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Arc building and maturation of the Lombok Island, East Sunda Arc Chem. Geol. (IF 3.6) Pub Date : 2024-07-06 Guo-Rong Tang, Wei Dan, Adi Maulana, Jian Wang, Xiu-Zheng Zhang, Yun-Ying Zhang, Xin Ma, Qiang Wang, Xi-Jun Liu, Gong-Jian Tang
Intra-oceanic subduction zones are major sites of crust–mantle material exchange and crustal growth; however, the processes responsible for the magmatic evolution and transformation of nascent arcs into mature oceanic arcs with thicker crust are debated. We present mineral chemistry, zircon UPb age and Hf isotopic data, and whole-rock chemical and Sr–Nd–Hf–Pb isotopic data for Cenozoic volcanic rocks
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Thermal evolution of the North China Craton revealed by microsampling garnet geochronology on single xenoliths Chem. Geol. (IF 3.6) Pub Date : 2024-07-06 Kai-Yang Du, Hao Cheng, Ruyi Yang
Granulite xenoliths, sourced from the lower cratonic crust and brought to the Earth's surface within volcanic rocks, offer unique insights into the formation and destruction of cratons. Age determinations are essential for constructing the thermal history of cratons. However, accurate dating is complicated by the xenoliths' extended exposure to high temperatures and their complex thermal histories
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Indigenous microbial influence on REE enrichment and fractionation in South China weathering crusts: Insights from experimental simulations Chem. Geol. (IF 3.6) Pub Date : 2024-07-05 Xurui Li, Lingya Ma, Yilin He, Xiaoliang Liang, Jianxi Zhu, Hongping He
The activity of microorganism plays an important role on the enrichment, migration and fractionation of rare earth elements (REEs) in the supergene environment. To investigate the characteristics of indigenous microorganisms on the enrichment and fractionation of REEs, we studied the adsorption efficiencies of REEs by 30 indigenous microbial strains that were isolated and cultured from the weathering
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Composition effects on equilibrium oxygen isotope fractionation factors between garnets and quartz/calcite/olivine: Implication from vibration frequencies of garnets at high temperatures and high pressures Chem. Geol. (IF 3.6) Pub Date : 2024-07-03 Xi Zhu, Guangchen Chen, Yu Ye, Zhengrong Wang, Wei Du, Qingbo Wang, Sha Wang, Yancheng Hu, Yunfan Miao, Zhen Wu, Dan Liu
Garnet-group minerals, with their wide range of compositions, play a significant role in Earth's crust and upper mantle, participating in various petrological and geochemical processes. Oxygen isotope fractionation factors between garnets and other minerals hold crucial implications in these contexts. In this work, vibration frequencies were measured via Raman spectra on five garnet mineral samples
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Magnesium isotope fractionation during magmatic differentiation in the lower continental crust Chem. Geol. (IF 3.6) Pub Date : 2024-07-03 Ying Wei, Xiao-Long Huang, Qiang Ma, Fan Yang, Peng-Li He
The Mg isotopic compositions display a significant disparity between the lower continental crust and the mantle. However, due to the limited availability of representative samples from the lower crust, our understanding remains incomplete regarding whether Mg isotope fractionation occurred during its formation and its potential influence on the observed isotopic differences. This study addresses this
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A model for the solubilities of corundum in aqueous NaCl and/or SiO2 solutions and its implication for the mobility of aluminum at depth Chem. Geol. (IF 3.6) Pub Date : 2024-07-02 Xunli Shi, Lin Zhang, Jiawen Hu, Shide Mao
Unlike the solubility models relying on the density or dielectric constant of water, a classical and general framework is established for the solubility models of insoluble minerals using the dissolution equilibrium condition and the chemical potentials of the mineral and aqueous species. By analyzing the chemical potential of water and the dissolution equilibrium condition, we found a nearly linear
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Identification of carbonated eclogitic source for Cenozoic intraplate alkaline basalts from western Central Asia and its geodynamic implication Chem. Geol. (IF 3.6) Pub Date : 2024-06-29 Tianyi Niu, Yuping Su, Jianping Zheng, Liang Zhou, Jian Wang, Xi Chen, Xiao Bian, Xiahui Zhang
Carbonated eclogite has been identified as a significant component in the formation of intraplate alkaline basalts, typically attributed to stagnated subducted oceanic slabs, such as the Pacific plate beneath eastern China. However, it is unclear whether this component exists in other tectonic settings. Here, we present new zircon UPb geochronology, mineral chemistry, and geochemical analyses of Cenozoic
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Fluid-mediated Cu and Zn isotope fractionation in subduction zones and implications for arc volcanism: Constraints from high pressure veins within eclogites in the Dabie Orogen Chem. Geol. (IF 3.6) Pub Date : 2024-06-29 Jian Huang, Shubin Fang, Shun Guo
