Article
Geochemistry & Geophysics
Dian Ji, Nicholas Dygert
Summary: Plagioclase in lunar anorthositic crust has unusual rare earth element (REE) patterns and Eu abundances that cannot be explained by the solidification of lunar magma ocean (LMO). Subsequent geological processes, such as subsolidus reequilibration after the addition of a minor KREEPy component, can reproduce the REE variations in natural samples. Monte-Carlo simulations suggest that the Moon has a light-REE depleted bulk composition. A post-LMO serial processing model is proposed to explain the petrological, geochronological, and isotopic characteristics of lunar anorthosites and contemporaneous magmatism. Furthermore, it is hypothesized that Earth underwent early differentiation prior to the giant impact event that formed the Moon.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geochemistry & Geophysics
Deze Liu, Frederic Moynier, Paolo A. Sossi, Raphael Pik, Saemundur Ari Halldorsson, Edward Inglis, James M. D. Day, Julien Siebert
Summary: Indium (In) behaves as a moderately volatile metal during nebular and planetary processes and its volatility depends on oxygen fugacity. Accurately determining the isotopic composition of In in silicate Earth is challenging due to its low abundance in rocks and significant isobaric interferences. This study presents a purification procedure for In and reports the first dataset of its isotopic compositions in terrestrial igneous rocks, showing no significant variation between different types of basalts. The average δ115In of 0.35‰ (2SD) in basalts represents the best estimate of the In isotopic composition of the mantle and the bulk silicate Earth.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geochemistry & Geophysics
Shu-Bin Fang, Jian Huang, Xing -Chao Zhang, Dmitri A. Ionov, Zi-Fu Zhao, Fang Huang
Summary: The isotope composition of zinc is an important tracer for planetary formation and differentiation. However, there is still debate about the estimates of the Bulk Silicate Earth and the extent and origin of zinc isotope variations in the mantle. Through analysis of samples from different locations, it was found that there are differences in the zinc content and isotope composition in different minerals, and partial melting has little effect on the zinc isotope composition of the residual mantle.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Geochemistry & Geophysics
Pu Sun, Yaoling Niu, Shuo Chen, Pengyuan Guo, Meng Duan, Yanhong Chen, Hongmei Gong, Yuanyuan Xiao, Xiaohong Wang
Summary: Copper isotope fractionation during magmatic processes has been observed for the first time, with significant fractionation occurring during magma differentiation. The study also found that the fractionation of copper isotopes in magma differentiation is influenced by the redox state and sulfide segregation.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geosciences, Multidisciplinary
Jing-Liang Guo, Zaicong Wang, Wen Zhang, Lanping Feng, Frederic Moynier, Zhaochu Hu, Lian Zhou, Yongsheng Liu
Summary: Zirconium is widely used to trace the differentiation of terrestrial planets and plays a crucial role in zircon, providing constraints on the history of the Earth. Stable Zr isotopes have shown potential in tracing magma differentiation and can reveal zircon crystallization kinetics and magma dynamics. Although the Zr isotope variability and fractionation mechanisms are complex, studies suggest that bulk-rock Zr isotopes can be used to trace the differentiation of felsic magmas. Integrated with other geochemical and isotopic tools, stable Zr isotopes may provide new insight into the dynamic history of diverse igneous systems through time.
EARTH-SCIENCE REVIEWS
(2023)
Article
Geochemistry & Geophysics
Nicolas D. Greber, Thomas Pettke, Nicolas Vilela, Pierre Lanari, Nicolas Dauphas
Summary: Terrestrial and extraterrestrial rocks show significant variations in their mass-dependent Ti isotopic compositions, with basaltic rocks being lighter than evolved lithologies. The measured Ti isotopic compositions in mineral separates and bulk rocks from a volcanic system in Greece reveal two different Ti isotope trends driven by fractional crystallization and mixing between basaltic and rhyolitic magmas. The differences in Ti isotopic compositions in different minerals reflect their equilibrium nature.
