Earth and Planetary Science Letters最新文献

{"title":"Removal of dissolved arsenic from deep seawater around hydrothermal vents and seamounts","authors":"Yuanchen Li ,&nbsp;Guangyong Bo ,&nbsp;Yihua Cai ,&nbsp;Kan Zhang ,&nbsp;Kuanbo Zhou ,&nbsp;Pingping Zhang ,&nbsp;Chenjing Yang ,&nbsp;Tianyu Chen ,&nbsp;Minhan Dai ,&nbsp;Jian Ma ,&nbsp;Zhimian Cao","doi":"10.1016/j.epsl.2025.119351","DOIUrl":"10.1016/j.epsl.2025.119351","url":null,"abstract":"<div><div>Oceanic cycling of arsenic (As) is closely linked to that of nutrient and trace metal elements such as phosphorus (P) and iron (Fe), primarily due to similar particle-reactivity of As and P and their association with particulate carriers including Fe (oxyhydr)oxides. However, this particle scavenging effect is rarely reflected in seawater depth profiles of total dissolved inorganic As (DAs), which typically resemble those of nutrients, generally showing increasing concentrations with depth. Departing from conventional views, we observed distinct decreases in DAs concentration in deep waters around independent deep-sea systems in the subtropical western North Pacific: hydrothermal vents, seamounts, and island sediments. DAs removal corresponds to elevated dissolved and total dissolvable particulate Fe concentrations, indicating a major control of particle adsorption on As behavior in specific deep-ocean regions. Particle scavenging effect varied among the three deep-sea regions, mainly ascribed to varying particulate elemental compositions, and influence of temperature, pH, and dissolved oxygen. Our findings highlight a previously overlooked sink term for DAs removal from seawater by particles of various deep-sea origins. Newly estimated output fluxes around hydrothermal or seamount systems are comparable to the individual input flux from rivers, atmosphere, and hydrothermal vents, thus helping to balance the global oceanic As budget.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119351"},"PeriodicalIF":4.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828973","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 contribution of mechanoradical reactions to crustal hydrogen generation","authors":"Nicolas Lefeuvre ,&nbsp;Laurent Truche ,&nbsp;Frédéric-Victor Donzé ,&nbsp;Johan Vandenborre ,&nbsp;Eric C. Gaucher ,&nbsp;Valérie Magnin","doi":"10.1016/j.epsl.2025.119363","DOIUrl":"10.1016/j.epsl.2025.119363","url":null,"abstract":"<div><div>Hydrogen (H₂) generation within the Earth's crust contributes significantly to abiotic organic synthesis and the sustenance of deep microbial ecosystems. While natural H₂ is recognized as a potential primary energy resource, current exploration models focus solely on two sources, serpentinization and water radiolysis, leaving other H₂-generating processes largely unexplored. This study investigates mechanoradical reactions specifically, H₂ production resulting from mineral grinding in the presence of water, a process analogous to rock abrasion along fault planes during earthquakes. We performed laboratory experiments simulating these conditions by grinding quartz under controlled conditions of fluid pH, ionic strength, water/rock (W/R) ratio, and grinding energy. Our results show that H₂ production is significantly affected by these parameters. Notably, grinding in acidic environments (6&lt; pH &lt; 4) tripled H₂ production compared to alkaline conditions (pH &gt;8). Increasing the W/R ratio from 0.1 to 1 resulted in an 18-fold enhancement of H₂ production. Additionally, a linear relationship was observed between H₂ production and the grinding energy applied. Extrapolating our findings to natural fault movements, we estimate that mechanoradical reactions during earthquakes of magnitude greater than 4 generate approximately 1.45 <span><math><mo>×</mo></math></span> 10¹³ mol yr^-1 of H₂. Although this production rate involved significant incertainties related to the model assumptions and may not be directly compared to serpentinization and radiolysis - since these H₂-producing processes operate on different time and space scales - our study underscores the importance of including mechanoradical processes in models of crustal H₂ fluxes. Recognizing these reactions expands our understanding of subsurface H₂ generation and its contributions to geochemical and microbial processes in the Earth's crust.