Article
Geochemistry & Geophysics
He Zhao, Jun Shen, Thomas J. Algeo, Grzegorz Racki, Jiubin Chen, Cheng Huang, Junjun Song, Wenkun Qie, Yiming Gong
Summary: This study examines the geographic distribution and stratigraphic range of Late Devonian volcanic inputs, finding that volcanic activity was regional and possibly related to subduction zones and/or a large igneous province in the Paleo-Tethyan region.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Dongping Hu, Menghan Li, Xiaolin Zhang, Xiangdong Wang, James Farquhar, Yilun Xu, Lilin Sun, Yanan Shen
Summary: By analyzing the S-isotopic records from the Naqing section in South China, this study reveals changes in redox conditions in the mid-Carboniferous oceans and suggests that the episodic incursion of toxic anoxic water may have contributed to the Serpukhovian extinction.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Review
Geosciences, Multidisciplinary
Na Li, Chao Li, Thomas J. Algeo, Meng Cheng, Chengsheng Jin, Guangyou Zhu, Junxuan Fan, Zongyuan Sun
Summary: During the Late Ordovician mass extinction, two pulses of faunal mortality occurred as a result of expanded marine euxinia, affecting both inner and outer Yangtze Sea. The less-studied outer Yangtze Sea sections show changes in marine redox conditions, chemical weathering rates, and primary productivity. The contraction and expansion of oceanic euxinia in response to continental weathering intensity and sulfate availability played a significant role in shaping marine redox variations and influencing the biotic crisis during this time period.
EARTH-SCIENCE REVIEWS
(2021)
Article
Geochemistry & Geophysics
Mu Liu, Daizhao Chen, Lei Jiang, Richard G. Stockey, Dan Aseal, Bao Zhang, Kang Liu, Xiangrong Yang, Detian Yan, Noah J. Planavsky
Summary: This study explores the relationship between the Late Ordovician mass extinction and global marine anoxia through uranium isotope analysis. The research reveals that two episodes of widespread marine anoxia occurred during the Late Katian and the mid-late Hirnantian, with varying effects on biotic turnover.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geography, Physical
Junpeng Zhang, Timothy W. Lyons, Chao Li, Xiang Fang, Qing Chen, Joseph Botting, Yuandong Zhang
Summary: Recent studies have linked an oceanic anoxic event during the Hirnantian to the Late Ordovician mass extinction. However, the extent and duration of the event remain uncertain, as well as the impact of oceanic anoxia on marine ecosystems. This study investigates previously unstudied sections in South China to gather data on iron speciation and sulfur isotope signatures, providing a global and local perspective on oceanic redox conditions during this period. The results suggest that glacio-eustatic variation and enhanced pyrite burial contributed to the oxygenation of shallow-water environments, while decreased isotopic fractionation indicates low oceanic sulfate levels. Correlations with marine faunal diversity data suggest that oceanic anoxia may not have been the sole trigger of the mass extinction. Overall, this study contributes new insights into the processes of the Late Ordovician mass extinction and the relationship between oceanic anoxia events and mass extinctions over geological history.
GLOBAL AND PLANETARY CHANGE
(2022)
Article
Geography, Physical
Chengsheng Jin, Zhiwei Liao, Gary G. Lash
Summary: The study suggests that fluctuations in redox conditions, in addition to commonly cited thresholds of bimetal ratios, may have influenced the redox trends during the Ordovician-Silurian transitional interval. The strong correlation between changing redox conditions and fossil distributions implies that dynamic and ferruginous conditions contributed to biotic crises. The coupling of total organic carbon (TOC) and redox proxies highlights the importance of prolonged anoxia or euxinia in the accumulation and preservation of organic matter.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2021)
Article
Geography, Physical
Yangbo Lu, Jun Shen, Yuxuan Wang, Yongchao Lu, Thomas J. Algeo, Shu Jiang, Detian Yan, Qiyang Gou
Summary: The Late Ordovician mass extinction (LOME) occurred in two discrete pulses, linked to environmental stresses caused by the onset and termination of the Hirnantian Glaciation. Recent studies have suggested a potential connection between LOME and massive volcanism during the Ordovician-Silurian transition (OST), based on significant mercury anomalies in the South China region. However, the study finds that volcanic activity in South China during the OST was a regional phenomenon, and there is a discrepancy between the distribution of bentonite beds and the overall redox evolution in the region. Mercury isotope analysis suggests that seawater was the source of mercury enrichment during the OST. Therefore, the LOME may not have been caused by massive volcanism, but rather by long-term cooling, weathering, anoxia, and marine eutrophication.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Wei Tang, Jian Wang, Hengye Wei, Xiugen Fu, Puyang Ke
Summary: This study presents carbonate-associated sulfate (CAS) and pyrite delta S-34 (py) data from the Wenquan Section in the Qiantang Basin, Tibet, for the Late Triassic-Early Jurassic interval. It reveals an 8‰ magnitude Rhaetian positive sulfur isotope excursion (RPSE) and a decrease in the isotopic offset between CAS and pyrite delta S-34 values. Modeling suggests low oceanic sulfate concentrations during this period, supporting the global nature of the Late Triassic oceanic deoxygenation event and its impact on the sulfur cycle.