Article
Geochemistry & Geophysics
T. E. Johnson, L. J. Morrissey, A. A. Nemchin, N. J. Gardiner, J. F. Snape
Summary: Despite decades of research on the formation and evolution of the Moon, many questions still remain unanswered. Recent thermodynamic models have provided detailed constraints on the compositional, mineralogical, and density structure of the lunar interior, laying the foundation for future research on the origin and evolution of the Moon.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geochemistry & Geophysics
Chun Yang, Sheng-Ao Liu
Summary: In recent years, zinc isotope systematics have been widely used to study mantle heterogeneity and planet formation and evolution in basaltic magmas. The influence of crystal-melt isotope disequilibrium on the zinc isotopic composition of basaltic melts has not received much attention. High-precision zinc isotope data for olivine phenocrysts from alkali basalts in Eastern China suggest diffusion-driven kinetic fractionation during olivine crystallization. The zinc isotope disequilibrium between olivine crystals and melts provides valuable information on the evolution history of intra-plate basaltic magmas.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Multidisciplinary Sciences
Alberto E. Saal, Erik H. Hauri
Summary: The study reveals variations of sulfur isotopes in lunar lavas, indicating several magmatic events during the formation of the Moon.
Article
Astronomy & Astrophysics
Jun Korenaga
Summary: The early evolution of the Earth-Moon system is crucial for understanding the formation and thermal evolution of the Moon. Estimating its early state based on the present suffers from uncertainties related to ocean tides. However, studying tidal evolution during the solidification of Earth's magma ocean can provide robust constraints on the system. We found that energy dissipation during solidification leads to limited lunar recession, suggesting the Moon was still close to the Earth at the end of solidification. This has implications for modeling tidal dissipation in Earth's first billion years and provides new possibilities for resolving the lunar inclination problem.
Article
Geochemistry & Geophysics
Yu Yuan, Jing-Liang Guo, Keqing Zong, Lanping Feng, Zaicong Wang, Frederic Moynier, Wen Zhang, Zhaochu Hu, Haijin Xu
Summary: Stable Zr isotopes have potential in tracing magma differentiation. This study compares the Zr isotopic compositions of the Shidao alkaline complex in China and the Hekla tholeiitic volcanic suite in Iceland, and finds differences in their Zr isotopic evolution paths.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Geosciences, Multidisciplinary
Nan Zhang, Min Ding, Meng-Hua Zhu, Huacheng Li, Haoyuan Li, Zongyu Yue
Summary: This study reveals that the compositional asymmetry between the nearside and farside of the Moon can be explained by impact-induced mantle convection and gravitational instability. Numerical simulations of the South Pole-Aitken impact event and subsequent mantle evolution suggest that the dense KREEP-rich ilmenite-bearing cumulate migrated towards the nearside, resulting in the observed geochemical asymmetry.
Article
Geochemistry & Geophysics
Rzehak J. A. Laura, Kommescher Sebastian, Hoare Liam, Kurzweil Florian, Sprung Peter, Leitzke P. Felipe, Fonseca O. C. Raul
Summary: The fractionation factors of titanium stable isotopes in lunar magmas are different from those in terrestrial magmas due to the reduced conditions on the Moon. Experimental data obtained for common lunar minerals, such as ilmenite, clinopyroxene, and rutile, show that the extent of titanium stable isotope fractionation is significantly influenced by the oxygen fugacity. The new fractionation factors are consistent with ab initio modeling based on density-functional theory. These new data are used to model the solidification of the Lunar Magma Ocean, providing insights into the composition and formation of lunar rocks.
