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Unraveling microbial processes involved in carbon and nitrogen cycling and greenhouse gas emissions in rewetted peatlands by molecular biology Biogeochemistry (IF 4.0) Pub Date : 2024-03-16 Emilie Gios, Erik Verbruggen, Joachim Audet, Rachel Burns, Klaus Butterbach-Bahl, Mikk Espenberg, Christian Fritz, Stephan Glatzel, Gerald Jurasinski, Tuula Larmola, Ülo Mander, Claudia Nielsen, Andres F. Rodriguez, Clemens Scheer, Dominik Zak, Hanna M. Silvennoinen
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Labile organic matter promotes nitrogen retention in natural and constructed gulf coast marshes Biogeochemistry (IF 4.0) Pub Date : 2024-03-13 S. F. Starr, B. Mortazavi, C. Tatariw, K. A. Kuehn, J. A. Cherry, T. Ledford, E. Smyth, A. Griffin Wood, S. E. Sebren
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Disentangling effects of multiple agricultural stressors on benthic and hyporheic nitrate uptake Biogeochemistry (IF 4.0) Pub Date : 2024-03-13 Julia Pasqualini, Daniel Graeber, Alexander Bartusch, Steffen Kümmel, Zulma Lorena Duran Hernandez, Niculina Musat, Nergui Sunjidmaa, Markus Weitere, Mario Brauns
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Molar-Tooth Carbonate: An excellent proxy for reconstructing lithium isotopic composition of Precambrian seawater Chem. Geol. (IF 3.9) Pub Date : 2024-03-12 Tingyu Yang, Yilin Xiao, Yang-Yang Wang, Hongwei Kuang, Jack Geary Murphy, Erhao Shan, Ling-Ling Jiang, Xiangying Ye, He Sun, Haiou Gu
Shallow water carbonates are extensively utilized as archives for reconstructing past seawater chemistry and understanding global geochemical cycles. However, their reliability is often compromised by diagenetic alteration, obscuring primary environmental signals. Molar-tooth carbonate (MTC) exhibits exceptional resistance to diagenesis compared to other carbonate minerals, making it a promising candidate
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Testing the reproducibility of in situ Lu[sbnd]Hf dating using Lu-rich garnet from the Tørdal pegmatites, southern Norway Chem. Geol. (IF 3.9) Pub Date : 2024-03-12 Stijn Glorie, Alexander Simpson, Sarah E. Gilbert, Martin Hand, Axel B. Müller
In situ LuHf geochronology offers the potential for direct dating of garnet within petrographic context. However, the method requires matrix-matched standards to calibrate measured Lu/Hf ratios. In order to assess the accuracy of this calibration, as well as the reproducibility of the resulting LuHf dates, two Lu-rich (up to 1 wt% Lu) garnet samples from the Tørdal pegmatite field in southern Norway
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Post-cratering melting of target rocks at the impact melt contact: Observations from the Vredefort impact structure, South Africa Chem. Geol. (IF 3.9) Pub Date : 2024-03-12 M.S. Huber, E. Kovaleva, D.A. Zamyatin, A.A. Davletshina, V. Fernandez, T. Salge
Impact melt is generated following hypervelocity impact events. Emplacement of impact melt dikes, such as the Vredefort Granophyre Dikes, allow for this high temperature melt to come into contact with deeply-buried target rocks after the cratering process is completed. Our study analyzes the effects of this interaction by examining the direct contact between the Vredefort Granophyre and the granitic
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Disentangling the effects of temperature and reactive minerals on soil carbon stocks across a thermal gradient in a temperate native forest ecosystem Biogeochemistry (IF 4.0) Pub Date : 2024-03-10 Idri Hastuty Siregar, Marta Camps-Arbestain, Gabor Kereszturi, Alan Palmer, Miko U. F. Kirschbaum, Tao Wang
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Rivers and tidal flats as sources of dissolved organic matter and trace metals in the German Bight (North Sea) Biogeochemistry (IF 4.0) Pub Date : 2024-03-09 Linn G. Speidel, Roger Carvalho da Silva, Melanie Beck, Olaf Dellwig, Jochen Wollschläger, Thorsten Dittmar, Michael Seidel
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Permafrost degradation and its consequences for carbon storage in soils of Interior Alaska Biogeochemistry (IF 4.0) Pub Date : 2024-03-09 Patrick Liebmann, Jiří Bárta, Cordula Vogel, Tim Urich, Alexander Kholodov, Milan Varsadiya, Ole Mewes, Stefan Dultz, Muhammad Waqas, Haitao Wang, Olga Shibistova, Georg Guggenberger
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Lithium isotope fractionation during submarine hydrothermal alteration processes Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-11 Di Cai, Hebin Shao, Long-Fei Gou, Zhangdong Jin, Shouye Yang
River water and submarine hydrothermal fluids are the two primary sources of lithium (Li) input to the ocean. However, compared to well-documented weathering processes, the behavior of Li isotopes during hydrothermal alteration processes remains obscure. In this research, we investigated the Li isotopic compositions (δLi) of hydrothermally altered sediments from two IODP drilling cores (C0013 and C0014)
