-
Complex irradiation history of chondrules and matrix – A study of CR2 and some other meteorites Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-14 Uta Beyersdorf-Kuis, Ulrich Ott, Mario Trieloff
Excesses of cosmic-ray produced nuclei in individual components of meteorites indicate “pre-irradiation”, either in the surface region of their parent bodies or as free-floating small particles in the early Solar System. We expand on our earlier work (Beyersdorf-Kuis et al., 2015) and report a study of cosmic-ray produced He and Ne in chondrules and “matrix” (i.e., matrix-dominated) material of several
-
Investigation of hydrochemical characteristic, water quality and associated health risks of metals and metalloids in water resources in the vicinity of Akamkpa quarry district, southeastern, Nigeria Geochem. Trans. (IF 0.9) Pub Date : 2024-09-12 George E. Ikpi, Therese N. Nganje, Aniekan Edet, Christopher I. Adamu, Godswill A. Eyong
Quarrying of rock aggregates generates produced water that, if not handled properly will be a source of pollution for nearby water bodies, thus affecting the chemistry of the water. This study examined the chemistry, impact of quarrying activities on water resources and the health consequences/risks posed by ingestion of the water by humans in the Akamkpa quarry region in southeastern Nigeria. Thirty
-
Stable carbon isotope ratios of pristine carbohydrates preserved within nannofossil calcite Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-10 Harry-Luke Oliver McClelland, Renee B.Y. Lee, Ann Pearson, Rosalind E.M. Rickaby
The geochemical characterization of phytoplankton-derived organic compounds found in marine sediments has been widely used to reconstruct atmospheric pCO2 throughout the Cenozoic. This is possible owing to a well-established relationship between the carbon isotope ratios of phytoplankton biomass and CO2 concentration in the ambient seawater. An ideal molecular target for such proxy reconstructions
-
Thermodynamics and kinetics of cation partitioning between plagioclase and trachybasaltic melt in static and dynamic systems: A reassessment of the lattice strain and electrostatic energies of substitution Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-10 Silvio Mollo, Fabrizio Di Fiore, Alice MacDonald, Teresa Ubide, Alessio Pontesilli, Gabriele Giuliani, Alessandro Vona, Claudia Romano, Piergiorgio Scarlato
Most of the solidification history of magmas beneath active volcanoes takes place in chemically and physically perturbed plumbing systems where the growth of crystals is collectively governed by a range of kinetic processes related to the dynamics of crustal reservoirs and eruptive conduits. In this context, we have experimentally investigated the partitioning of major, minor, and trace cations between
-
Robust methods, tricky materials: Challenges in dating high common-Pb perovskite from Cretaceous Brazilian kimberlites Chem. Geol. (IF 3.6) Pub Date : 2024-09-10 R.G. Azzone, D.G. Pearson, C. Sarkar, L.M.T. Cetina, L. Chmyz, Y. Luo, E. Ruberti, V. Guarino, I. Cabral-Neto
Kimberlites and related rocks are the focus of research and exploration in the Alto Paranaiba Igneous Province (APIP; Brazil) due to their potential correlation with adjacent diamond fields. New U-Pb perovskite ages were obtained using recommended protocols for error propagation and data interpretation. Despite the utility of perovskites for dating, their incorporation of significant common-Pb (common-Pb
-
Absolute 230Th/U chronologies and Δ47 thermometry paleoclimate reconstruction from soil carbonates in Central Asian loess over the past 1 million years Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-07 Gábor Újvári, Ramona Schneider, Thomas Stevens, László Rinyu, Gabriella Ilona Kiss, Jan-Pieter Buylaert, Andrew Sean Murray, Amélie J.M. Challier, Redzhep Kurbanov, Farhad Khormali, Judit Benedek, Marjan Temovski, Danny Vargas, László Palcsu
Pleistocene loess records of the Khovaling Loess Plateau (KLP) in Tajikistan provide rich collections of lithic artifacts demonstrating past human presence in the region. To understand the timing of human activity and environmental conditions prevailing at that time U–Th dating and clumped/stable C/O isotope measurements have been applied to modern and Pleistocene soil carbonates (SCs) collected at
-
Systematic behaviour of 3He/4He in Earth’s continental mantle Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-07 S.A. Gibson, J.C. Crosby, J.A.F. Day, F.M. Stuart, L. DiNicola, T.R. Riley
Helium isotopes are unrivalled tracers of the origins of melts in the Earth’s convecting mantle but their role in determining melt contributions from the shallower and rigid lithospheric mantle is more ambiguous. We have acquired new 3He/4He data for olivine and pyroxene separates from 47 well-characterised mantle xenoliths from global on- and off-craton settings. When combined with existing data they