JOURNAL OF ASIAN EARTH SCIENCES
(2023)
Article
Geochemistry & Geophysics
Ziyao Fang, Xiaoqing He, Guijie Zhang, Xiaolin Zhang, Yanan Shen, Liping Qin
Summary: Research analyzing Cr isotopes in marine rocks in southern China revealed changes in Cr isotope compositions during the late Permian, possibly related to oceanic anoxia. The negative excursion values following the extinction horizon may indicate the expansion of oceanic anoxia, while persistent negative values in the Early Triassic suggest a prolonged recovery period for the ocean.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Biology
Nevin P. Kozik, Seth A. Young, Anders Lindskog, Per Ahlberg, Jeremy D. Owens
Summary: Using multiple proxies, we studied two drill core successions in the Baltic and Scandinavian regions, revealing persistently anoxic and sulfidic bottom water conditions. Trace metal datasets suggest nuanced changes in global anoxic and sulfidic conditions along continental margins. Thallium isotope data indicate a global expansion of oxygenated shelf and deeper marine environments from the late Cambrian into the Early Ordovician. These findings provide evidence for increased marine oxygen concentrations as a key mechanism for the Ordovician radiation of marine life.
Article
Multidisciplinary Sciences
Christopher K. Junium, Aubrey L. Zerkle, James D. Witts, Linda C. Ivany, Thomas E. Yancey, Chengjie Liu, Mark W. Claire
Summary: The study found evidence of mass-independent fractionation of sulfur isotopes in Chicxulub impact ejecta materials, indicating sulfur-bearing gases in the atmosphere after the impact were substantially different from the modern atmosphere. The data suggest that sulfur gases may have originated from stratospheric photolysis of SO2 derived from the target rock or carbonyl sulfide produced by biomass burning, ultimately oxidizing into sulfate aerosols, providing direct evidence for the primary role of sulfate aerosols in post-impact climate change and global mass extinction.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Geography, Physical
Guijie Zhang, Xiaolin Zhang, Dandan Li, Haishui Jiang, Yilun Xu, Menghan Li, Yanan Shen
Summary: The study revealed a global negative C-isotope excursion during the Smithian period, which exhibited a first-order correspondence with global transgression and ocean anoxia. Numerical box modeling suggested that the negative C-isotope excursion could have been triggered by increased organic carbon oxidation in response to the upward movement of anoxic bottom waters. The study provided quantitative constraints on the causal link between the Smithian negative C-isotope excursion and widespread anoxia, potentially impacting the late Smithian extinction and prolonged Early Triassic biotic recovery.
GLOBAL AND PLANETARY CHANGE
(2021)
Article
Geochemistry & Geophysics
Jun Shen, Thomas J. Algeo, Qinglai Feng
Summary: High mercury concentrations in the Ordovician-Silurian transition sections of South China come from the uptake of mercury from seawater. Mercury isotope studies support a marine source, ruling out a volcanic source. Local environmental conditions play a dominant role in mercury enrichment in the South China strata.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Xinze Lu, Cole T. Edwards, Brian Kendall
Summary: This study investigates the role of ocean anoxia/euxinia on the base Stairsian mass extinction event by measuring elemental concentrations and uranium isotope compositions in carbonate samples from three sections in the Great Basin. The results show different uranium isotope trends in the three sections, with the distal sections better preserving global ocean signals. The study suggests that the small mass extinction event was not associated with an expansion of global ocean euxinia.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geography, Physical
Nevin P. Kozik, Seth A. Young, Per Ahlberg, Anders Lindskog, Jeremy D. Owens
Summary: This study utilizes a multiproxy dataset to investigate local and global marine paleoredox dynamics during the Middle-Late Ordovician. The results suggest a transition towards more oxygenated marine environments during this time period, coinciding with global climatic cooling trends.