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119363"},"PeriodicalIF":4.8,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143823790","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":"Seismic azimuthal anisotropy of New Zealand revealed by adjoint-state traveltime tomography","authors":"Shucheng Wu ,&nbsp;Jing Chen ,&nbsp;Ping Tong","doi":"10.1016/j.epsl.2025.119362","DOIUrl":"10.1016/j.epsl.2025.119362","url":null,"abstract":"<div><div>The omission of seismic anisotropy in current reference models covering the entire New Zealand has been an obstacle to achieving a comprehensive understanding of deformation and dynamics along the complex Pacific-Australian plate boundary segment. Here we present a 3D azimuthally anisotropic model that encompasses both the North and South Islands of New Zealand to a depth of 40 km, using over 1 million local P-wave arrival times and a newly developed adjoint-state traveltime tomography technique. This model is built upon the New Zealand-wide 3D isotropic velocity model, serving as an essential and incremental update to the existing model. Our new model highlights significant variations in anisotropy across the plate boundary region, indicating distinct deformation states between tectonic blocks. In the North Island, pronounced along-strike changes in anisotropy are evident beneath the Hikurangi forearc, which could be attributed to variations in stress regime associated with the oblique plate convergence and changes in interseismic coupling of the subduction megathrust. The oblique plate motion further induces pure shear deformation in the middle to lower crust of the southern backarc, resulting in strong anisotropy with fast axes perpendicular to the principal axes of maximum horizontal compression. In contrast, seismic anisotropy in the central South Island primarily stems from the preferential alignment of minerals, notably within the Haast schist in the Otago block. However, anisotropy in the middle to lower crust of the northern South Island may represent inherited structures that originated during past southward subductions along the Gondwana margins at ∼100 Ma. Our new model offers valuable insights into the intricate geological processes occurring within the plate boundary region.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119362"},"PeriodicalIF":4.8,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143823794","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":"Volcanic CO2 emissions from subduction of the tropical Paleo-Tethyan Ocean contributed to the early Permian deglacial warming","authors":"Wei Feng ,&nbsp;Jianghai Yang ,&nbsp;Peter A. Cawood ,&nbsp;Rui Ma ,&nbsp;Yinsheng Zhou ,&nbsp;Ying Cui","doi":"10.1016/j.epsl.2025.119361","DOIUrl":"10.1016/j.epsl.2025.119361","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Subduction of oceanic crust is a critical tectonic process that controls the recycling of carbon from the lithosphere to the atmosphere through volcanism and thus influences the evolution of Earth's climate. However, the potential contribution of volcanic CO&lt;sub&gt;2&lt;/sub&gt; from arc systems to the long-term warming in the Paleozoic has not been quantified. The early Permian subduction zones of the eastern Paleo-Tethyan orogens formed in tropical latitudes. To evaluate the causal link between arc volcanic CO&lt;sub&gt;2&lt;/sub&gt; emissions and warming in the early Permian, we study the early Permian volcano-sedimentary successions in the Ailaoshan Belt of southwest China, which constitutes part of the eastern Paleo-Tethyan orogens. Volcanic rocks separating the lower and upper sedimentary units yield a zircon U-Pb age of 284 ± 2 Ma, and along with the youngest detrital zircon age group, determine an early Permian age (ca. 290−275 Ma) for the sampled successions. For the sedimentary rocks, abundant volcanic lithic fragments are observed and a predominant detrital zircon age group of 300−270 Ma is defined. Zircons of this age group can be classified into two geochemical types in terms of variations in trace element ratios and Hf isotopes. Combining with sandstone modal compositions, two types of volcanic source rocks that represent arc and back-arc volcanism are distinguished. These provenance data support a westward subduction model for the early Permian Paleo-Tethyan Ocean along the Ailaoshan Belt where subduction may have initiated in the late Carboniferous (ca. 320 Ma) and strengthened in the early Permian (ca. 295 Ma). Based on sedimentological, magmatic and structural correlations, the early Permian subduction zone in the Ailaoshan Belt can be extended to the north along the Jinshajiang Belt and to the south along the Song Chay and Song May belts, forming a ∼1700 km continental arc system, allowing the entire length of the tropical Paleo-Tethyan Ocean continental arc system to reach ∼6350 km. Peak volcanism from this arc system is concomitant with the early warming event at 290−280 Ma. Considering the prevailing carbonate deposition in the adjacent blocks, it is plausible to infer carbonate-rich sediments in these early Permian subduction zones because modern observations reveal high carbonate contents in the subducted sediments, which then generate high volcanic CO&lt;sub&gt;2&lt;/sub&gt; flux. Assuming the length-averaged volcanic