High-pressure (HP) veins in eclogites are the products of fluid-rock interaction and provide insight into the composition and evolution of fluids in subduction zones. We here present the Cu and Zn isotope data for different types of HP veins and their host eclogites from Ganghe and Hualiangting in the Dabie Orogen to reveal the behavior of Cu and Zn isotopes during fluid-rock interaction and fluid
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Characterizing the combined impact of nucleation-driven precipitation and secondary passivation on carbon mineralization Chem. Geol. (IF 3.6) Pub Date : 2024-06-28 Lawrence Opoku Boampong, Jeffrey D. Hyman, William J. Carey, Hari S. Viswanathan, Alexis Navarre-Sitchler
The evolution of mineral reactive surface area is one of the primary phenomena controlling the progression and extent of mineral carbonation. The CO mineralization begins with nucleation of crystals that provide initial surface area for subsequent growth of the mineral. However, many reactive transport models (RTMs) for CO mineralization do not include the nucleation process. The few RTMs that do include
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Early fluid exsolution suppressed sulfide saturation in Triassic arc volcanic rocks from the Gangdese belt: Implications for Cu depletion in arc magmas and mineralization potential Chem. Geol. (IF 3.6) Pub Date : 2024-06-27 Xu Liu, Zhong-Jie Bai, Hong Zhong, Jin-Lei Sun, Wei-Guang Zhu, Lan Chen
The formation of porphyry–epithermal CuAu deposits depends critically on Cu and Au fertility of arc magmas. Arc magmas commonly exhibit decreasing Cu and Au contents during magmatic differentiation, which is believed to result from sulfide saturation. However, the Cu and Au contents of the arc magmas would also be impacted by fluid exsolution, particularly when magma differentiation occurs in thin
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A geochemical model for the transformation of gabbro into vesuvianite-bearing rodingite Chem. Geol. (IF 3.6) Pub Date : 2024-06-27 Juraj Butek, Sébastien Fabre, Stéphanie Duchene, Ján Spišiak, Michel Grégoire
Rodingite is a Ca-rich and Si-poor metasomatic rock commonly occurring in association with serpentinites. This rock is characterized by specific mineral assemblages consisting of hydrated garnet, diopside, vesuvianite, epidote-zoisite, chlorite, or prehnite. However, natural rodingites are significantly heterogeneous in mineral composition and vesuvianite occurs only in some extensively rodingitized
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Nanoscale characterization of Ediacaran microfossils from lower Doushantuo formation chert nodules Chem. Geol. (IF 3.6) Pub Date : 2024-06-26 Shiqi Cheng, Lianjun Feng, Chaoqun Zhang, Linhao Cui, Wei Liu, Hao Qiu, Shi He, Xuelei Chu, Xingliang Zhang, Jinhua Li
Microfossils identification, especially in very old rocks, is extremely challenging because morphological and chemical signatures of microfossils are subtle and inevitably altered with aging. Chert nodules from the Doushantuo Formation in the Yangtze Gorges area of South China have captured significant interest due to their remarkable preservation of Ediacaran microfossils. To understand the taphonomic
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Dehydration of goethite during vacuum step-heating and implications for he retentivity characterization Chem. Geol. (IF 3.6) Pub Date : 2024-06-25 K.A. Farley, H.B. Monteiro, P.M. Vasconcelos, K. Waltenberg
Uncertainty exists over what environmental conditions and mineralogical/chemical properties are required to ensure retention of helium such that (UTh)/He dates record the time of goethite crystallization. We undertook vacuum step heating experiments to determine He diffusion parameters for extrapolation to Earth surface conditions on 10 goethite specimens in which we had created a uniform distribution
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Weathering-induced Sb isotope fractionation during leaching of stibnite and formation of secondary Sb minerals Chem. Geol. (IF 3.6) Pub Date : 2024-06-25 Andreas B. Kaufmann, Marina Lazarov, Ingo Horn, Martin Števko, Tamara Ðorđević, Stefan Kiefer, Stefan Weyer, Juraj Majzlan
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Rare earth element enrichment process of bioapatite in deep-sea REY-rich sediments Chem. Geol. (IF 3.6) Pub Date : 2024-06-25 Hao Wang, Zhenggang Li, Yanhui Dong, Bin Fu, Xiaohu Li, Jie Li, Fengyou Chu, Weiyan Zhang, Zhiming Zhu, Jihao Zhu, Ling Chen
Rare earth element and yttrium (REY) compositions of bioapatite (e.g., fish tooth and bone) can serve as potential paleoceanographic indicators. However, the REY enrichment of bioapatite and REY transfer from FeMn micronodule to bioapatite remain unclear owing to a lack of comparative study on these processes under variable redox conditions (oxic vs. suboxic), which hampers the utility of these indicators