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Isotopic evolution of the inner solar system revealed by size-dependent oxygen isotopic variations in chondrules Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-11 Yves Marrocchi, Alizé Longeau, Rosa Lozano Goupil, Valentin Dijon, Gabriel Pinto, Julia Neukampf, Johan Villeneuve, Emmanuel Jacquet
The systematic isotopic difference between refractory inclusions and chondrules, particularly for oxygen, has long indicated an isotopic evolution of the solar protoplanetary disk. However, it remains underconstrained whether such evolution continued during chondrule formation. Intrigued by past reports of the size-dependent oxygen isotopic compositions of chondrules in ordinary chondrites (OC), we
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Fluid-mediated exchange reaction induces clumped isotope resetting: Insights from aragonite dolomitization experiments Chem. Geol. (IF 3.9) Pub Date : 2024-03-11 Yangrui Guo, Kai Kong, Xi Liu, Wenfeng Deng, Gangjian Wei
Carbon and oxygen isotopic exchange between external and internal fluids of carbonate minerals can reset the clumped isotope composition (Δ) of paleotemperature archives. Understanding the nature of this exchange during carbonate diagenetic alterations is essential for correctly interpreting the paleoenvironmental significance of Δ-derived temperatures. Through batch hydrothermal experiments on aragonitic
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Are sulfides the primary host of sedimentary Hg? A case study from the lower Jurassic of the Surat Basin (Australia) Chem. Geol. (IF 3.9) Pub Date : 2024-03-11 Yuqing Zhu, Andrew La Croix, David B. Kemp, Jun Shen, Chunju Huang, Xia Hua, Yu Li, Mengchuang Wei
Several mass extinction events and major paleoenvironmental perturbations during the Phanerozoic have been linked to massive volcanic eruptions, especially those associated with large igneous province (LIP) emplacement. Because magmatism during LIPs can be accompanied by the release and widespread dispersal of mercury (Hg), Hg concentration in sedimentary rocks has proven to be a useful proxy for paleovolcanism
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Hourly methane and carbon dioxide fluxes from temperate ponds Biogeochemistry (IF 4.0) Pub Date : 2024-03-08 Jonas Stage Sø, Kenneth Thorø Martinsen, Theis Kragh, Kaj Sand-Jensen
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Influence of goethite nanophase on rare-earth element patterns and enrichment in marine phosphates during early diagenesis Chem. Geol. (IF 3.9) Pub Date : 2024-03-09 Jieqi Xing, Shan Li, Hongyan Wei, Jiaxin Xi, Xiaoju Lin, Yiping Yang, Haiyang Xian, Wei Tan, Jingming Wei, Jianxi Zhu
Although rare-earth elements (REEs) in authigenic phosphates and carbonates derived from marine sediments are potential proxies (e.g., REE patterns) for reconstructing paleoenvironmental conditions, the REE patterns appear to be inconsistent. Some marine authigenic phosphates show a “bell-shaped” pattern with an enrichment of the middle REEs (MREEs; NdHo), while others exhibit a “modern seawater-like”
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Diagenesis of fossil gar fish scales with implications for geochronology and paleoenvironmental applications Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-08 John Fink, Marissa M. Tremblay, Thomas S. Tobin, Lisa D. Stockli, Daniel F. Stockli, Ryan B. Ickert
Fossil scales from gar fish are made of bioapatite and are common in the continental sedimentary record from the Cretaceous to the present, prompting interest in using these fossil scales as geochemical archives. We investigated the diagenetic characteristics of the two different components of gar scales: ganoine, which has similarities to tooth enamel, and bone. We examined microscopic textural characteristics
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Chemical weathering along a one-million-year soil age gradient on the Galápagos Islands Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-08 Franz Zehetner, Martin H. Gerzabek, J. Gregory Shellnutt, Pei-Hao Chen, I. Nyoman Candra, Kuo-Fang Huang, Der-Chuen Lee
The Galápagos archipelago, a chain of islands formed by hotspot-induced volcanism on the Nazca tectonic plate, exhibits pronounced gradients of rock age and climate. Here, we investigate chemical weathering along a soil chronosequence (1.5 to 1070 ka) and under humid vs. dry conditions. Our results show considerable loss of base cations already in the early to intermediate phases of weathering under
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Silica polymerization and nanocolloid nucleation and growth kinetics in aqueous solutions Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-08 Samuel Scott, Iwona Galeczka, Ingvi Gunnarsson, Stefán Arnórsson, Andri Stefánsson