-
Organic matter the major sink of redox-sensitive trace elements in Upper Devonian black shale Chem. Geol. (IF 3.6) Pub Date : 2024-09-06 Omid H. Ardakani, Michael G. Gadd, Makram Hedhli, Duane Petts, Gavin Jensen
The Bakken Formation is a hydrocarbon-rich, metalliferous shale with subordinate sandstone and limestone that was deposited in the Williston Basin in Canada and the USA. Deposition of the Bakken Formation spanned the Devonian-Carboniferous boundary – a key interval in Earth's history representing profound biotic and geochemical changes in the terrestrial and marine realms, leading to deposition of
-
In situ Lu–Hf dating of allanite by LA-ICP-MS/MS: Implications for geochronology Chem. Geol. (IF 3.6) Pub Date : 2024-09-05 Shitou Wu, Yueheng Yang, Hao Wang, Nick M.W. Roberts, Junlong Niu, Yijia Wang, Jinhui Yang, Fuyuan Wu
Allanite is a common REE-rich accessory mineral found in various igneous and metamorphic rocks, and can record a variety of geological processes. Therefore, allanite geochronology has the potential to answer a range of important geological questions. Allanite U–Th–Pb geochronology is hampered by common open-system behavior in the system. In this study, we demonstrate the feasibility of allanite Lu–Hf
-
Carbonate clumped isotope values compromised by nitrate-derived NO2 interferent Chem. Geol. (IF 3.6) Pub Date : 2024-09-05 Jens Fiebig, Miguel Bernecker, Niels Meijer, Katharina Methner, Philip Tauxe Staudigel, Amelia Jane Davies, Lkhamsuren Bayarjargal, Dominik Spahr, Björn Winkler, Sven Hofmann, Manuel Granzin, Sierra V. Petersen
based clumped isotope thermometry has enabled reconstruction of Earth's surface temperatures independent of the source of oxygen within the carbonate. It has been postulated that carbonate samples can contain contaminants that cause isobaric interferences, compromising measured values and reconstructed temperatures. The exact nature of contaminants and isobaric interferents, however, largely remained
-
A petrogenetic study of apatite in Chang’E-5 basalt: Implications for high sulfur contents in lunar apatite and volatile estimations for the lunar mantle Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-04 Huijuan Li, Zilong Wang, Zhenyu Chen, Wei Tian, Wei-(RZ) Wang, Guibin Zhang, Lifei Zhang
Apatite is ubiquitous in lunar samples and has been used widely for estimating volatile abundances in the lunar interior. However, apatite compositional and isotopic variations within and between samples have resulted in varying and ambiguous results. Understanding apatite petrogenesis will help with both identifying the appropriate composition for volatile estimation and interpreting isotopic variations
-
Grossite-bearing refractory inclusions from reduced CV chondrites: Mineralogical and oxygen isotopic constraints on the parent body alteration history Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-04 Jangmi Han, Kazuhide Nagashima, Changkun Park, Alexander N. Krot, Lindsay P. Keller
We report the results of coordinated mineralogical, microstructural, and oxygen isotopic analyses of grossite-bearing refractory inclusions from reduced CV (Vigarano type) chondrites to obtain a more complete picture of secondary parent body alteration processes and conditions. Grossite (CaAl4O7) occurs in cores of nodules in fine-grained Ca,Al-rich inclusions (CAIs) that likely represent aggregates
-
The last generation of nebular chondrules possibly sampled in the CH/CBb chondrite Isheyevo Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-04 Timothé Mahlé, Yves Marrocchi, Julia Neukampf, Johan Villeneuve, Emmanuel Jacquet
Among carbonaceous chondrites, the chondrules of CB and CH stand out by being dominated by skeletal barred olivine and cryptocrystalline textures. These non-porphyritic chondrules are thought to have formed within an impact-generated plume resulting from large-scale asteroidal collisions late in disk history. Porphyritic chondrules are also present, if rare, in CB and CH chondrites and might correspond
-
Re-evaluating the diffusivity of phosphorus in olivine: Implications of low diffusive mobility for thermochronology Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-03 William Nelson, Julia Hammer, Thomas Shea
Heterogeneities in the phosphorus (P) content of olivine are relatively resistant to diffusive homogenization when compared with other compositional heterogeneities. Thus, heterogeneities in the spatial distribution of P can preserve petrological information about olivine crystals from the earliest stages of crystallization which have been otherwise eliminated. However, compared to independent determinations
-
Transition metals in alkaline Lost City vent fluids are sufficient for early-life metabolisms Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-02 Guy N. Evans, Shichao Ji, Betül Kaçar, Ariel D. Anbar, William E. Seyfried Jr.