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Heavy sulfur isotopes recorded in contrasted redox conditions in Holocene sediments from the Yangtze River Delta Chem. Geol. (IF 3.6) Pub Date : 2024-06-23 Yinglu Chen, Weiguo Zhang, Xiaomei Nian, Yongjie Wang, Ian Snowball, Bjarne Almqvist, Yu Hu, Xinyu Jiang, Jiabing Tang, Zice Jia
Sulfur isotopic signatures of pyrite (δS) sensitively react to local environmental change. Here we elucidate mechanism of δS variation in the Holocene sedimentary strata of the Yangtze River Delta, through the analyses of multiple geochemical and physical indicators including total organic carbon, total nitrogen, stable isotopes of organic carbon, different iron solid phases, Sr/Ba ratios, and changes
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Enhanced mobility of iron and manganese on Mars: Evidence from kinetic experiments and models Chem. Geol. (IF 3.6) Pub Date : 2024-06-23 Matteo Loche, Sébastien Fabre, Agnès Cousin, Arnaud Proietti, William Rapin, Benjamin M. Tutolo, Pierre-Yves Meslin, Anissa Benmammar, Foteine Dimitracopoulos, Roger C. Wiens, Olivier Gasnault
Several missions have reported complex alteration mineralogies on early Mars, which preserve environmental records of multiple water-rock-atmosphere interactions. The MSL and M2020 missions in Gale and Jezero have identified Fe and Mn-bearing secondary phases. These elements are used as tracers for the redox conditions on both Earth and Mars. However, to fully understand the short-lived and local-scale
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Origin of discordant U[sbnd]Pb dates in non-metamict zircons in intrusives deformed at granulite facies: Grain scale processes, and relevance to Cambrian orogeny, Eastern Ghats Belt, India Chem. Geol. (IF 3.6) Pub Date : 2024-06-22 Anwesa Banerjee, Sandra Piazolo, Nathan Cognè, Abhijit Bhattacharya, N. Prabhakar
Interpreting the origin of UPb discordance in zircons in intrusives that experience high metamorphic-deformation events is challenging. We investigate in depth the origin of UPb dates obtained from garnet-bearing border zone granitoids and a sheared ferrodiorite dyke bordering the Balangir anorthosite pluton, eastern India. The crustal domain is known for discordant ages resulting in disputes regarding
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Clay minerals control silicon isotope variations of fine-grained river sediments: Implication for the trade-off between physical erosion and chemical weathering Chem. Geol. (IF 3.6) Pub Date : 2024-06-22 Chen Ling, Zhifei Liu, Xun Yu, Yulong Zhao, Fernando P. Siringan, Khanh Phon Le, Edlic Sathiamurthy, Chen-Feng You, Kaiyun Chen
Stable silicon (Si) isotopes in fluvial sediments can provide insights into understanding silicate weathering processes on the Earth's surface. However, a lack of comprehensive studies has hindered full understanding of the factors influencing Si isotope fractionation during continental weathering. In this study, through the analysis of Si isotopes in fine-grained sediments from 13 rivers surrounding
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Increase of chemical weathering in the Lena River Catchment under a warmer climate Chem. Geol. (IF 3.6) Pub Date : 2024-06-22 Xiaole Sun, Carl-Magnus Mörth, Don Porcelli, Christoph Humborg, Liselott Kutscher, Catherine Hirst, Melissa J. Murphy, Trofim Maximov, Roman E. Petrov, Per S. Andersson
Permafrost degradation has led to increased riverine ion concentrations and export to the sea. This study uses major ion data collected in summer in 2012 and 2013 and during spring flood in 2015 to investigate the spatio-temporal variability in chemical weathering patterns and the associated CO consumptions in one of the major Arctic Rivers – the Lena River and its tributaries. The catchment shows
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Molybdenum isotopic evidence for the initiation of a big mantle wedge beneath eastern Asia Chem. Geol. (IF 3.6) Pub Date : 2024-06-22 Wei Fang, Li-Qun Dai, Zi-Fu Zhao, Qi Chen, Jun Yan, Dayu Zhang, Ding-Sheng Jiang
The subduction of the Paleo-Pacific plate and the formation of a big mantle wedge have influenced the tectonic-magmatic evolution of eastern Asia. However, the timing and mechanism of big mantle wedge formation remain obscure. Here we report molybdenum (Mo) isotope compositions of Mesozoic-Cenozoic mafic rocks in eastern China, which provide constraints on the geodynamics of Paleo-Pacific subduction
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Highly efficient purification of long-chain alkenones using silver dimercaptotriazine flash chromatography Chem. Geol. (IF 3.6) Pub Date : 2024-06-22 Lu Wang, Yuan Yao, Yongsong Huang, Yinan Zhao, Hai Cheng
Long-chain alkenones (LCAs) are important tools for paleotemperature reconstructions in lacustrine and marine environments. However, some neutral lipid compounds that co-elute with LCAs often occur in natural sediment samples, which seriously interferes with the identification and quantification of the LCAs. In this study, we report a new flash column chromatography based on silver(I)-dimercaptotriazine