Amorphous silica precipitation from aqueous solutions at low temperatures (<100 °C) involves the initial nucleation and growth of silica polymers followed by aggregation, cementation and recrystallization to form opaline silica. In this study, silica polymerization was studied at temperature 23–80 °C, pH 2.48–9.65, and ionic strength 0.01–0.53 mol kg. Measured changes in the concentration of monomeric
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Trace elements in coralline algae as a new proxy for seawater chemistry and metal pollution Chem. Geol. (IF 3.9) Pub Date : 2024-03-08 Jean-Alix Barrat, Laurent Chauvaud, Erwan Amice, Jacques Grall, Marie-Laure Rouget, Germain Bayon, Yoan Germain
The abundances of some macronutrients, and trace elements (K, Al, P, V, Mn, Co, Ni, Cu, Zn, Rb, Sr, Mo, Cs, Ba, Pb, Th, U, Y and REE) were determined in a series of coralline algae () samples ( = 101) collected alive in the Bay of Brest and the Iroise Sea (Western Brittany, NW France), in order to assess the potential of these algae as archives of seawater chemistry and potential metal pollution. REY
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Isomorphic substitution behavior of Pt on synthetic vernadite (δ-MnO2):A model reaction to elucidate the mechanism of Pt enrichment in marine ferromanganese crust Chem. Geol. (IF 3.9) Pub Date : 2024-03-08 Zhengkun Li, Xiaoming Sun, Dengfeng Li, Fei Huang, Yongjia Liang
Marine ferromanganese crusts are considered to be the potential Pt deposits, and recent studies report a strong association between Pt and vernadite in these crusts. However, there are still uncertainties regarding the molecular processes involved in the enrichment of Pt by vernadite. This study investigates the adsorption behavior and molecular-scale immobilization mechanisms of Pt at water/vernadite
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Nitrogen isotope gradient on continental margins during the late Paleoproterozoic Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-07 Kento Motomura, Andrey Bekker, Wouter Bleeker, Minoru Ikehara, Takashi Sano, Carl Guilmette, Ying Lin, Shoichi Kiyokawa
The late Paleoproterozoic was a key period in the evolution of Earth’s surface environments and life. It is generally accepted that during the 2.43–2.06 Ga Great Oxidation Episode, the atmospheric oxygen level rose to an intermediate state (0.1 % to 10 % of the present atmospheric level) and the chemical composition of the oceans changed significantly. The paleontological record indicates that eukaryotes
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Short chain tricyclic terpanes as organic proxies for paleo-depositional conditions Chem. Geol. (IF 3.9) Pub Date : 2024-03-07 Hong Xiao, Meijun Li, Benjamin J. Nettersheim
Reconstructing the paleo-environmental conditions that prevailed during the deposition of sediments provides invaluable information for paleo-ecological and evolutionary reconstructions and petroleum exploration. However, reconstructions of depositional environments based on sedimentary structures are often ambiguous, in particular if only core or mud chip samples are available. Organic proxies provide
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Drought effects on soil greenhouse gas fluxes in a boreal and a temperate forest Biogeochemistry (IF 4.0) Pub Date : 2024-03-06
Abstract Changing water regimes (e.g. drought) have unknown long-term consequences on the stability and resilience of soil microorganisms who determine much of the carbon and nitrogen exchange between the biosphere and atmosphere. Shifts in their activity could feedback into ongoing climate change. In this study, we explored soil drought effects on soil greenhouse gas (GHG; CO2, CH4, N2O) fluxes over
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Calcium isotope fractionation during tropical weathering of granites Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-06 Bei-Bei Chen, Yongsheng He, Jinlong Ma, Yang Wang, Ze-Ning Wang, Gangjian Wei
Calcium (Ca) is a highly soluble and mobile element during silicate weathering, and its isotopes could be a promising tracer for continental weathering processes. However, it remains controversial whether Ca isotopes fractionate during granitoids’ weathering. Here we investigated Ca isotope fractionation (measured by δCa) behaviours on the weathering profile of the late middle Jurassic Fogang granite
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Nitrogen inventory of iron meteorite parent bodies constrained by nitrogen partitioning between Fe-rich solid and liquid alloys Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-06 Debjeet Pathak, Rajdeep Dasgupta
Delivery of nitrogen (N), one of the most important elements for life, to Earth thought to have occurred via both undifferentiated and differentiated bodies, lasting at least 50-100 Ma from the birth of the Solar System. Therefore, to understand how Earth got its N, it is imperative to know the N budget of the earliest formed bodies in our Solar System. The best astromaterials available for providing