CO&lt;sub&gt;2&lt;/sub&gt; emission rate (0.0018 – 0.0059 Mt yr&lt;sup&gt;−1&lt;/sup&gt; km&lt;sup&gt;−1&lt;/sup&gt;) based on modern tropical continental arc systems with carbonate-rich sediments on the down going plate, we find that the early Permian low latitude arc systems (∼6350 km) related to the subduction of eastern Paleo-Tethyan Ocean would have released ∼31,000 to 102,000 Gt C during the 10 Myr peak in volcanic activity. This volcanic CO&lt;sub&gt;2&lt;/sub&gt; degassing estimate is much higher than that (∼5300−17,800 Gt C) from the three Circum-Tethyan large igneous ","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119361"},"PeriodicalIF":4.8,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143823789","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":"Hypotheses for the water and metal fluxes to the rippled Amapari Marker Band, Gale Crater, Mars","authors":"E.S. Kite ,&nbsp;P. Gasda ,&nbsp;C.J. Tino ,&nbsp;C. Weitz ,&nbsp;L. Thompson ,&nbsp;B.M. Tutolo ,&nbsp;C.A. Mondro ,&nbsp;W.H. Farrand ,&nbsp;S. Gupta ,&nbsp;J. Schieber ,&nbsp;W.E. Dietrich ,&nbsp;N. Mangold ,&nbsp;K.W. Lewis ,&nbsp;R.S. Sletten","doi":"10.1016/j.epsl.2025.119347","DOIUrl":"10.1016/j.epsl.2025.119347","url":null,"abstract":"<div><div>Early Mars was habitable, at least intermittently, but major questions remain about how much water flowed and for how long. The paleoclimate evolution of Mars is captured by the stratigraphic record in Gale crater (Milliken et al. 2010). Climbing through mostly aeolian deposits reflecting arid conditions within Gale crater, the Mars Science Laboratory <em>Curiosity</em> rover encountered wave-rippled lake sediments of the basin-spanning Amapari Marker Band (AMB) that have very high metal enrichments (Fe, Mn, Zn). What caused the association between relatively wet primary depositional environment, and metal enrichment? Tentative, but reasonable extrapolation of rover metal data across the AMB suggests an excess Fe mass of 0.2 Gt. Transporting this Fe likely required ∼10,000 km³ of water flow, much more than the volume of the lake, across &gt;10³ yr. Deposition of the Fe could be due to a redox or pH front within or just beneath the lake. One possible basin-scale synthesis involves a climate excursion consisting of initial cooling then subsequent warming: initial cooling permits wind scour in Gale basin and ice build-up on Gale's rim, while subsequent melting fills the lake and mobilizes Fe. Alternatively, the data can be explained by water-table fluctuations. In either case, the metal enrichment likely contributed to the hardness of these rocks, aiding wave-ripple preservation.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119347"},"PeriodicalIF":4.8,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143817387","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":"Magmatic dikes in the Chang'e-6 sampling area","authors":"Qingyun Deng ,&nbsp;Zhiyong Xiao ,&nbsp;Yunhua Wu ,&nbsp;Pei Ma ,&nbsp;Wei Cao ,&nbsp;Yichen Wang ,&nbsp;Yizhen Ma ,&nbsp;Fanglu Luo ,&nbsp;Fei Li","doi":"10.1016/j.epsl.2025.119350","DOIUrl":"10.1016/j.epsl.2025.119350","url":null,"abstract":"<div><div>Volcanic deposits on the Moon are mainly distributed at the nearside but are rarer at the farside, and most farside mare are concentrated in the prominent South Pole-Aitken (SPA) basin. The asymmetric distribution of volcanic deposits is related to the fundamental characteristics of the Moon. The Chang'e-6 mission recently returned farside mare deposits from the Apollo basin in the SPA, which contain a wealth of information about the volcanic eruption mechanisms, magmatic processes, and mantle compositions of lunar farside. To assist ongoing sample analysis, we investigated magmatic dikes in the Apollo basin using the GRAIL gravity model. We detected 14 magmatic dikes that have a total length of ∼2200 km. The dikes exhibit circumferential distribution around the basin walls, some of which are spatially correlated with volcanic deposits and shallow intrusions visible at the surface, indicating that magma may have ascended along weakness planes formed by the Apollo basin. Volcanic deposits and shallow intrusive structures are not visible on the surface of most detected dikes, thus the ascending magma may have cooled as plutonic rocks. Root depths of the detected dikes are ∼37–49 km, which are not strictly correlated with their local crustal thicknesses, indicating that other factors in addition to lithostatic pressures affected magma ascending. The dikes beneath the Chang'e-6 landing mare have root depths of over 39 km, suggesting that partial melting occurred at greater depths that have pressures of excess ∼161 MPa. The estimated volume of plutonic rocks in these dikes is about 1.2 × 10⁴ km³, which is 15 times larger than that of the basaltic deposits in the landing mare.