GLOBAL AND PLANETARY CHANGE
(2023)
Article
Geology
Sara B. Pruss, Martha L. Slaymaker, Emily F. Smith, Andrey Yu Zhuravlev, David A. Fike
Summary: The newly discovered Gold Point Reef in the lower Poleta Formation exhibits differences in reef development stages and ecological stages compared to the Stewart's Mill exposure. The research on the reef identifies three stages of development: pioneer stage, diversification stage, and final foundering stage, each characterized by different species of archaeocyaths and facies reflecting reef demise.
Article
Multidisciplinary Sciences
V Pasquier, R. N. Bryant, D. A. Fike, I Halevy
Summary: Understanding the variations in sulfur isotopic composition of sedimentary pyrite is essential due to the crucial role of sulfur biogeochemistry in regulating the Earth's surface oxidation state. Recent research reveals that local depositional conditions significantly impact the delta S-34(pyr) values, challenging the previous interpretation of stratigraphic variations as global biogeochemical cycling changes. The study demonstrates strong local controls on delta S-34(pyr) and calls for a reevaluation of using these variations to infer global changes in Earth's surface environment.
Article
Geosciences, Multidisciplinary
Cole T. Edwards, Clive M. Jones, Page C. Quinton, David A. Fike
Summary: This study presents 108 new δO-18 values using SIMS from conodont apatite collected from different stratigraphic successions in North America. The results show that SIMS-based δO-18 values are consistent with published trends and provide valuable information for identifying temperature trends that were not possible with bulk approaches. However, there is an offset between SIMS-based values and bulk values, indicating a need for caution when using SIMS for paleo-temperature reconstructions.
GEOLOGICAL SOCIETY OF AMERICA BULLETIN
(2022)
Correction
Biology
Shana K. Goffredi, Cambrie Motooka, David A. Fike, Luciana C. Gusmao, Ekin Tilic, Greg W. Rouse, Estefania Rodriguez
Article
Biology
Maya L. Gomes, Judith M. Klatt, Gregory J. Dick, Sharon L. Grim, Kathryn I. Rico, Matthew Medina, Wiebke Ziebis, Lauren Kinsman-Costello, Nathan D. Sheldon, David A. Fike
Summary: The sedimentary pyrite sulfur isotope record serves as an archive of ancient microbial sulfur cycling and environmental conditions. Analysis reveals that porewater sulfide delta S-34 values fluctuate significantly throughout the day due to light-driven changes in microbial activity.
Article
Geochemistry & Geophysics
Lionel G. Vacher, Ryan C. Ogliore, Clive Jones, Nan Liu, David A. Fike
Summary: This passage discusses the influence of the Sun's astrophysical birth environment on the formation and composition of the Solar System. Analyzing oxygen and sulfur isotopes, it suggests the presence of chemical reactions from ultraviolet sources in the parent molecular cloud of the Solar System, with sulfur isotopes as a more direct probe of this astrophysical environment.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Multidisciplinary Sciences
Virgil Pasquier, David A. Fike, Itay Halevy
Summary: The study demonstrates that variations in sulfur isotope ratios (δS-34(pyr)) in Peruvian margin sediments are influenced by Oxygen Minimum Zone intensification/expansion and organic matter deposition. Higher microbial sulfate reduction rates result in more effective drawdown and S-34-enrichment of residual porewater sulfate and sulfide, which is preserved in pyrite. These findings emphasize the importance of local environmental changes in shaping sulfur isotope ratios.