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The spatial–temporal evolution of Neotethyan subduction in central to Southeast Iran: Constraints from geochemistry, zircon U–Pb–Hf, and Sr–Nd–Pb isotopes Chem. Geol. (IF 3.6) Pub Date : 2024-06-21 Shahrouz Babazadeh, Davood Raeisi, M. Santosh, Tanya Furman, Sung Hi Choi, Massimo D'Antonio
Igneous rocks in central Iran preserve proof of several episodes of Late Mesozoic–Cenozoic Neotethyan subduction, and record temporal and spatial variations from subduction to collisional geodynamic regimes that remain a subject of debate. We revisit magmatic rocks from the central Urumieh–Dokhtar magmatic arc (UDMA; 32° 30′ N to 36° 00′ N) and report new major and trace element analyses, whole-rock
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Contributing to understand how Cordilleran batholiths build from detailed geochronology of the Carboniferous Tabaquito batholith, Frontal Cordillera (Argentina) Chem. Geol. (IF 3.6) Pub Date : 2024-06-21 Gilmara Santos da Cruz, Juan A. Moreno, Juan A. Dahlquist, Matías M. Morales Cámera, Miguel A.S. Basei, Priscila S. Zandomeni
Cordilleran Granitic batholiths or Andean/Cordilleran batholiths serve as plutonic expressions of continental arcs, offering valuable insights into the processes that operate in large silicic magmatic systems at subduction environments. This work presents a comprehensive geochronological study of the Carboniferous Tabaquito batholith in the Frontal Cordillera of western Argentina, which is the best
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Ocean acidification in the tropical Indian Ocean over the past 37 years: Insights from [formula omitted]11B and B/Ca records in a Maldives coral Chem. Geol. (IF 3.6) Pub Date : 2024-06-21 Yi-Wei Liu, Ke Lin, Kyle Morgan, Xianfeng Wang
Boron isotopes (B) in coral skeletons of have been widely applied to reconstruct past seawater pH (pH) on decadal to centennial timescales. However, due to biological regulation within corals, an additional transfer function is required to estimate ambient seawater chemistry during the skeleton growth under the calcification site fluid pH. Temperature may also interfere with coral calcification fluid
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Organo-mineral interaction between plastic film and sedimentary rock induced by UV irradiation Chem. Geol. (IF 3.6) Pub Date : 2024-06-20 Liuwei Wang, Jing Guo, Michael S. Bank, Lukas Van Zwieten, Nanthi S. Bolan, Wei-Min Wu, Deyi Hou
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Geochemistry of carbonate microbialites through time and space: Insights from the microbialite collection of the Muséum National d'Histoire Naturelle (MNHN), France Chem. Geol. (IF 3.6) Pub Date : 2024-06-19 Laurane Fogret, Pierre Sansjofre, Stefan V. Lalonde
Microbialites are microbial sedimentary structures that constitute some of the oldest traces of life on Earth. By their deposition in a wide range of sedimentary environments and their presence throughout most of geological time, the sedimentological and geochemical signatures they preserve represent important paleoenvironmental archives for understanding Earth's biological and geochemical co-evolution
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An electron backscatter diffraction study of monazite: Linking the time-deformation path Chem. Geol. (IF 3.6) Pub Date : 2024-06-18 Catherine M. Mottram, John M. Cottle
Monazite, (Ce,REE)PO, is a common accessory mineral used to quantify the timing and duration of tectono-metamorphic processes in (poly)metamorphosed orogenic terranes. As monazite frequently yields a spread of dates, there can be ambiguity linking age domains to specific metamorphic reactions and/or deformation events. This study aims to: (1) discern the effect of deformation on the monazite crystal
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Experimental constraints on the pre-eruptive conditions of the Caxias do Sul dacite: Implications for high temperature silicic volcanism of the Paraná Magmatic Province, Brazil Chem. Geol. (IF 3.6) Pub Date : 2024-06-18 Emily C. Bamber, Daniele Giordano, Matteo Masotta, Fabio Arzilli, Fabio Colle, Diego González-García, Valdecir de Assis Janasi, Fábio Ramos Dias de Andrade, Silvio R.F. Vlach, Michael R. Carroll, Donald B. Dingwell
The Paraná-Etendeka Magmatic Province is the second largest continental large igneous province (LIP) known. It is characterised by the occurrence of an unusually high proportion (∼3%) of silica-rich magmatic products (dacitic to rhyolitic in composition). Here we provide the first experimental constraints on the pre-eruptive crystallisation conditions of the Caxias do Sul dacite (CSd), the oldest silicic
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Effects of gamma(γ)-irradiation on the physicochemical properties and bioavailability of iron oxyhydroxides coprecipitated with varying concentrations of Na-alginate Chem. Geol. (IF 3.6) Pub Date : 2024-06-17 Tarek Najem, Prachi Joshi, Andreas Kappler, Danielle Fortin