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119350"},"PeriodicalIF":4.8,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143817386","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":"Modeling earthquake-induced seiche processes and subsequent homogenite deposition in lacustrine settings","authors":"Muhammad Naveed Zafar ,&nbsp;Pierre Sabatier ,&nbsp;Denys Dutykh ,&nbsp;Hervé Jomard ,&nbsp;William Rapuc ,&nbsp;Patrick Lajeunesse ,&nbsp;Emmanuel Chapron","doi":"10.1016/j.epsl.2025.119348","DOIUrl":"10.1016/j.epsl.2025.119348","url":null,"abstract":"<div><div>Earthquakes leave distinct signatures on lake systems, including event deposits that serve as valuable paleoseismological archives. Among these deposits, homogenite layers are commonly associated with lake oscillations, i.e., seiches. Here, we investigate the seiche mechanism and the formation of a homogenite related sediment deposit within a lacustrine environment. This study focuses on the 1822 CE earthquake in the Western European Alps, which triggered subaqueous landslides in Lake Bourget (France). This event caused oscillations in the lake's water, which subsequently resulted in the formation of a homogenite layer in the deep basin. The underlying mechanism is resolved by presenting the first comprehensive numerical model via coupling of coseismic displacement, seismic wave propagation, and mass movement with the tsunami model. The numerical simulations show excellent agreement with the available geological and historical observations. The water disturbances caused by subaqueous landslides generated small tsunami waves with a maximum runup height of approximately 2.5 m. By analyzing the tsunami signals using Fourier spectral analysis and fast iterative filtering, we determined that seismic waves are the primary drivers of seiche, which excite the natural modes of Lake Bourget. Our numerical results confirm that the sediments found in the deep basin originated from one main subaqueous landslide and from tsunami erosion of littoral sands (backwash). However, the seismically induced seiche was solely responsible for keeping the fine-grained sediment cloud in suspension for several days and led to the formation of the homogenite layer (or seiche deposit) with typical grain orientation characteristics. The proposed numerical framework could also be effective in identifying whether landslides or delta collapses (linked to homogenite/megaturbidites) in closed lakes were triggered by seismic or nonseismic sources. This distinction is crucial for reconstructing the history of past earthquakes and associated hazards.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119348"},"PeriodicalIF":4.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143800456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stable tungsten (W) isotope systematics in marine sediments: a potential paleo-proxy for deep ocean oxygenation","authors":"Ruiyu Yang ,&nbsp;Marcus Gutjahr ,&nbsp;Florian Scholz ,&nbsp;Florian Kurzweil ,&nbsp;Sümeyya Eroglu ,&nbsp;Carsten Münker","doi":"10.1016/j.epsl.2025.119346","DOIUrl":"10.1016/j.epsl.2025.119346","url":null,"abstract":"<div><div>The stable tungsten (W) isotope system has emerged as a promising paleoenvironmental indicator. However, the modern oceanic budget of W and its behavior during sedimentary burial are to date not well understood. Specifically, the mechanisms governing W delivery to marine sediments and its behavior during early diagenesis remain unknown. In this study, we analyzed stable W isotopic compositions (δ^186/184W) in three sediment cores from various redox environments in the Gulf of California. Additionally, we investigated δ^186/184W compositions and major and trace elemental compositions in surface sediments from global ocean basins. Our findings indicate that continental margin sediments and hydrothermal precipitates lack significant authigenic W enrichment, whereas deep-ocean surface sediments exhibit notable W enrichment, primarily associated with Mn-oxides. Tungsten appears to be delivered alongside Mn but does not undergo burial under anoxic or euxinic conditions, unlike its geochemical counterpart, Mo. The tungsten output flux into total Mn oxides is estimated at 22.2 × 10⁶ mol/yr. Authigenic W (excess W relative to the detrital input) exhibits heavier W isotope compositions compared to equilibrium adsorption on Mn oxides from modern seawater, averaging a δ^186/184W of 0.255 ± 0.025 ‰. This is likely due to fractionation processes during continuous exchange between pore-water and the solid phase, or the recrystallization of Mn oxides during diagenesis. Finally, we propose an updated mass budget of W and its isotopes in the modern ocean suggesting that the benthic W recycling could be an important, so far underestimated source of W to the ocean. The exclusive association between W and Mn suggests that W isotopes could serve as a valuable indicator for identifying deep-ocean oxygenation in Earth's history. To advance this idea, further comprehensive investigations into W isotopic fractionation across various Fe and Mn oxide minerals, as well as additional downcore studies in authigenic W enriched pelagic core sites, would be essential.