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY
(2022)
Article
Geochemistry & Geophysics
Aleisha C. Johnson, Zhe J. Zhang, Nicolas Dauphas, Roberta L. Rudnick, John D. Foden, Magali Toc
Summary: The isotopic compositions of titanium and iron in lavas and mineral separates from Rindjani Volcano in Indonesia show lower isotopic fractionations compared to other differentiation suites. This is attributed to the dominance of low-Ti magnetite and clinopyroxene as carriers of titanium in Rindjani lavas. The high Fe3+/Fe2+ ratio in calc-alkaline magmas like Rindjani leads to decreased titanium isotopic fractionation. Similarly, negligible iron isotopic fractionation is observed in Rindjani rocks and minerals due to their oxidized nature and similar Fe3+/Fe2+ ratios. Paired titanium and iron isotopic analyses can be a powerful tool for assessing oxygen fugacity during differentiation.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geochemistry & Geophysics
Xiaotong Zhou, Peng Peng, Jing Zhang, Chong Wang
Summary: This study on Mt. Lamington volcano uses texture studies and in-situ chemistry analyses on mineral phenocrysts to reveal the petrogenesis and tectonic settings. The research indicates three components in the volcano, including depleted mantle, enriched mantle, and melts from arc crustal precursors. The spatial negative correlation of Nd-143/Nd-144 ratios from east to west suggests a change in magma sources from depleted mantle to enriched lithospheric mantle with contamination of the Papuan arc crust.
Article
Geochemistry & Geophysics
Wei Dai, Frederic Moynier, Marine Paquet, Julien Moureau, Baptiste Debret, Julien Siebert, Yvan Gerard, Ye Zhao
Summary: This study presents a method for analyzing stable and radiogenic calcium isotopes simultaneously, achieving high precision measurements. The new method opens up new possibilities for research and applications in calcium isotope analysis.
Article
Geochemistry & Geophysics
Caroline R. Soderman, Oliver Shorttle, Simon Matthews, Helen M. Williams
Summary: The geochemistry of global mantle melts shows lithological and temperature heterogeneities from both upper and lower mantle. Non-traditional stable isotopes are suggested as new tools for understanding mantle heterogeneity. Some stable isotope systems can be used as tracers of mantle temperature and lithological heterogeneity, but are not predicted to be sensitive to mantle potential temperature variations with current analytical precision.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Geochemistry & Geophysics
Liam Hoare, Martijn Klaver, Duncan D. Muir, Stephan Klemme, Jane Barling, Ian J. Parkinson, C. Johan Lissenberg, Marc-Alban Millet
Summary: The titanium isotope compositions of different types of rocks, as well as the variations during magmatic differentiation, are discussed in this study. It is found that felsic rocks have heavier titanium isotope compositions compared to mafic rocks, and alkaline magmas have heavier titanium isotope compositions compared to other magma series. The preferential sequestration of light titanium isotopes in Fe-Ti oxides, such as rutile, ilmenite, and titanomagnetite, is suggested as the underlying mechanism for these observations.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Multidisciplinary Sciences
P. Bouilhol, B. Debret, E. C. Inglis, M. Warembourg, T. Grocolas, T. Rigaudier, J. Villeneuve, K. W. Burton
Summary: Hydrated mantle rocks store a significant amount of carbon, both organic and inorganic. During subduction, inorganic carbon is remobilized while organic carbon remains trapped. This has implications for the global carbon cycle.
NATURE COMMUNICATIONS
(2022)
Article
Anthropology
Chris Stantis, Nina Maaranen, Arwa Kharobi, Geoff M. Nowell, Colin Macpherson, Holger Schutkowski, Stephen Bourke
Summary: The site of Pella was a prosperous city-state during the Middle Bronze Age, with extensive socio-economic relationships with Egypt, Cyprus, the Aegean, Anatolia, and Babylonia. Isotopic and ancestry analysis revealed the ancestral background of MBA Pella and the degree of temporary or more permanent relocation from other settlements. This study demonstrates significant movements of populations throughout the Middle Bronze Age evidenced through isotopes and ancestry analysis at Pella.
INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY
(2022)
News Item
Geosciences, Multidisciplinary
Nicolas D. Greber
Summary: The colonization of Earth's landmasses by vascular plants around 430 million years ago had a significant impact on erosion and sediment transport mechanisms, leaving behind evidence in magmatic rocks that links the evolution of Earth's biosphere with its internal processes.
Article
Multidisciplinary Sciences
Baptiste Debret, Benedicte Menez, Bastien Walter, Helene Bouquerel, Pierre Bouilhol, Nadine Mattielli, Celine Pisapia, Thomas Rigaudier, Helen Myfanwy Williams
Summary: Research has found evidence of solid organic compounds rich in organic carbon in the forearc mantle of subduction zones, indicating that slab-derived CO2-rich fluids can be reduced and converted into solid organic compounds.