This study investigated the impacts of γ-radiation at a final dose of 25 kGy on the physicochemical properties of a range of wet iron oxyhydroxides (2-line ferrihydrite, lepidocrocite, and goethite) synthesized in the presence of varying concentrations of the polysaccharide Na-alginate (starting solutions containing C/Fe ratios of 0, 0.5, 1.0, and 1.5). The degree of impact to the minerals was examined
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A distinct manganese deposit on a Middle Permian carbonate platform in South China Chem. Geol. (IF 3.6) Pub Date : 2024-06-15 Wenchao Yu, Zhichen Liu, Bolin Zhang, Daoliang Chu, Wei Wei, Lin Xiao, Deng Chen, Yuansheng Du, Leslie J. Robbins, Kurt Konhauser
During the Middle Permian, Earth experienced a period of profound environmental changes, including the final stages of the Late Paleozoic Ice Age (LPIA), global seawater regression, the Guadalupian mass extinction event, and the eruption of the Emeishan Large Igneous Province (ELIP) in South China. These events collectively induced significant shifts in both the environment and biosphere, yielding
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Behaviour of fluid-mobile elements across a high-pressure serpentinization front (Monte Maggiore unit, Alpine Corsica) Chem. Geol. (IF 3.6) Pub Date : 2024-06-14 Francesco Ressico, Enrico Cannaò, Orlando Sébastien Olivieri, Zeudia Pastore, Veronica Peverelli, Nadia Malaspina, Alberto Vitale Brovarone
Subducted sections of dry oceanic mantle can undergo serpentinization through interaction with metamorphic fluids, recording a sequence of serpentinization events from the subseafloor to serpentine-out reactions. The geochemical patterns of these different stages of fluid-rock interaction trace the context and mechanisms of serpentinization processes. In this study, we used petrographic observations
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Nickel's behaviour in marine sediments under aerobic to anaerobic diagenetic conditions Chem. Geol. (IF 3.6) Pub Date : 2024-06-14 Sylvie Bruggmann, James McManus, Corey Archer, Derek Vance, Silke Severmann
In the marine environment, nickel distributions are linked to the biogeochemical cycling of both organic matter and manganese. Thus, Ni and its isotopes have the potential to be used to reconstruct changes of bioproductivity and oxygenation in paleoenvironments. However, their utility relies on an understanding of the behaviour of Ni in modern marine environments. Here we investigate the distribution
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Role of manganese oxides and oxyhydroxides in phosphate sequestration in natural aquatic environments Chem. Geol. (IF 3.6) Pub Date : 2024-06-13 Pierre Anschutz, Florian Benony, Céline Charbonnier
Excessive inputs of phosphorus (P) to aquatic environments can lead to eutrophication. Adsorption of phosphate on Fe oxides is one of the main process that can limit P availability. Oxidized forms of Mn have also been suggested to play a role in P trapping. However, although a considerable number of studies have shown the relationships between the geochemistry of Fe and that of phosphates, few studies
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Sources of limestone dissolution from surface water-groundwater interaction in the carbonate critical zone Chem. Geol. (IF 3.6) Pub Date : 2024-06-13 Andrew Oberhelman, Jonathan B. Martin, Madison K. Flint
Dissolution of carbonate minerals in karst aquifers has long been recognized to result from recharge of surface water undersaturated with respect to calcite from carbonic acid produced by hydration of dissolved atmospheric and respired CO. However, dissolution also results from additional acids produced by reactions of redox sensitive solutes in the subsurface, which may represent a source of CO to
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Unravelling instrumental mass fractionation of MC-ICP-MS using neodymium isotopes Chem. Geol. (IF 3.6) Pub Date : 2024-06-13 Yang Yu, Ed Hathorne, Chris Siebert, Marcus Gutjahr, Jan Fietzke, Martin Frank
Since the initial discovery of the non-exponential mass fractionation (non-EMF) of Nd isotopes analysis in 2002, similar deviations from an EMF pattern have been reported for measurements of a number of isotope systems (e.g., Si, Ge, Sr, Sn, Ba, Yb, W, Os, Hg and Pb) with MC-ICP-MS. However, the previous controversial reports on the magnitude of the deviations from EMF suggest that instrumental mass
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Origins of authigenic gypsums and carbonate minerals in sediments at a cold seep site in the Sea of Marmara Chem. Geol. (IF 3.6) Pub Date : 2024-06-13 Yukai Tang, Hailin Yang, Hailong Lu, Namik Çağatay, Xindi Lu, Yujia Liu, Livio Ruffine, Yongbo Peng, Lin Dong, Jiujiang Zhao, Yixuan Zhang
In the Western High of the Sea of Marmara, where pervasive gas hydrate and hydrocarbon gas seepage occurs, late Pleistocene-Holocene sediments are composed of a lower lacustrine and an upper marine unit. The sedimentary evolution, gypsum formation and carbonate anomaly, under the complex sedimentary environment at cold seep sites on the Western High, have not been systematically well explained. The
