation densities and in-situ grain fragmentation suggests that the effective tensile strength of these grains is sufficiently decreased by the high stored elastic energy to cause their fragmentation when subject to tensile stresses in the wake of the propagating rupture tip. Subsequent displacement along connected damage zone fracture surfaces results in pseudotachylytes formation.</div><div>Our data shows that dynamic rupture initiation and propagation results in stresses heterogeneously distributed in space, magnitude and sign causing both ductile and brittle deformation. Our study highlights the value of the accessory mineral zircon in deciphering the nature of rupture zone dynamics.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119858"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036666","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":"Induced seismicity in the southern Sichuan basin regulated by heterogeneous folding","authors":"Bingfeng Zhang ,&nbsp;Xuewei Bao ,&nbsp;Mengfan Jiang ,&nbsp;Kecheng Zhou","doi":"10.1016/j.epsl.2026.119860","DOIUrl":"10.1016/j.epsl.2026.119860","url":null,"abstract":"<div><div>The potential for strong induced earthquakes in industrial production fields is largely controlled by the spatial arrangement of pre-existing faults shaped by regional tectonics. The 2021 Ms 6.0 Luxian earthquake in the southern Sichuan basin is an unusual case in which the seismogenic fault geometry deviates from the prevailing regional stress field and geological framework. To date, the seismogenic environment and the tectonic processes responsible for this destructive event remain poorly understood. In this study, we present a sedimentary shear-wave velocity model and eleven moment tensor solutions across the Luxian shale gas field, derived using data collected by our newly deployed seismic network. Our results reveal previously unrecognized, nearly reversed lateral variations in the amplitudes of synclinal low-velocity anomalies between terrestrial and marine strata, in addition to a first-order velocity contrast that correlates with the regional anticline–syncline architecture. The central Yujiasi syncline exhibits weaker low-velocity anomalies in the shallow terrestrial strata than areas to the north and south, reflecting lower strain intensity likely influenced by shallower décollement layers. Detected seismicity and anomalous reverse-faulting events with fold-parallel P-axes (including the Ms 6.0 earthquake) cluster mainly within two strain transition zones of the Yujiasi syncline, where stress is expected to concentrate and form fold-normal fault planes. These observations provide direct evidence that heterogeneous folding regulates the spatial distribution of induced seismicity in the southern Sichuan basin. They also help identify areas susceptible to induced seismic hazards and provide guidance for planning hydraulic fracturing operations in the region.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"679 ","pages":"Article 119860"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036670","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}