Despite the importance of alkaline seafloor hydrothermal vents in broadening our understanding of deep-sea hydrothermal ecosystems, little is known about the mobility and concentrations of micronutrient transition metals in these environments. Here, we present new analyses of micronutrient transition metal concentrations in vent fluids from the iconic Lost City Hydrothermal Field (LCHF) and report
-
Detrital K-feldspar as a novel archive of continental crustal evolution using coupled in situ Rb[sbnd]Sr dating and Pb isotope analysis Chem. Geol. (IF 3.6) Pub Date : 2024-09-02 Dan Bevan, Daniel Stubbs, Christopher D. Coath, Jamie Lewis, Tim Elliott
Here we present RbSr and Pb isotopic analysis of K-feldspar from the Shap Granite, (Cumbria, UK) and detrital K-feldspar from the associated Shap Wells Conglomerate Formation, to investigate the potential of the detrital K-feldspar record as an archive of crustal composition. We use a unique, collision cell – multi collector inductively coupled plasma tandem mass spectrometer to make the isotope measurements
-
Ebullition drives high methane emissions from a eutrophic coastal basin Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-01 Olga M. Żygadłowska, Jessica Venetz, Wytze K. Lenstra, Niels A.G.M. van Helmond, Robin Klomp, Thomas Röckmann, Annelies J. Veraart, Mike S.M. Jetten, Caroline P. Slomp
The production of methane in coastal sediments and its release to the water column is intensified by anthropogenic eutrophication and bottom water hypoxia, and it is still uncertain whether methane emissions to the atmosphere will be enhanced. Here, we assess seasonal variations in methane dynamics in a eutrophic, seasonally euxinic coastal basin (Scharendijke, Lake Grevelingen). In-situ benthic chamber
-
Intrasample osmium isotope disequilibrium in young volcanic rocks: Insights from a new progressive digestion procedure Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-09-01 Siddhartha Bharadwaj, Mukul Sharma
Some young volcanic rocks have been found to possess intrasample Os-isotope heterogeneity. This has important implications for source tracing and dating. Here, we use a new procedure through which it is possible to sequentially extract, from a single aliquot, the Os/Os ratio of: i) the surface contaminant(s) (hydrobromic acid leachate); ii) the residual bulk rock powder (Step I) and iii) the Os-bearing
-
Seawater-oceanic crust interaction constrained by triple oxygen and hydrogen isotopes in rocks from the Saglek-Hebron complex, NE Canada: Implications for moderately low-δ18O Eoarchean Ocean Chem. Geol. (IF 3.6) Pub Date : 2024-09-01 A. Kutyrev, I.N. Bindeman, J. O'Neil, H. Rizo
Estimations of Earth's earliest surface conditions assume a strong connection between the temperature and oxygen isotopic composition of oceans, balanced by surface weathering and submarine hydrothermal alteration. The oldest preserved supracrustal rocks provide rare opportunities to study and constrain the earliest surface conditions prevailing on the Earth. Here, we present a study of triple oxygen
-
Uptake time and enrichment mechanism of rare earth elements in deep-sea bioapatite Chem. Geol. (IF 3.6) Pub Date : 2024-09-01 Yonghang Xu, Dongyi Li, Yang Alexandra Yang, Jian Chen, Siyu Zhao, Louwang Yan, Xijie Yin, Fanyu Lin, Yunhai Li, Feng Wang
Bioapatite is widely recognized as the primary carrier for rare earth elements and yttrium (REY) in deep-sea REY-rich muds. The incorporation of REY into bioapatite occurs at the water-sediment interface, which has the potential to serve as a proxy for reconstructing paleoenvironmental conditions. The timing of REY uptake and the fractionation of rare earth elements (REEs) within bioapatite are crucial
-
Theoretical and experimental constraints on hydrogen isotope equilibrium in C1-C5 alkanes Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-31 Hao Xie, Michael J. Formolo, Alex L. Sessions, John M. Eiler
Stable isotope ratios of C1–C5 alkanes, the major constituents of subsurface gaseous hydrocarbons, can provide valuable insights on their origins, transport, and fates. Equilibrium isotope effects are fundamental to interpreting stable isotope signatures, as recognition of them in natural materials indicates reversible processes and constrains the temperatures of equilibrated systems. Hydrogen isotope
-