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Pyrochlore composition and Sm[sbnd]Nd isotope signature as indicators of magmatic-hydrothermal processes: The case of Ririwai complex, north-Central Nigeria Chem. Geol. (IF 3.9) Pub Date : 2024-03-06 Yuxiang Zhu, Lianxun Wang, Yuanming Pan, Chao Zhang, Renat R. Almeev, Zhenbing She, François Holtz
This study presents a geochemical and SmNd isotopic study on pyrochlore from the Ririwai alkaline complex in north-central Nigeria, aiming to reconstruct the magmatic-hydrothermal history and provide insights into the formation of niobium deposit hosted in alkaline igneous rocks. Three texturally and compositionally distinct types of pyrochlore (Pcl I, II, and III) are identified. Primary Pcl I grains
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The source and ore-forming processes of post-collisional Qulong porphyry Cu-Mo deposit in Tibet constrained by Mo isotopes Chem. Geol. (IF 3.9) Pub Date : 2024-03-06 Qiqi Xue, Lipeng Zhang, Shuo Chen, Congying Li, Tao Li, Weidong Sun
Porphyry deposits supply most of the world's Cu and Mo resources. Most porphyry deposits are developed in magmatic arcs above subduction zones. However, abundant Miocene porphyry Cu-Mo deposits have been found in the post-collision stage in Tibet, more than ∼30 Myr after the Indian-Eurasian continental collision. The magma source and the enrichment process of ore-forming elements for these post-collision
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Biomarker evidence for wildfire activity in surface soils from Mt. Yulong on the southeastern Tibetan Plateau: Sources and controls Chem. Geol. (IF 3.9) Pub Date : 2024-03-05 Yangzhuang Li, Yan Bai, Chihao Chen, Qinghu Chen, Xiaomin Fang, Xiaoming Liu, Zhijun Liu
Forest fires have become more frequent in many regions throughout the world over recent decades, principally as a result of global warming. Polycyclic aromatic hydrocarbons (PAH) have become recognized as a byproduct of wildfires and an important indicator of ancient wildfires. However, the factors controlling wildfires remain elusive. This study presents analyses of PAH compounds found in 22 surface
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Molecular transformation of petroleum compounds by hydroxyl radicals produced upon oxidation of reduced nontronite Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-04 Yuan Liu, Yahe Zhang, Guo Chen, Yang Li, Qiang Zeng, Jinglong Hu, Dafu Hu, Hailiang Dong
At redox interfaces, the interaction between oxygen and structural Fe(II) in minerals produces hydroxyl radicals (●OH); however, the specific reactivity and mechanisms of oxidation of complex petroleum compounds by ●OH remain poorly understood. This study investigates the interaction mechanisms between ●OH generated from reduced nontronite, an Fe-rich clay mineral (NAu-2), and petroleum compounds by
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Distribution of 3-hydroxy fatty acids in South China Sea since the last deglaciation: Applicability of 3-hydroxy fatty acid-based palaeothermometry Chem. Geol. (IF 3.9) Pub Date : 2024-03-04 Yinwei Xi, Liuyan Wang, Yasong Wang, Huangmin Ge, Mingxing Zhang, Shengjie Ye, Xueqin Zhao, Yunping Xu
3-Hydroxy fatty acids (3-OH-FAs) are biomarkers for Gram-negative bacteria. Recent research has suggested that they could serve as temperature proxies in both terrestrial and marine environments, based on calibrations using modern samples. However, these proxies have been only applied in a speleothem for the Holocene and a short sediment core in the East China Sea for past 58 years, thus more evidence
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Effects of pockmark activity on iron cycling and mineral composition in continental shelf sediments (southern Baltic Sea) Biogeochemistry (IF 4.0) Pub Date : 2024-03-02 Stanisław Kurowski, Katarzyna Łukawska-Matuszewska, Anđela Čović, Dražan Jozić, Aleksandra Brodecka-Goluch
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Geochemical dispersion of gold-bearing quartz veins in the Wadi Abu Khusheiba area in Southern Jordan Geochem. Trans. (IF 2.3) Pub Date : 2024-03-02 Mariam Mosleh, Jasmi Hafiz Abdul Aziz, Muhammad Hatta Roselee, Ahmed Al-Shorman, Mahmoud Al Tamimi, Abdelkarim Alsoudi
This study delves into the geochemical dispersion of gold-bearing quartz veins in the Wadi Abu Khusheiba area, southern Jordan, with a focus on uncovering the complex patterns of mineralization and their geological significance. Employing an in-depth geochemical analysis of 24 rock samples from the region, we identified that these samples are predominantly hosted by oversaturated rhyolitic rocks, characterized
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Iron projectile fractionation processes in siliceous glass from small impact craters Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-02 Aaron J. Cavosie, Phil A. Bland, Noreen J. Evans, Kai Rankenburg, Malcolm P. Roberts, Luigi Folco