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Late Archean K-rich intermediate magmatism driven by deep supracrustal recycling Chem. Geol. (IF 3.6) Pub Date : 2024-06-12 Wei Wang, Yongjun Lu, Lei Gao, Guozheng Sun, Xingzhi Zhou, Jiachen Yao, Weibo Yang, Xueyin Liang
Archean K-rich intermediate rocks hold important information of crust-mantle geodynamic evolution of the early Earth. However, the nature of their magma sources and thermodynamic origin remain enigmatic. Two distinct groups of late Neoarchean (∼2551–2498 Ma) K-rich intermediate rocks were identified in the North China Craton. The high-Mg group is compositionally similar to low-Ti sanukitoids, and includes
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Reconstructing the depositional environment and diagenetic modification of global phosphate deposits through integration of uranium and strontium isotopes Chem. Geol. (IF 3.6) Pub Date : 2024-06-12 Robert C. Hill, Zhen Wang, Gordon D.Z. Williams, Victor Polyak, Anjali Singh, Michael A. Kipp, Yemane Asmerom, Avner Vengosh
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Study of olivine-hosted melt and spinel inclusions from the Song Da ultramafic volcanic suite, northern Vietnam: Compositions, crystallization temperatures, and origin of the low-Ti komatiite-like and high-Ti primary melts Chem. Geol. (IF 3.6) Pub Date : 2024-06-11 Charbel Kazzy, Alexander V. Sobolev, Valentina G. Batanova, Evgeny V. Asafov, Eero Hanski, Igor S. Puchtel, Andrey E. Izokh, Leonid V. Danyushevsky, Vũ Hoàng Ly, Can Pham-Ngoc, Tran Tuan Anh
The Permian (∼260 Ma) Song Da volcanic suite in Vietnam is one of very few known occurrences of Phanerozoic ultramafic volcanic rocks that are similar in composition to komatiites. Despite continuous efforts to determine the primary melt composition of Song Da ultramafic lavas, the concentrations of the volatile and fluid-mobile elements are still poorly constrained due to widespread alteration and
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Why are oceanic arc basalts Ca-rich and Ni-poor? Insights from olivine-hosted melt inclusions from Kibblewhite Volcano in the Kermadec arc Chem. Geol. (IF 3.6) Pub Date : 2024-06-11 Yasuhiro Hirai, Yoshihiko Tamura, Takeshi Hanyu, Qing Chang, Christian Timm, Kaj Hoernle
Ankaramites, which are clinopyroxene-rich basalts with primitive whole-rock compositions (Mg# >65), are common in oceanic arcs and are characterized by high whole-rock CaO/AlO (>1.0) ratios and olivine crystals with anomalously low nickel contents (<0.2 wt% NiO). These geochemical characteristics cannot be explained by the melting of ordinary mantle peridotite. However, their origin is critical for
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Continuous deposition of pre-aged organic carbon in the southern Mariana Trench since the last deglaciation Chem. Geol. (IF 3.6) Pub Date : 2024-06-11 Da-Wei Li, Mengna Chen, Shuai Liu, Hailong Zhang, Zicheng Wang, Xiaoyan Ning, Jiwei Tian, Meixun Zhao
One of the key challenges in understanding the role of hadal trenches in the marine organic carbon (OC) cycle is the need to distinguish OC sources, assess accumulation rates, and identify controlling processes. To address this, sediment core samples from the southern Mariana Trench were analyzed for their contents and carbon isotopes (C and C) of both total OC (TOC) and saturated long-chain fatty
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Application of pyrite trace-metal and S and Ni isotope signatures to distinguish sulfate- versus iron-driven anaerobic oxidation of methane Chem. Geol. (IF 3.6) Pub Date : 2024-06-10 Can Chen, Jiasheng Wang, Thomas J. Algeo, Jian-Ming Zhu, Simon W. Poulton, Zhou Wang, Cong Cheng, Qiang Song
The formation of authigenic pyrite in marine sediments involves multiple reactions between ferrous iron (Fe) and hydrogen sulfide (HS). Ferrous iron is commonly provided through the reductive dissolution of Fe-(oxyhydr)oxides by organic matter (i.e., dissimilatory Fe reduction), dissolved sulfide (i.e., abiotic Fe reduction) or methane (i.e., Fe-AOM), whereas sulfide is supplied by organoclastic sulfate
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Genetic relationship between petroleum evolution and mercury mineralization: Insights from calcite U[sbnd]Pb dating, geochemical characterization, and solid bitumen TEM analysis Chem. Geol. (IF 3.6) Pub Date : 2024-06-09 Xiang Ge, Shuaiping Li, Yinpeng Zhu, Wenpan Cen, Bing Li, Yuexing Feng, Guangyou Zhu, Chuanbo Shen
A spatial association between hydrocarbon reservoirs and metalliferous deposits is found worldwide. However, the genetic relationship between them is unclear. The associated fluids record information related to petroleum evolution and mineralization. Integrating UPb dating and geochemical analysis on calcite associated with either bitumen or cinnabar and transmission electron microscopy analysis of
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Local and global controls on carbon and sulfur isotope records in the Middle Ordovician Epeiric sea successions of the Taebaeksan Basin, Korea Chem. Geol. (IF 3.6) Pub Date : 2024-06-09 Hyosang Kwon, Sunhwa Bang, Young Ji Joo, Min Sub Sim