Gold in sulfide fluids revisited Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-31 Boris R. Tagirov, Nikolay N. Akinfiev, Mariia E. Tarnopolskaia, Irina Yu. Nikolaeva, Irina Yu. Zlivko, Valentina A. Volchenkova, Luydmila A. Koroleva, Alexander V. Zotov
Gold solubility was measured at temperatures of 350, 400, 450, and 490 °C and pressures of 500 and 1000 bar in an ’oxidized sulfide’ system, as a function of pHT (2 – 10) and sulfur concentration (m(Stotal) = 0.03 – 1.2 [mol·(kg H2O)-1]). In this system, sulfur primarily exists as H2S, H2SO3, H2SO4, their dissociation products, and radical species such as S2- and S3-. The complexes Au(HS)2-, Au2S22-
-
Microbial nitrogen transformations in tundra soil depend on interactive effects of seasonality and plant functional types Biogeochemistry (IF 3.9) Pub Date : 2024-08-30 Marianne Koranda, Anders Michelsen
-
Experimental constraints on barium isotope fractionation during adsorption–desorption reactions: Implications for weathering and erosion tracer applications Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-30 Alasdair C.G. Knight, Edward T. Tipper, Harold J. Bradbury, Alexandra V. Turchyn, Christoff Andermann, Heye Freymuth, Tim Elliott, Luke Bridgestock
Constraining the processes that fractionate barium isotopes is essential for utilising barium isotope ratios as environmental tracers. Barium concentration measurements from soils, rivers, and estuaries demonstrate that adsorption–desorption reactions significantly influence the distribution of fluid–mobile barium at the Earth’s surface, potentially driving isotopic fractionation. To quantify the direction
-
Tracing the orogenic sulfur cycle in the Andes using stable isotope composition of dissolved sulfate in thermal springs Chem. Geol. (IF 3.6) Pub Date : 2024-08-30 Tyler A. Grambling, Dennis L. Newell, Karen G. Lloyd, Coleman D. Hiett, Heather Upin, Peter H. Barry, Donato Giovannelli, J. Maarten de Moor, Agostina Chiodi, Gerdhard L. Jessen, Jenny M. Blamey, Anna Szynkiewicz
The cycling of sulfur (S) to the upper crust and surface via thermal springs at convergent margins has not been explored outside areas with active arc volcanism, even though subduction plays a key role in the Earth's long-term S cycle. To address this knowledge gap, we analyzed stable sulfur and oxygen isotope compositions (δS and δO values) of dissolved sulfate (SO) in 55 thermal springs from five
-
Intense intrusion of low-oxygen waters into mid-Cambrian surface ocean carbonate factories Chem. Geol. (IF 3.6) Pub Date : 2024-08-30 Yang-fan Li, Fei Li, Gregory E. Webb, Jitao Chen
The Phanerozoic surface ocean is characterized by its high dissolved oxygen content owing to mixing with the atmosphere. However, atmospheric oxygen levels varied in the early Paleozoic and it remains unclear whether the surface ocean was susceptible to significant redox fluctuations in response to extreme environmental events. In this study, we probed the redox structures of shallow middle Cambrian
-
Tourmaline composition probes serpentinite-derived fluid mobility in subduction zones Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-29 Jia-Wei Xiong, Yi-Xiang Chen, Attila Demény, Yong-Fei Zheng, Jan C.M. De Hoog, Guo-Chao Sun
Serpentinite dehydration in subduction zones plays a pivotal role in geochemical cycling on Earth. A number of geochemical studies on arc magmas have elucidated the contributions of serpentinite-derived fluids to mantle sources. However, due to complex geological overprints during subduction zone processes, discerning serpentinite signatures in exposed metamorphic rocks within fossil subduction zones
-
A review of the major chemical and isotopic characteristics of groundwater in crystalline rocks of the Canadian Shield Chem. Geol. (IF 3.6) Pub Date : 2024-08-29 Lamine Boumaiza, Randy Stotler, Shaun Frape
Canadian Shield groundwater characterization studies have been conducted over the last four decades through operating mines, underground research areas, and wells installed for a variety of purposes. A newly available database containing chemical and isotopic analytical results of groundwaters includes data from all of these sources and spans the Canadian Shield. The Precambrian Canadian Shield Groundwater
-