Detection of extra-terrestrial geochemical components in melt generated during meteorite impact provides diagnostic evidence that can be used to confirm a hypervelocity impact event, and in some cases, classify the projectile. However, projectile contamination is often present at sub-percent levels, and can be difficult to detect. In contrast, meteoritic abundances in glass from small impact craters
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Calcium isotope variability among ocean islands reveals the physical and lithological controls on mantle partial melting Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-03-01 Zachary T. Eriksen, Stein B. Jacobsen, James M.D. Day, William M. White
Major geodynamic processes, including mantle convection and plate tectonics, govern the exchange of mass between Earth's interior and its surface. These processes drive mass-transfer mechanisms such as partial melting and crustal recycling, which have generated a lithologically and compositionally heterogeneous mantle over time. Ocean island basalts (OIB) directly sample these heterogeneities, making
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Seawater contamination by coring and pore water sampling of marine sediments Chem. Geol. (IF 3.9) Pub Date : 2024-03-01 Bo Barker Jørgensen, Matthias Egger, Mark A. Lever, Hans Røy
Coring of sediments with minimal physical disturbance, and sampling of pore water with minimal contamination from seawater, are critical in marine geochemistry and microbiology. Yet, sediment coring generally causes smearing of sediment down along the inside of the core liner and leaves seawater and fluid mud trapped around the core. This seawater is a source of diffusive or advective exchange of solutes
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Stable hydrogen and oxygen isotope geochemistry of Fe3+-rich, interstratified clay minerals from seafloor hydrothermal sites Chem. Geol. (IF 3.9) Pub Date : 2024-03-01 Fred J. Longstaffe, Javier Cuadros, Joseph R. Michalski, Vesselin Dekov
Chemical and structural complexities in interstratified clay minerals arising from mineral transformations and evolving formation conditions should be recorded in their stable isotope signatures. This paper examines the controls on the stable hydrogen and oxygen isotope compositions of Fe-rich, glauconite-nontronite, talc-nontronite and talc-saponite from submarine hydrothermal sites, with a focus
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Discriminating quartz host rock based on its trace element chemistry using machine learning-a new tool for sedimentary provenance studies Chem. Geol. (IF 3.9) Pub Date : 2024-02-29 Rupashree Saha, Dewashish Upadhyay, Biswajit Mishra
Quartz is one of the most abundant mineral in the continental crust, occurring in a wide variety of igneous, metamorphic, and sedimentary rocks. It incorporates several trace elements such as Ti, Al, Li, Ge, B, and P in its structure during crystallization/precipitation from magma/fluid, which can potentially be used as petrogenetic indicators. Being physically and chemically resilient during sedimentary
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Correlated IR-SEM-TEM studies of three different grains from Ryugu: From the initial material to post-accretional processes Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-28 Alice Aléon-Toppani, Rosario Brunetto, Zélia Dionnet, Stefano Rubino, Donia Baklouti, François Brisset, Maxime Vallet, Eva Heripre, Tomoki Nakamura, Cateline Lantz, Zahia Djouadi, Ferenc Borondics, Christophe Sandt, David Troadec, Obadias Mivumbi, Megumi Matsumoto, Kana Amano, Tomoyo Morita, Hisayoshi Yurimoto, Takaaki Noguchi, Ryuji Okazaki, Hikaru Yabuta, Hiroshi Naraoka, Kanako Sakamoto, Shogo Tachibana
In order to better constrain the alteration history of the Ryugu parent body, we performed a multi-analytical study combining scanning electron microscopy, transmission electron microscopy and infrared spectroscopy on sections extracted from the three fragments A0064-FO019, A0064-FO021 and C0002-FO019 returned from Ryugu by the Hayabusa2 space mission. The three sections show large differences in terms
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The influence of peritectic garnets on magnesium isotopic composition during crustal anatexis: Constraints from TTG-like leucosomes from the North Qaidam orogen, China Chem. Geol. (IF 3.9) Pub Date : 2024-02-28 Lintao Wang, Shengyao Yu, Dongyong Li, Guozheng Sun, Chuanzhi Li, Yinbiao Peng, Xiaocong Jiang, Xingzhou Jiang, Long Chen, Xiaohui Li, Yongjiang Liu, Sanzhong Li
Tonalitic–trondhjemitic–granodiorite (TTG)-like leucosomes, which are formed from anatectic melts, record crustal growth and evolution and thus provide constraints on the process of anatexis. However, potential Mg isotope disequilibrium during crustal anatexis makes interpreting the genesis of anatectic melts challenging, thereby potentially hindering the application of the Mg isotope system in investigations