Although the sedimentary carbonate carbon isotope record is generally considered a reliable archive of long-term changes in the global carbon cycle, the influences of local variability in carbon cycling and diagenesis frequently overwhelm its global controls, particularly in shallow platform environments. During the Middle Ordovician period, the middle Darriwilian isotopic carbon excursion (MDICE)
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Oceanic euxinia and seafloor oxygenation linked to continental weathering and influxes during the Late Devonian Frasnian–Famennian bio-crisis and Annulata bio-event Chem. Geol. (IF 3.6) Pub Date : 2024-06-08 Jian Chen, YueHan Lu, YongGe Sun, Nicholas Hogancamp, Man Lu
Oceanic anoxia is regarded as the immediate cause of the Late Devonian Frasnian–Famennian (F–F) bio-crisis and Annulata bio-event. The oceanic anoxia has been linked to continental weathering and input. However, some previous findings indicate oxic marine environments during the F–F bio-crisis. Moreover, the relative impact of terrestrial input on the Late Devonian oceanic redox conditions, when comparing
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The influence of hydrogeology and carbon sources on speleothem δ13C based on long-term monitoring in Furong Cave, southwest China Chem. Geol. (IF 3.6) Pub Date : 2024-06-07 Jun-Yun Li, Ting-Yong Li, Hong-Chun Li, Christoph Spötl, Chao-Jun Chen, Jian Zhang, Yao Wu, Hua-Yan Li, Yue Jin, Min Zhao, Hong-Kai Li, Yan-Min Dong
The stable carbon isotopic composition of speleothems is an important but incompletely understood parameter in paleoclimatological and paleoenvironmental reconstruction, recording changes in vegetation and hydrology. This study systematically assesses the influences of karst hydrology, cave environment, and carbon sources on the δC values of farmed calcite in Furong Cave, located in Chongqing, southwest
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Zinc isotopic evidence for enhanced continental weathering and organic carbon burial in the Early Silurian Chem. Geol. (IF 3.6) Pub Date : 2024-06-07 Xiangrong Yang, Detian Yan, Mu Liu, Xianyi Liu, Yin Gong, Liwei Zhang, Bao Zhang, Daizhao Chen
The Late Ordovician and Early Silurian periods experienced glaciation and mass extinctions. However, debates exist regarding the factors that initiated the glaciation and the subsequent delay in biotic recovery. To uncover the relationships between paleoclimate, marine redox states, and biotic recovery in the Early Silurian, temporal variations in Zinc (Zn) isotopic compositions along with other multi-geochemical
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Distribution of trace and rare earth elements in the estuary of Ría de Huelva (SW Spain): Field data and geochemical modeling Chem. Geol. (IF 3.6) Pub Date : 2024-06-06 Joan Gutiérrez-León, Ricardo Millán-Becerro, Sergio Carrero, Rafael Pérez-López, Elina Ceballos, Rémi Freydier, Josep M. Soler, Jordi Cama
The geochemistry of the Ría de Huelva estuary (Spain) has been widely studied owing to its unique conditions due to mixing of acid mine drainage (AMD), river water and seawater, which have been aggravated by the existence of an adjacent phosphate fertilizer plant and its associated phosphogypsum stack.
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Redox indication potential of isoprenoid tetraether lipids in marine environments: Insights from the East China Sea Chem. Geol. (IF 3.6) Pub Date : 2024-06-06 Liqin Duan, Jinming Song, Huamao Yuan, Xuegang Li, Quancai Peng
The response of marine ammonia-oxidizing archaea (AOA) to environmental stress is reflected in changes in their membrane lipid composition, particularly the unique isoprenoid glycerol dialkyl glycerol tetraethers (iGDGTs). However, the influence of dissolved oxygen (DO) on the composition of iGDGTs in the ocean remains unclear. This study aims to investigate the link between DO levels and the fractional
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The effect of diffusion on lithium isotope ratios in Icelandic basalts Chem. Geol. (IF 3.6) Pub Date : 2024-06-06 Edward W. Marshall, Sæmundur A. Halldórsson, Liyan Tian, Matthew G. Jackson, Frances Jenner, Andri Stefánsson
In recent years, diffusion has gained increasing recognition as an important process for explaining the lithium (Li) isotope ratios (δLi) of magmatic systems. However, the role of diffusion in explaining the variability of mantle-derived basalts has not yet been investigated in detail. We have measured δLi values in a comprehensive suite of fresh, subglacial Icelandic basalt glasses and observe a wide
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Biotite dissolution kinetics at pH 4 and 6.5 under anaerobic conditions and the release of dissolved Fe(II) Chem. Geol. (IF 3.6) Pub Date : 2024-06-05 Stellan Holgersson, Henrik Drake, Andreas Karlsson, Lindsay Krall
Dissolution of biotite, the main Fe-bearing mineral in granitic bedrock, is of particular importance for the remediation of reducing conditions after the ingress of oxygen, such as after mining activities or the construction of deep repositories for toxic waste. This study investigated the leaching of biotite of size fraction 0.053–0.075 mm under anaerobic conditions at room temperature and pH 4 and