Short-term warming decreased soil DOM content and microbial species in alpine wetlands but increased soil DOM content and hydrolase activity in alpine meadows on the Tibetan Plateau Biogeochemistry (IF 3.9) Pub Date : 2024-08-27 Shiyu Fan, Jihong Qin, Hui Sun, Zhenchu Dan, Wenqing Chen, Jiyuan Yang
-
Hydrothermal alteration processes in monzogranite: a case study from the Eastern Desert of Egypt: implications from remote sensing, geochemistry and mineralogy Geochem. Trans. (IF 0.9) Pub Date : 2024-08-27 Amira M. El Tohamy
The South Eastern Desert (SED) of Egypt is one of the most promising areas in Egypt; it is widely explored for exploring the rare earth elements (REEs) and uranium-bearing ores. It is a main part of the Arabian-Nubian Shield (ANS). Therefore, the present study concerns with Sikait-Nugrus area as one of the most prolific sites in this region. The study provides a detailed geological, structural, and
-
Apatite and pyroxene as records of magmatic–hydrothermal processes and platinum-group mineral (PGM) formation in the Wengeqi mafic–ultramafic intrusion, Inner Mongolia, China: The role of oxidized, H2O-rich magmas Chem. Geol. (IF 3.6) Pub Date : 2024-08-28 Yonghua Cao, Luqing Zhou, Matthew Brzozowski, Christina Yan Wang
The Devonian Wengeqi mafic–ultramafic intrusion, situated on the northern margin of the North China Craton (NCC) — an Andean-style convergent margin during the Paleozoic — hosts many platinum-group minerals (PGMs), especially within the S-deficient, magnetite-rich clinopyroxenite zones. These PGMs occur in two distinct associations: Pt-rich PGMs (e.g., sperrylite) closely associated with primary magnetite
-
Collaborating iron and manganese for enhancing stability of natural arsenic sinks in groundwater: Current knowledge and future perspectives Chem. Geol. (IF 3.6) Pub Date : 2024-08-28 Xinxin Zhao, Zuoming Xie, Ruoqi Qiu, Weikang Peng, Fanfan Ju, Feng Zhong
Arsenic (As)-rich groundwater poses a serious threat to human life and public environmental safety. In groundwater environments, iron–manganese minerals (FeMn minerals) are widely distributed and have outstanding adsorption and oxidation abilities for many toxic metal ions, making them important heavy metal scavengers. Exploring the application of Nature-based Solutions (NBS) to enhance the natural
-
Efficient segregation of high-silica granitic melt from complementary cumulate caused by high-temperature gas sparging from mafic recharge Chem. Geol. (IF 3.6) Pub Date : 2024-08-28 Yifei Liu, Leon Bagas, Sihong Jiang, Fengxiang Wang
Segregation of granitic melts from their reservoir is a key process in the genesis of granites. However, the melt segregation mechanism is still enigmatic because the ability for the segregation of the melts from their magma reservoir decreases with decreasing temperature. Two complementary lithologic units have been identified in the Beidashan pluton of NE China, based on reverse mineral zoning, rimward
-
Detrital monazite evidence for crustal evolution of the North and South American continents during the Boring Billion Chem. Geol. (IF 3.6) Pub Date : 2024-08-28 Keita Itano, Kazumi Yoshiya, Shigenori Maruyama, Tsuyoshi Iizuka
Orogenic processes associated with the supercontinent cycle play crucial roles in the evolution of continental crust and surface environments. Detrital zircon records, useful archives of orogenic history, have recently suggested the possibility of orogenic quiescence during the Mesoproterozoic, the so-called . However, detrital zircon may not always provide a precise record of crustal evolution due
-
Testing triple oxygen isotope preservation in the new OPEnS totalizer against conventional monthly rainfall collectors Chem. Geol. (IF 3.6) Pub Date : 2024-08-28 L. Nicole Arellano, Emily J. Beverly, John S. Selker, Mitchell Nelke, Gurpreet Singh, Cara Walter
Understanding the mechanisms that drive spatial and temporal triple oxygen isotope (Δ′O) variations in modern precipitation is the first step to expanding the utility of these measurements as an environmental tracer jointly with traditional stable isotope parameters δD, δO, and d-excess. However, “totalizers” designed to collect a single precipitation sample pooled over a calendar month and minimize
-
Deciphering the transfer of hydroclimate signals to tree-ring δ18O using a proxy system model in East Asia's Meiyu region Chem. Geol. (IF 3.6) Pub Date : 2024-08-28 Yesi Zhao, Huayu Lu, Keyan Fang, Peng Zhang, Deliang Chen, Achim Bräuning, Jussi Grießinger, Bao Yang, Chenghong Liang, Hongyan Zhang, Yiqian Sun, Qing Jin, Jiarui Li, Xinsheng Liu