Article
Geochemistry & Geophysics
Julian -Christopher Storck, Nicolas David Greber, Pierre Lanari, Massimo Tiepolo, Thomas Pettke
Summary: In arc settings, fluid migration and/or differentiation of magmas play important roles in stable-isotope fractionation of elements like molybdenum and titanium. The isotopic compositions of the upper crustal magmatic cumulates and mafic enclaves show variations in titanium isotopes, indicating the degree of Ti isotopic fractionation is controlled by the incorporation of Ti into silicate phases or Fe-Ti oxides. On the other hand, the Mo isotopic compositions of these cumulates and enclaves are more dispersed and similar to average arc-basalts, suggesting that both purely magmatic and predominantly fluid mediated processes contribute to Mo enrichment in cumulates.
Article
Multidisciplinary Sciences
Richard J. M. Taylor, Steven M. Reddy, David W. Saxey, William D. A. Rickard, Fengzai Tang, Caue S. Borlina, Roger R. Fu, Benjamin P. Weiss, Paul Bagot, Helen M. Williams, Richard J. Harrison
Summary: Researchers have discovered magnetite inclusions in zircon grains from the Jack Hills, which potentially carry a record of Earth's magnetic field dating back 4.2 billion years ago. The magnetite may be secondary in nature, suggesting a younger magnetic record than the zircon's crystallization age. The study reveals that the formation of secondary magnetite and the remobilization of lead and iron occurred after 3.4 billion years ago. This finding provides new opportunities to enhance our understanding of the Archean geodynamo. Rating: 9 out of 10.
Article
Multidisciplinary Sciences
Craig R. Walton, Jihua Hao, Fang Huang, Frances E. Jenner, Helen Williams, Aubrey L. Zerkle, Alex Lipp, Robert M. Hazen, Shanan E. Peters, Oliver Shorttle
Summary: Through measurements of preserved rocks, we reconstructed the lithological and chemical evolution of Earth's continental crust. We found a threefold increase in crustal phosphorus (P) concentrations across the Neoproterozoic-Phanerozoic boundary, indicating the progressive concentration of P within the continental crust due to preferential biomass burial. This compositional change was facilitated by the removal of ancient P-poor rock and deposition of young P-rich sediment during a period of enhanced global erosion, leading to increased riverine P fluxes to the ocean. Our results highlight the significance of global erosion and sedimentary P-enrichment in shaping a nutrient-rich crust during the Phanerozoic.
Article
Multidisciplinary Sciences
Caroline R. Soderman, Oliver Shorttle, Esteban Gazel, Dennis J. Geist, Simon Matthews, Helen M. Williams
Summary: This study investigates the lithology and density changes of the Galapagos plume from its head phase to tail using iron stable isotopes and thermodynamic modeling. The findings show that the plume has contained a small, nearly constant amount of dense recycled crust over its 90-million-year history. Despite temporal changes in the amount of recycled crust-derived melt in Galapagos-related lavas, this can be explained by plume cooling alone, without associated changes in the plume's mantle source. The results also support the hypothesis of a plume rooted in a lower mantle low-velocity zone and sampling primordial components.
Article
Geochemistry & Geophysics
Nikitha S. Saji, Roberta L. Rudnick, Richard M. Gaschnig, Marc-Alban Millet
Summary: Titanium isotopes in glacial diamictites from the Paleoproterozoic Nuna and the Neoproterozoic Gondwana supercontinents indicate that the upper continental crust became more felsic during the collision of these supercontinents. The collisional mountain-building of Nuna and Gondwana likely increased the supply of nutrients from continents to oceans. This enhanced nutrient supply may have played a role in the development of organismal complexity and ecological expansion during the Neoproterozoic.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geochemistry & Geophysics
Sarah M. Aarons, Nicolas Dauphas, Nicolas D. Greber, Mathieu Roskosz, Julien Bouchez, Tamara Carley, Xiao-Ming Liu, Roberta L. Rudnick, Jerome Gaillardet
Summary: Stable Ti isotopes have been used to reconstruct the composition of Earth's continental crust. This study investigates the influence of provenance, physical, and chemical weathering on the composition of sediments. The results show that chemical weathering and sediment sorting impact Ti isotopic compositions, but the crustal protolith composition and sorting have a stronger effect than chemical weathering.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Chemistry, Multidisciplinary
Nicolas D. Greber, Kirsten van Zuilen
Summary: The development of multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) allows for high precision and accurate analysis of isotopic compositions of a wide range of elements. This technique has opened up new research avenues and is increasingly applied in various disciplines.