NATURE COMMUNICATIONS
(2021)
Article
Geosciences, Multidisciplinary
Christian Hallmann, Emmanuelle Grosjean, Nathan D. Shapiro, Yuichiro Kashiyama, Yoshito Chikaraishi, David A. Fike, Naohiko Ohkouchi, Roger E. Summons
Summary: Nitrogen is a key nutrient that influences evolution and Earth history. By studying chlorophyll-derived compounds, insights into nitrogen assimilation in chemoclines can be gained. The contribution of anoxygenic phototrophs to primary productivity may have increased over time.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geochemistry & Geophysics
Jocelyn A. Richardson, Aivo Lepland, Olle Hints, Anthony R. Prave, William P. Gilhooly, Alexander S. Bradley, David A. Fike
Summary: Isotopic profiles of carbon, sulfur, and oxygen in Silurian strata from the Baltoscandian Basin in Estonia during the Ireviken Bioevent reveal local depositional influences superimposed on a global signal. Sulfur isotope records exhibit high stratigraphic variability, affected by local sea level and facies differences. Our findings provide insights into platform-scale evolution and diagenetic processes, offering a mechanism to understand the variability in deep-time sulfur isotope records.
Article
Geochemistry & Geophysics
R. Seth Wood, Aivo Lepland, Ryan C. Ogliore, Jennifer Houghton, David A. Fike
Summary: In this study, authigenic carbonate and barite crusts from cold seeps on the Lofoten-Vesteralen continental slope in northern Norway were analyzed, revealing methane-derived Mg-calcite and aragonite phases. Using microscale sulfur isotope composition measurements, variations in the activity of anaerobic oxidation of methane coupled to sulfate reduction were found to affect sulfate distillation, indicating temporal changes in seep methane flux. The study provides insights into paleo-methane flux and methane advection rates variability during crust formation.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geography, Physical
J. Houghton, D. Scarponi, L. Capraro, D. A. Fike
Summary: The isotopic composition of sulfur in sedimentary pyrite plays a key role in reconstructing global sulfur cycling and Earth's surface oxidation state over Earth history, but recent research has shown its strong dependence on local depositional conditions. The chemostratigraphic record presented in this study allows for differentiation of sedimentary patterns and highlights the influence of global and local environmental factors on the sedimentary record.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Amy P. I. Hagen, David S. Jones, Nicholas J. Tosca, David A. Fike, Sara B. Pruss
Summary: The Steptoean Positive Isotopic Carbon Excursion (SPICE event) is a globally recorded anomaly event during the late Cambrian period, and its mechanisms are not fully understood. Recent studies have shown that the SPICE event is associated with global changes in redox conditions. This study focuses on evaluating local redox conditions during the SPICE in Newfoundland and verifying the validity of using mercury as a redox proxy.
CANADIAN JOURNAL OF EARTH SCIENCES
(2022)
Article
Geochemistry & Geophysics
K. Paiste, D. A. Fike, K. Kirsimae, C. Jones, A. Lepland
Summary: The Paleoproterozoic metasedimentary rocks of the Zaonega Formation in NW Russia provide important information about global environmental changes after the initial oxygenation of the Earth's atmosphere and oceans. This study examines the geochemical signals preserved in these rocks and their environmental meaning, particularly focusing on the unusually high pyrite sulfur isotope ratios. The results show that the formation of pyrite in the Zaonega Formation occurred through multiple stages, and early-stage pyrite has different isotopic signatures compared to late-stage pyrite. The findings suggest that a thorough understanding of the geological context and mechanisms associated with sulfur cycling and pyrite formation is essential for interpreting the isotopic records accurately.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Chemistry, Multidisciplinary
Electra Kotopoulou, Athanasios Godelitsas, Jorg Gottlicher, Ralph Steininger, Roy Price, David A. Fike, Jan P. Amend, William P. Gilhooly, Gregory Druschell, Paraskevi Nomikou, Platon N. Gamaletsos, Stylianos Lozios
Summary: This study investigates the presence and role of metastable iron sulfides in marine sediments from the Milos hydrothermal system. The results show that these metastable iron sulfides play a critical role in sulfur, iron, and carbon cycling in marine sediments, which has previously been overlooked in standard microscopic, spectroscopic, and diffraction techniques. The findings suggest that the importance of metastable iron sulfides in biogeochemical processes in marine ecosystems may have been underestimated.
ACS EARTH AND SPACE CHEMISTRY
(2022)
Article
Geochemistry & Geophysics
V Pasquier, D. A. Fike, S. Revillon, I Halevy
Summary: The study highlights the importance of iron speciation in sediments and sedimentary rocks, and its application in modern and ancient samples. It shows that iron speciation analysis can be used to constrain sediment sources and diagenetic processes, but is rarely indicative of the chemistry and oxidation state of ancient water columns.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
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)