The stable oxygen isotope ratios of whole tree-ring α-cellulose (δO) have been interpreted as an indicator of early summer hydroclimate in the Meiyu region of East Asia. However, the underlying physical mechanism often remains unclear. Here we provide a mechanistic understanding through intra-annual tree-ring oxygen isotope analysis and process-based δO modelling over the period 1979–2006. The selected
-
Effects of mineral adsorption on the molecular composition of soil dissolved organic matter: Evidence from spectral analyses Chem. Geol. (IF 3.6) Pub Date : 2024-08-27 Xiaowen Li, Jian Yang, Chunzhao Chen, Anssi V. Vähätalo, Gunnhild Riise, Changqing Liu, Yihua Xiao
The adsorption of soil dissolved organic matter (DOM) by minerals is crucial for long-term carbon storage and has been extensively studied. However, the variations in soil DOM composition resulting from adsorption by different minerals have rarely been investigated from a spectral perspective. This study examined the impact of non‑iron (kaolinite) and iron-bearing (ferrihydrite) minerals on the concentration
-
Multiple effects of iron oxides on the adsorption and oxidation of dissolved organic matter by manganese oxides Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-25 Zecong Ding, Shiwen Hu, Lanlan Zhu, Jiang Xiao, Qianting Ye, Tongxu Liu, Zhenqing Shi
Adsorptive fractionation and oxidation of dissolved organic matter (DOM) on manganese (Mn) oxide surfaces alter the molecular composition and stability of DOM, but the impact of iron (Fe) oxides on the coupled adsorption-oxidation processes of DOM by Mn oxides is largely unknown. In this study, the underlying mechanisms of molecular transformation of DOM on birnessite (Bir) in the presence of ferrihydrite
-
Redox conditions influence the chemical composition of iron-associated organic carbon in boreal lake sediments: A synchrotron-based NEXAFS study Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-25 Andrew Barber, Yeganeh Mirzaei, Jay Brandes, Azadeh Joshani, Charles Gobeil, Yves Gélinas
The global carbon and iron cycles are intimately linked as redox-sensitive iron oxides readily bind organic carbon in a variety of environmental settings, including marine and lacustrine sediments. While these iron-organic carbon complexes sequester vast quantities of organic carbon, the composition of the organic matter within them remains unknown for lacustrine environments. Here we present C K and
-
Molybdenum isotope evidence for recycled oceanic crust in the mantle sources of continental intraplate mafic lavas, Emeishan Large Igneous Province Chem. Geol. (IF 3.6) Pub Date : 2024-08-24 Jiyong Li, Yi Liu, Shuo Chen
The chemical and lithological heterogeneities of Earth's mantle in oceanic settings have long been attributed to the presence of recycled materials such as subducted crust, oceanic or subcontinental lithosphere mantle and sediment, as evidenced by Mid-Ocean Ridge Basalts (MORB) and Ocean Island Basalts (OIB). However, the extent to which recycled materials contribute to mantle heterogeneity in continental
-
Seasonal patterns in riverine carbon form and export from a temperate forested watershed in Southeast Alaska Biogeochemistry (IF 3.9) Pub Date : 2024-08-23 Claire Delbecq, Jason B. Fellman, J. Ryan Bellmore, Emily J. Whitney, Eran Hood, Kevin Fitzgerald, Jeffrey A. Falke
-
Functional attributes of conifers expanding into temperate semi-arid grasslands modulate carbon and nitrogen fluxes in response to prescribed fire Biogeochemistry (IF 3.9) Pub Date : 2024-08-23 Justin D. Gay, Bryce Currey, Kimberley T. Davis, E. N. Jack Brookshire
-
Helium and carbon isotope compositions of thermal fluids in the northeastern Anatolia: Implications for the heat source and volatile flux Chem. Geol. (IF 3.6) Pub Date : 2024-08-23 Harun Aydin, Hüseyin Karakuş, Halim Mutlu, Nilgün Güleç
In this study, we make a quantitative assessment on the volatile flux of mantle-derived fluids and source of volatiles to explain the geologic controls on the transport of volatiles within thermal fluids of northeastern Anatolia. In line with this objective, we collected 22 samples (gas and water phase) from 16 geothermal fields in NE Turkey covering an area of nearly 100,000 km that extends from the