Article
Geochemistry & Geophysics
Lingyu Zhang, Kristoffer Szilas
Summary: This study presents new petrological and geochemical data for the Narssaq Ultramafic Body (NUB) in the Itsaq Gneiss Complex of SW Greenland. The results indicate that the ultramafic rocks of NUB are not mantle residues, but instead represent crustal cumulates derived from high-Mg magmas.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Rong Xu, Sarah Lambart, Oliver Nebel, Ming Li, Zhongjie Bai, Junbo Zhang, Ganglan Zhang, Jianfeng Gao, Hong Zhong, Yongsheng Liu
Summary: This study investigated the iron isotope compositions of Cenozoic basalts in Southeast China, finding significant variations related to different types of basalts and their respective sources.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
C. J. Ebinger, Miriam C. Reiss, Ian Bastow, Mary M. Karanja
Summary: The East African rift system is formed above mantle upwellings and the formation of rifts is related to lithospheric thinning and magmatic activity. The amount of splitting varies spatially and the fast axes are predominantly parallel to the orientation of the rifts. Thick lithospheric modules have less splitting and different orientations, which may indicate mantle plume flow. Splitting rotates and increases in strength as it enters the rift zones, suggesting that the anisotropy is mainly present at shallow depths.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Correction
Geochemistry & Geophysics
Ekaterina Rojas-Kolomiets, Owen Jensen, Michael Bizimis, Gene Yogodzinski, Lukas Ackerman
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Robert W. Nicklas, Igor S. Puchtel, Ethan F. Baxter
Summary: Oxygen fugacity is a fundamental parameter for understanding redox processes in igneous systems. This study compares the Fe-XANES oxybarometry method with the V-in-olivine method for evaluating fO(2) in MORB lavas. The results show that the V-in-olivine method is not applicable to samples with low MgO content, and that the majority of Archean komatiite sources have lower fO(2) than modern MORB.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Chunfei Chen, Stephen F. Foley, Sebastian Tappe, Huange Ren, Lanping Feng, Yongsheng Liu
Summary: The volatile components CO2 and H2O play a major role in mantle melting and heterogeneity. In this study, Ca isotopes were used to trace the lithological heterogeneity in alkaline magmatic rocks. The results revealed the presence of K-richterite and carbonate components as the source of alkaline magmas with low delta 44/40Ca values. These findings highlight the importance of Ca isotopes as a robust tracer of lithological variation caused by volatiles in the Earth's upper mantle.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Timothee Jautzy, Gilles Rixhon, Regis Braucher, Romain Delunel, Pierre G. Valla, Laurent Schmitt, Aster Team
Summary: Although the current approach to estimate catchment-wide denudation rates using only 10Be concentrations has made significant progress in geomorphology, this study argues for the inclusion of 26Al measurements and testing of steady-state assumptions in slow eroding, formerly glaciated landscapes. The study conducted measurements of both 10Be and 26Al in stream sediments from the Vosges Massif in France and found that elevation, slope, channel steepness, and precipitation were the primary factors controlling denudation rates. The study also revealed a significant relationship between the extent of past glaciation and the cosmogenic (un-)steadiness in the stream sediments.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Erik van der Wiel, Douwe J. J. van Hinsbergen, Cedric Thieulot, Wim Spakman
Summary: Numerical models of Earth's mantle dynamics can predict the vigour and mixing of mantle flow, and the average slab sinking rates are an unexplored parameter that can provide intrinsic information on these characteristics. Through numerical experiments, it has been found that slab sinking rates are strongly correlated with mantle convection and mixing, and may explain geochemical observations from hotspot volcanoes.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