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SPORA, a new silver phosphate precipitation protocol for oxygen isotope analysis of small, organic-rich bioapatite samples Chem. Geol. (IF 3.9) Pub Date : 2024-02-28 Gabriele Larocca Conte, Lauren E. Lopes, Aric H. Mine, Robin B. Trayler, Sora L. Kim
Isotopic analysis of phosphate oxygen from bones and teeth (O/O, δO) is a common tool used to investigate modern and ancient ecosystems and their climate. However, existing methods have expanded to use pretreatments for organic removal, require large sample sizes, or require extended precipitation timing. All together, these factors could affect accuracy and precision of δO measurement by promoting
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Isotope fractionation of alkaline and alkaline-earth elements (Li, K, Rb, Mg, Ca, Sr, Ba) during diffusion in aqueous solutions Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-25 Weiqiang Li, Zhihan Ji, Xianglong Luo, Yuqi Li
In this study, we used an improved “diffusion cell” method to precisely determine the diffusion-driven kinetic isotope fractionation factors of the Li, K, Rb, Mg, Ca, Sr, and Ba cations in aqueous solutions under room temperature. The obtained isotope fractionation factors (±2σ errors) are, α = 0.996139 ± 0.000140, α = 0.998572 ± 0.000072, α = 0.999333 ± 0.000020, α = 0.999877 ± 0.000010, α = 0.999704
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Quantifying denudation rates and sediment recycling of low-relief, high-elevation landscapes using in-situ and meteoric cosmogenic nuclides Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-25 Ye Yang, Shun-Cheng Zhang, Jia-Xin Zhang, Li-Feng Cui, Cong-Qiang Liu, Sheng Xu
Quantifying Earth’s surface denudation rates is crucial for estimating sediment flux and its role in regulating global climate change. The inability of in-situ cosmogenic Be to quantify denudation rates in quartz–free environment has prompted the need for a new proxy–the ratio of meteoric Be to mineral-weathered Be in reactive phase (precipitated in or adsorbed onto secondary minerals). This study
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Controls on pyrite sulfur isotopes during early diagenesis in marine sediments of the South China Sea Chem. Geol. (IF 3.9) Pub Date : 2024-02-25 Xinyu Jiang, Shanggui Gong, Tao Sun, Jörn Peckmann, Gilad Antler, Yu Hu, Xudong Wang, Qianyong Liang, Dong Feng
Understanding the controls on the sulfur isotope compositions of syndepositional pyrite (δS) during early diagenesis is critical for environmental reconstructions, especially for the reconstruction of the marine sulfur cycle. Commonly, δS values increase with depth in marine sediments; this phenomenon has been extensively studied, fostering the reconstruction of both global and regional depositional
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Comet 81P/Wild 2 dust impactors of Stardust turnip-like tracks analogous to cluster IDPs Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-24 Mingming Zhang, Noël Chaumard, Céline Defouilloy, William O. Nachlas, Donald E. Brownlee, David J. Joswiak, Andrew J. Westphal, Zack Gainsforth, Kouki Kitajima, Noriko T. Kita
We measured oxygen isotope ratios of 16 silicate fragments from seven aerogel tracks (turnip-like type B tracks 77, 149, 172, 191, and 220; carrot-like type A tracks 22 and 175) of the comet 81P/Wild 2 collector from NASA’s Stardust mission using secondary ion mass spectrometry. Thirteen were prepared by ultramicrotomy; three from track 220 were prepared by sputtering resin blocks using a SIMS Kohler
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High-precision analysis of carbon isotopic composition for individual CO2 inclusions via Raman spectroscopy: Addressing issues arising from the laser-heating effects Chem. Geol. (IF 3.9) Pub Date : 2024-02-24 Hao Wang, Wanjun Lu, Wenjing Wang, Qianghao Liu, Junji Yamamoto
The carbon isotopic composition of carbon dioxide fluid inclusions trapped within minerals reflects the origin and evolution of the CO-bearing fluids and melts. Recently, we developed a highly accurate method using Raman spectroscopy to determine the carbon isotopic composition of CO fluid inclusions, by simultaneously collecting CO and hot bands at a controlled temperature, and using the peak height
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Sources of Li isotope bias during SIMS analysis of standard glasses Chem. Geol. (IF 3.9) Pub Date : 2024-02-24 Adam C. Denny, Mindy M. Zimmer, Heather S. Cunningham, Natalie E. Sievers
The Li/Li ratios in fourteen USGS, MPI-DING, and NIST glass reference materials (RMs) were analyzed by LG-SIMS to assess compositional matrix effects, evaluate RM δLi homogeneity, and calculate the useful yield of lithium in silicate glasses. The analyzed RMs cover a range of SiO contents from 45.5 to 75.6% (komatiite to rhyolite), the largest compositional range yet evaluated for δLi matrix effects