-
Partitioning denitrification pathways in N2O emissions from re-flooded dry paddy soils Biogeochemistry (IF 3.9) Pub Date : 2024-08-22 Yijia Tang, Budiman Minasny, Alex McBratney
-
Corrigendum to “Lipid composition, caloric content, and novel oxidation products from microbial communities within seasonal pack ice cores” [Geochimica et Cosmochimica Acta 368 (2024) 12–23] Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-22 Henry C. Holm, Helen F. Fredricks, Shavonna M. Bent, Daniel P. Lowenstein, Kharis R. Schrage, Benjamin A.S. Van Mooy
-
Copper isotope fractionation during magmatic evolution in a convergent tectonic setting: Constraints from sulfide Cu-S isotopes and whole-rock PGE of the Xiarihamu Ni-Cu sulfide deposit Chem. Geol. (IF 3.6) Pub Date : 2024-08-22 Qingyan Tang, Jian Bao, Yan Zhang, Zhuoming Li, Chi Zhao, Wei Liu, Lu Li
Nickel and cobalt are potentially critical metals in many countries because of their great significance for national security and economic development, and they are mainly derived from magmatic Ni-Cu‑platinum-group element (PGE) sulfide ore deposits hosted in mafic-ultramafic intrusions. Although Cu isotopes have been used to trace the metallogenic processes in Ni-Cu-(PGE) sulfide deposits, the Cu
-
Evaporite sequences as archives for Mg isotope compositions of seawater - Evidence from a Tethys marginal shelf basin in the Anisian Chem. Geol. (IF 3.6) Pub Date : 2024-08-22 Zhongya Hu, Weiqiang Li, Simon V. Hohl, Patrick Meister, Shouye Yang, Bolin Zhang, Zhiguang Xia, Chuan Liu
Evaporites have recently been suggested as a potential archive for recording the Mg isotope compositions (δMg) of coeval seawater. However, episodic dolomitization during the deposition of massive evaporites could cause considerable Mg removal and isotopic fractionation. To constrain the hydrological changes and influence of dolomitization on ambient brine δMg, we present petrographic and mineralogical
-
Environmental co-limitation on temperature responses of greenhouse gas production in floodplain sediments Biogeochemistry (IF 3.9) Pub Date : 2024-08-21 Maidina Zhumabieke, Jinhee Huh, Hyunji Lee, Ji-Hyung Park
-
The influence of mixing on seasonal carbon dioxide and methane fluxes in ponds Biogeochemistry (IF 3.9) Pub Date : 2024-08-21 Joseph S. Rabaey, James B. Cotner
-
Adsorption pathways of boron on clay and their implications for boron cycling on land and in the ocean Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-21 Simon J. Ring, Michael J. Henehan, Roberts Blukis, Friedhelm von Blanckenburg
Reversible adsorption and isotope fractionation of boron on the surface of clay minerals is a key process that impacts boron isotope cycling in porewater, rivers and the ocean. However, the differences in boron isotope fractionation factors between various clay minerals and their dependence on fluid chemistry are not well known. We performed two sets of experiments, using solutions of pure water with
-
Decoupling of dissolved organic carbon (DOC) and dissolved black carbon (DBC) in a temperate fluvial network Biogeochemistry (IF 3.9) Pub Date : 2024-08-19 Adrian M. Bass, Chao Gu
-
Phosphorus inactivation mitigates the effect of warm winters in a temperate shallow lake (Mielenko Lake, Poland) Biogeochemistry (IF 3.9) Pub Date : 2024-08-19 Renata Augustyniak-Tunowska, Rafał Karczmarczyk, Jolanta Grochowska, Michał Łopata, Agnieszka Napiórkowska-Krzebietke, Miquel Lürling
-
Lessons from lipid biomarkers preserved in methane-seep carbonates from the early Permian of Western Australia Chem. Geol. (IF 3.6) Pub Date : 2024-08-19 Siyu Wang, Daniel Birgel, Nicola Krake, Chuanbo Shen, David W. Haig, Jörn Peckmann
Sulfate-driven anaerobic oxidation of methane (SD-AOM) is the key biogeochemical process at marine seeps, seafloor environments sustaining lush chemosynthesis-based life. While an extensive molecular record of SD-AOM has been established for Cenozoic and Mesozoic seeps, to date only one reported case of SD-AOM exists for the Paleozoic. To get new insight into the dominant biogeochemical processes at
-
Update on the 53Mn-53Cr ages of dolomite in the Ivuna CI chondrite and asteroid Ryugu sample Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-18 Shingo Sugawara, Wataru Fujiya, Noriyuki Kawasaki, Naoya Sakamoto, Akira Yamaguchi, Hisayoshi Yurimoto