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Deciphering ore genesis with oxygen and sulfur isotope signatures: A case study from the Singhbhum Shear Zone, Eastern India Chem. Geol. (IF 3.6) Pub Date : 2024-06-01 Susobhan Neogi, Trisrota Chaudhuri, Manish Banerjee, Debojit Talukdar, Sandip Nandy
The importance of light-stable isotopes and their mass-dependent fractionations in understanding past geological processes is enormous. The present research delivers precise, high-resolution, in-situ oxygen (O) and triple sulfur (S) isotope ratios from quartz and sulfide minerals found in the CuAu Kendadih deposit located along the Mesoproterozoic (∼1.6 Ga) Singhbhum Shear Zone (SSZ) in eastern India
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Direct prediction of isotopic properties from molecular dynamics trajectories: Application to sulfide, sulfate and sulfur radical ions in hydrothermal fluids Chem. Geol. (IF 3.6) Pub Date : 2024-05-31 Marc Blanchard, Elsa Desmaele, Gleb S. Pokrovski, Carlos Pinilla, Merlin Méheut, Rodolphe Vuilleumier
In hydrothermal fluids, disulfur (S) and trisulfur (S) radical anions have been observed to coexist with the major hydrogen sulfide and sulfate species. These radical ions have potentially important effects on the solubility, transport and fractionation of metals and sulfur, with consequences for ore deposit formation and, more generally, for geochemical cycles of metals and volatiles. It is therefore
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Trace metal and organic biosignatures in digitate stromatolites from terrestrial siliceous hot spring deposits: Implications for the exploration of martian life Chem. Geol. (IF 3.6) Pub Date : 2024-05-29 Ema E. Nersezova, Michael C. Rowe, Kathleen A. Campbell, Andrew Langendam, Cherie Tollemache, Barbara Lyon, Amanda Galar, Diego M. Guido, Bronwyn L. Teece, Trinity L. Hamilton
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Authigenic quartz reveals the triple oxygen isotope composition and diagenetic temperature of saline brines Chem. Geol. (IF 3.6) Pub Date : 2024-05-28 Fabian Zahnow, Michael Tatzel, Jakub Surma, Andreas Pack
Triple oxygen isotope compositions of authigenic minerals are an emerging tool for the reconstruction of fluid temperatures and the fluid isotopic composition. In this study, we analyzed euhedral authigenic quartz crystals from a halite deposit of the Upper Permian Zechstein evaporitic basin for their triple oxygen isotope composition using laser fluorination isotope ratio mass spectrometry. In the
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A numerical model for the quantification of fluid inclusion property variations caused by heterogeneous entrapment and post-entrapment modifications in the H2O-NaCl system Chem. Geol. (IF 3.6) Pub Date : 2024-05-28 Wei Mao, Thomas Ulrich, Hong Zhong
The primary geological conditions for hydrothermal systems can be reconstructed using fluid inclusions, which generally requires that fluid inclusions trapped a single homogeneous phase and experienced no mass and volume changes after entrapment (Roedder's Rules). However, heterogeneous entrapment and post-entrapment modifications have been frequently identified in fluid inclusion studies, making the
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Experimental incorporation of U into xenotime at mid to lower crustal pressures and temperatures utilizing alkali-bearing fluids under reducing and oxidizing conditions Chem. Geol. (IF 3.6) Pub Date : 2024-05-27 Daniel E. Harlov
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Evaluating reference materials and common-Pb corrections for high-resolution apatite U[sbnd]Pb geochronology Chem. Geol. (IF 3.6) Pub Date : 2024-05-27 Francisco E. Apen, Sean P. Gaynor, Blair Schoene, John M. Cottle
We report isotope dilution thermal ionization mass spectrometry (ID-TIMS) and laser ablation split stream inductively coupled plasma mass spectrometry (LASS) UPb data for a suite of widely available reference apatites: Fish Canyon Tuff, Mount Dromedary, TEMORA 2, and Duluth Complex anorthosite. We apply different common-Pb correction strategies to the UPb data sets: (1) anchoring to a Stacey and Kramers
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Identification of variable contributions to arc rocks by Li[sbnd]Mo and Sr–Nd–Hf–O isotope compositions: A study of the Mafan mafic rocks in the Hong'an orogen, Central China Chem. Geol. (IF 3.6) Pub Date : 2024-05-26 Huan Chang, Yujie Zhao, Pan Hu, Guangyan Zhou, Wenxiang Zhang, Lian Zhou, Jie Lin, Zhaochu Hu, Yuanbao Wu
The geochemistry of arc rocks provides a window to probe compositional variability in mantle wedge and slab-derived inputs. However, quantitative estimation of their contribution is a great challenge. Here we report an integrated study for determination of variable contributions to early Paleozoic arc plutons (the Mafan diorites and gabbros), from the northern Hong'an orogen, central China. Zircon