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Decoding the signals of sediment weathering: Toward a quantitative approach Chem. Geol. (IF 3.9) Pub Date : 2024-02-24 Yulong Guo, Yalong Li, Kai Deng, Zhongbo Wang, Shouye Yang
In order to better interpret the signals of weathering intensity recorded in terrigenous sediment archives, it is essential to appropriately assess the effects of hydrodynamic sorting and sedimentary recycling. To achieve this, we utilized a compiled dataset of major element geochemistry of river sediments from East Asia to develop a quantitative index for evaluating the extent of quartz enrichment
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CO2 flux from the French Massif Central groundwaters: Modelling and quantitative estimation of the degassing process Chem. Geol. (IF 3.9) Pub Date : 2024-02-24 Lisa Ricci, Francesco Frondini, Daniele Morgavi, Marino Vetuschi Zuccolini, Guillaume Boudoire, Mickael Laumonier, Stefano Caliro, Carlo Cardellini, Artur Ionescu, Alessandra Ariano, Giovanni Chiodini
Passive rift systems are often characterized by CO degassing, witnessed by the presence of mineral and thermal springs, bubbling pools, mofetes. Despite these field manifestations, the quantitative estimation of the CO budget released to the atmosphere from these geodynamic structures is not well constrained. Here, we examine the chemistry of 169 springs, the isotopic composition of the dissolved carbon
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Vertical variations of bacteriohopanepolyols near the Changjiang Estuary waters: Implications for marine hypoxia and bacterial activities Chem. Geol. (IF 3.9) Pub Date : 2024-02-24 Meiling Yin, Liqin Duan, Jinming Song, Jiawei Kan, Huamao Yuan, Xuegang Li, Yingxia Wang
Bacteriohopanepolyols (BHPs) are widespread in bacteria and are used as lipid biomarkers for specific bacterial activities and environmental changes. However, deposition and degradation dynamics of BHPs are still poorly constrained in marine settings, thereby affecting their reliability as biomarkers. Here, we investigated BHPs in the water columns and sediments near the Changjiang Estuary to evaluate
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The onset of fluid-induced alteration of fluorapatite in iron oxide-apatite deposits: Insights from fluorapatite and their monazite inclusions at the Heiyingshan iron deposit, Beishan Metallogenic Belt, Northwest China Chem. Geol. (IF 3.9) Pub Date : 2024-02-23 Yong Yin, Hao Hu, Xiao-Dong Deng, Daniel Harlov, Jian-Wei Li, Zhuang Duan, Zhe-Jian Pan, David R. Lentz
Iron oxide-apatite (IOA) deposits generally undergo extensive late-stage metasomatic overprinting that modifies the texture and geochemistry of the magnetite, apatite, and other ore-forming minerals. However, the onset of metasomatism in IOA deposits worldwide generally remains poorly constrained. The Heiyingshan IOA deposit is located in the Beishan area of the Central Asian Orogenic Belt, NW China
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A discussion on carbon and oxygen isotopes of secondary carbonates in loess-paleosol sequences Chem. Geol. (IF 3.9) Pub Date : 2024-02-23 Xi Luo, Weiguo Liu, Zhisheng An
Although carbon and oxygen isotopic compositions of carbonates are valuable for Quaternary climate reconstruction due to their sensitivity to paleoclimate changes, a comprehensive understanding regarding the formation, factors influencing isotopic variations, and age uncertainties of secondary carbonates in loess deposits remains elusive. This study investigates the microstructure and stable isotopes
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Redox cycling of straw-amended soil simultaneously increases iron oxide crystallinity and the content of highly disordered organo-iron(III) solids Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-22 CHRISTIAN MIKUTTA, MAX NIEGISCH, AARON THOMPSON, RICARDA BEHRENS, LAURA S. SCHNEE, MARTIN HOPPE, REINER DOHRMANN
Iron speciation in soils is influenced largely by its redox state, but the extent of and controls on Fe speciation during recurrent reduction and oxidation events are not fully understood. To investigate the effects of organic matter (OM) inputs and the frequency and duration of redox oscillations on soil Fe speciation, we conducted redox-oscillation experiments with topsoil from a Fluvisol mixed with
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An accurate model for the solubilities of anhydrite in H2O–NaCl solutions at temperatures up to 1073 K, pressures up to 14,000 bar, and mole fractions of NaCl up to 0.3 Chem. Geol. (IF 3.9) Pub Date : 2024-02-22 Qingqing Wang, Lin Zhang, Jiawen Hu, Xunli Shi
An accurate density-based solubility model is established for anhydrite in HO–NaCl solutions, which is valid for temperatures up to 1073 K, pressures up to 14,000 bar, and mole fractions of NaCl () up to 0.3. The isobaric linear dependence of the mineral solubility logarithm on the solvent density logarithm should be a common phenomenon similar to isothermal linear dependence, particularly at relatively