Aqueous alteration in planetesimals is one of the earliest geological processes in the solar system. The timing of aqueous alteration sheds light on the timescale of material evolution through water–rock interaction in small bodies. The Mn-Cr decay system, where a short-lived radionuclide Mn decays to Cr with a half-life of 3.7 Myr, is a powerful tool for dating carbonates in primitive meteorites that
-
HIDALGO: A FUN object from the earliest epoch of the solar system’s history Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-17 Ming-Chang Liu, Nozomi Matsuda, Kevin D. McKeegan, Emilie T. Dunham, Kaitlyn A. McCain
Chemical and isotopic measurements of HIDALGO, a stoichiometrically pure hibonite inclusion found in the matrix of the Dar al Gani 027 meteorite, were conducted by secondary ion mass spectrometry to investigate its origin and evolution. HIDALGO is characterized by large mass-dependent isotope fractionations in O, Ca, and Ti, as well as large negative anomalies in neutron-rich Ca and Ti, making it the
-
Dominant host phase of mercury within the sediments of the East China Sea inner shelf: Implications for mercury inputs Chem. Geol. (IF 3.6) Pub Date : 2024-08-17 Xin Chang, Xiting Liu, Kaidi Zhang, Anchun Li, Limin Hu, Mingyu Zhang, Houjie Wang, Guangchao Zhuang, Jun Shen
Mercury (Hg) concentrations normalized to their dominant hosts have been widely used to identify geological events such as massive volcanic eruptions. However, the modern Hg cycle has significantly changed, and the implications of host-normalized Hg concentrations for the Hg dynamics in contemporary coastal environments (e.g., sources, delivery mechanisms, and Hg fluxes) remain poorly understood. In
-
Evaluating intragrain gradients in the δ34S of pyrite using a 7f-GEO SIMS Chem. Geol. (IF 3.6) Pub Date : 2024-08-15 Jennifer L. Houghton, Clive Jones, David A. Fike
Recent work has highlighted the need to distinguish the contribution(s) of different populations of petrographically and isotopically distinct pyrites to interpret bulk δS sedimentary values. To address this, we developed a method for micron-scale isotopic characterization of petrographically diverse sedimentary pyrites within a multimineralic matrix using ion imaging with a 7f-GEO secondary ion mass
-
Nitrate and silicate fluxes at the sediment–water interface of the deep North Pacific Ocean illuminated by 226Ra/230Th disequilibria Geochim. Cosmochim. Acta (IF 4.5) Pub Date : 2024-08-14 Yilin Cheng, Pinghe Cai, Hongyu Chen, Liuting Yuan, Xinyu Jiang, Shengai Zhang, Yaojin Chen, Yiming Luo, Yoshiki Sohrin
By taking advantage of recent analytical advances, we herein develop the Ra/Th isotope systematics as a novel tool for quantifying nitrate and dissolved silicate fluxes across the sediment–water interface of the deep-ocean floor. Sediment cores were retrieved from the seabed between 4927 m and 5951 m in the North Pacific Ocean. Downcore profiles of Th and both dissolved and total Ra were measured using
-
Rhenium–Os isotopic systematics of late Cenozoic intraplate basaltic rocks from Korea: Implications for recycled slab materials in their mantle source Chem. Geol. (IF 3.6) Pub Date : 2024-08-14 Sung Hi Choi, Katsuhiko Suzuki, Ryoko Senda
We present, for the first time, comprehensive Re-Os isotopic data for 23 late Cenozoic intraplate basaltic rocks from seven locations (Mount Baekdu, Jeongok, Baengnyeong Island, Ganseong, Ullueng Island, Dok Island, and Jeju Island) on the Korean Peninsula. The Re-Os isotopic system serves as an important tracer of processes such as the reworking of old continental lithosphere or the deep crustal recycling
-
Exploring intrusive processes through the crystal cargo of volcanic rocks: The case of lava flows from Taranaki volcano, New Zealand Chem. Geol. (IF 3.6) Pub Date : 2024-08-14 Nessa G. D'Mello, Georg F. Zellmer, Teresa Ubide, John Caulfield, Masako Usuki, Yoshiyuki Iizuka, Gabor Kereszturi, Jon N. Procter, Robert B. Stewart
The present-day edifice of Taranaki volcano, New Zealand, is largely made up of lava flows extruded over approximately the last 8 kyr. The crystal cargo of plagioclase, pyroxene and amphibole in these lavas displays varied major, minor, and trace element zoning patterns, pointing to long and complex crystal growth histories. Crystal zoning patterns do not vary systematically between stratigraphic units