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119346"},"PeriodicalIF":4.8,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intense rift magmatism caused rapid thickening of Yilgarn Craton crust at 2.7 Ga","authors":"Alan R.A. Aitken,&nbsp;Q. Masurel,&nbsp;N. Thébaud,&nbsp;Lu Li,&nbsp;Abdul Azim bin Rossalim","doi":"10.1016/j.epsl.2025.119336","DOIUrl":"10.1016/j.epsl.2025.119336","url":null,"abstract":"<div><div>The crustal structure of many Archean cratons fits a paradigm of relatively thin crust (&lt; 35 km), with felsic compositions, low-velocity lower crust and a sharp Moho discontinuity. This contrasts with the crusts of Proterozoic regions, which are typified by thicker crust (&gt; 40 km), often with a high-velocity lower crust and a diffuse Moho. A global-scale transition in the nature of the crust is suggested, but its timing and nature remain unclear. The Yilgarn Craton in Western Australia has crustal thickness from ∼ 30 km to &gt; 45 km and may preserve a key example of this transition. This study employs seismic-constrained gravity inversion to resolve in detail the thickness and density of the Yilgarn Craton crust. Regions with thick and dense crust are identified, and we explore two scenarios for their development: scenario 1 involves crustal shortening, erosion, and the development of a garnet-bearing lower crust, and scenario 2 involves addition of mafic magmatic rocks during extension. Scenario 2 is more consistent with the Neoarchean geology of the craton and the inferred extents of juvenile magmatism between 2.73 to 2.65 Ga. A regional stratigraphic unconformity at ca. 2.73 Ga is recognised as a turning point in the evolution of the craton, marking the crossing of thermo-rheological thresholds for geodynamically-stable lower crust. We suggest that net crustal thickening occurred over the next ∼40 Ma with a mafic magmatic input totalling 5.0 Mkm³ balanced by moderate extension (β-factor ∼ 1.1) Monte-Carlo simulations use a time-and-space distributed series of events of &lt;40 Ma duration and &lt;10 MKm³ vol to successfully explain modelled variations in global average crustal thickness through time. The event identified here aligns with a peak in constructive tendency, supporting the diachronous and episodic growth of the global lower crust during the Neoarchean.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119336"},"PeriodicalIF":4.8,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct carbon sequestration in the glacial Pacific despite vigorous deep ocean circulation","authors":"Jinlong Du,&nbsp;Jun Tian","doi":"10.1016/j.epsl.2025.119344","DOIUrl":"10.1016/j.epsl.2025.119344","url":null,"abstract":"<div><div>The Pacific Ocean holds the largest marine carbon inventory and serves as a vital sink for atmospheric CO₂ during glacial periods. Associated with drastic cooling of the global oceans, the Pacific carbon sequestration has traditionally been attributed to slow deep circulation, similar to the mechanisms possibly occurring in the glacial Atlantic Ocean. Recently, however, this view has come under scrutiny due to a compilation of neodymium isotope records showing a shorter, rather than longer, transit time for deep Pacific water masses. The noted discrepancy suggests the presence of differing carbon dynamics operating in the glacial Pacific, raising the question of whether a larger carbon reservoir could persist under stronger deep ocean circulation. Here, we employ biogeochemical simulations to examine the possible mechanisms driving the enhanced carbon inventory in the glacial Pacific. The results indicate that the proposed rapid movement of deep Pacific water masses may be linked to cooling in the Southern Ocean, which further increases carbon storage primarily by intensifying air-sea disequilibrium at surface and impeding diapycnal mixing within the ocean interior. Essentially, the results suggest that a substantial Pacific carbon inventory can withstand intensified deep circulation. In the context of thermohaline circulation, the glacial North Atlantic plays a crucial role in absorbing atmospheric CO₂, whereas the surface Southern Ocean and North Pacific operate synergistically to inhibit the release of carbon from the ocean.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"660 ","pages":"Article 119344"},"PeriodicalIF":4.8,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777513","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}