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Cadmium isotope composition of the Earth's mantle inferred from analysis of oceanic basalts and komatiites Chem. Geol. (IF 3.9) Pub Date : 2024-02-22 Gabriel Devos, Frédéric Moynier, John Creech, Deze Liu, Igor S. Puchtel, Martin Bizzarro
Cadmium stable isotope ratios can serve as valuable tracers for biological and geological processes, including nutrients sampling from the surrounding medium, volatilization events, and terrestrial differentiation. However, studies of the isotope fractionation occurring during geological processes require the characterization of the isotope compositions of the different terrestrial reservoirs. Notably
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Tracking element-mineral associations with unsupervised learning and dimensionality reduction in chemical and optical image stacks of thin sections Chem. Geol. (IF 3.9) Pub Date : 2024-02-22 Marco A. Acevedo Zamora, Balz S. Kamber, Michael W.M. Jones, Christoph E. Schrank, Chris G. Ryan, Daryl L. Howard, David J. Paterson, Teresa Ubide, David T. Murphy
In-situ chemical analysis on thin sections is a cornerstone of geochemical research. Despite massive advances in digital image analysis, the interpretation of such data within the optical petrological context of the thin section has largely remained an analogue task in geochemistry. In this contribution, we registered optical and micro-chemical images from large thin section areas. Chemical datasets
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Thermal-gradient-induced isotope fractionation during CO2-O2 triple oxygen isotope exchange Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-18 Yu Wei, Hao Yan, Yongbo Peng, Shanyu Han, Huiming Bao
Triple oxygen isotope (Δ′O) analysis of CO or carbonate is increasingly applied in diverse fields in earth and environmental sciences. One of the widely-used analytical methods for Δ′O of CO is through Pt-catalyzed oxygen isotope exchange between CO and O. However, large inter-laboratory inconsistencies in oxygen isotope fractionation between the two gases have been reported, potentially hindering
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Coupled carbon‑iron‑phosphorus cycling in the Rainbow hydrothermal vent field Chem. Geol. (IF 3.9) Pub Date : 2024-02-17 Kristin Anna Ungerhofer, Oliver Plümper, Martina Preiner, Gert-Jan Reichart, Peter Kraal
Hydrothermal venting has been shown to play a role in the global biogeochemical cycles of three bio-essential elements: iron (Fe), carbon (C) and phosphorus (P). However, our insight into the coupled cycling of Fe and associated C and P in hydrothermal plumes as well as their long-term fate in the underlying sediments remains limited. We present a detailed study, tracing the biogeochemical pathways
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Petrogenesis of a new type of intrusive shergottite: olivine-gabbro Northwest Africa 13227 Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-16 S. Benaroya, J. Gross, P. Burger, M. Righter, T.J. Lapen, S. Eckley
Petrologic investigations of martian meteorite Northwest Africa (NWA) 13227 indicate it is an olivine-gabbroic shergottite, a relatively new shergottite group, which differs from previously described gabbroic shergottites due to relatively high quantities of olivine. NWA 13227 is comprised of phenocrystic, oscillatory-zoned pyroxene and olivine, set in a matrix of maskelynite, Fe-Cr-Ti oxides, phosphates
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Deep mantle cycle of chalcophile metals and sulfur in subducted oceanic crust Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-16 Zongqi Zou, Zaicong Wang, Yi-Gang Xu, Stephen Foley, Huai Cheng, Liang Ma, Xiang Wang, Kang Chen, Zhaochu Hu, Yongsheng Liu, Yanhong Liu
Understanding the subduction-driven recycling of economically important chalcophile metals (e.g., Cu, Au, Ag, and platinum-group elements, PGEs) and volatiles (e.g., sulfur) is critical for assessing models of ore formation. However, whether the sulfide remains stable in recycled altered oceanic crust (AOC) in the mantle is unclear, and the influence of AOC-derived metasomatic agents on the extraction
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The geochemical evolution of basalt Enhanced Rock Weathering systems quantified from a natural analogue Geochim. Cosmochim. Acta (IF 5.0) Pub Date : 2024-02-16 T. Linke, E.H. Oelkers, K. Dideriksen, S.C. Möckel, S. Nilabh, F. Grandia, S.R. Gislason
Substantial quantities of fine-grained basaltic dust have fallen on South Iceland soils over at least the past 3300 years, making this region an ideal natural analogue to define the long-term consequences of current Enhanced Rock Weathering efforts. A relatively pristine South Iceland Gleyic/Histic Andosol, 3 m in height, receiving approximately 1250 mm of rainfall annually was selected for this study