Upwelling-driven biogenic silica accumulation in the Yangtze Sea, South China during Late Ordovician to Early Silurian time: A possible link with the global climatic transitions

Sedimentary Geology, Journal Year: 2024, Volume and Issue: 461, P. 106571 - 106571

Published: Jan. 8, 2024

Language: Английский

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Different controls on the Hg spikes linked the two pulses of the Late Ordovician mass extinction in South China

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: March 25, 2022

The Late Ordovician mass extinction (LOME, ca. 445 Ma; Hirnantian stage) is the second most severe biological crisis of entire Phanerozoic. LOME has been subdivided into two pulses (intervals), at beginning and ending glaciation, LOMEI-1 LOMEI-2, respectively. Although studies suggest a rapid cooling and/or oceanic euxinia as major causes for this extinction, driver these environmental changes still debated. As other Phanerozoic's extinctions, extensive volcanism may have potential trigger glaciation. Indirect evidence intense comes from Hg geochemistry: peaks concentrations found before during LOME, all attributed to global in origin. Here, we present high-resolution mercury (Hg) profiles three study sections, shelf slope transect, on Yangtze Shelf Sea (South China) address origin anomalies across Ordovician-Silurian (O-S) boundary. results show anomaly enrichments middle Katian, late LOMEI-2 Rhuddanian. middle-late Katian Rhuddanian would probably reflect volcanic We find different controls recorded time: i.e., primarily LOMEI-2. Expansion enhanced by fertilization via weathering deposits Middle combined with finally be responsible LOME.

Language: Английский

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Carbon and sulfur isotope variations through the Upper Ordovician and Lower Silurian of South China linked to volcanism

Palaeogeography Palaeoclimatology Palaeoecology, Journal Year: 2021, Volume and Issue: 567, P. 110285 - 110285

Published: Feb. 11, 2021

Language: Английский

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Thinking about the Biodiversity Loss in This Changing World

Geosciences, Journal Year: 2021, Volume and Issue: 11(9), P. 370 - 370

Published: Sept. 3, 2021

Extinction of species has been a recurrent phenomenon in the history our planet, but it was generally outweighed course quite long geological time by appearance new species, except, especially, for five geologically short times when so-called “Big Five” mass extinctions occurred. Could current decline biodiversity be considered as signal an ongoing, human-driven sixth extinction? This note briefly examines some issues related to: (i) The hypothesized extinction rate and magnitude contemporary global loss; (ii) challenges comparing them to background past Big Five events; (iii) considering effects main anthropogenic stressors on ecosystems, including risk emergence pandemic diseases. A comparison between Pleistocene fauna dynamics with present defaunation process cascading recent actions ecosystem structure functioning suggests that habitat degradation, fragmentation, alien introduction are important increasing negative impact exerted anthropogenic-driven climate changes their connected effects. In addition, ecological such urbanization, landscapes, wildlife trade, creating opportunities virus transmission augmenting human contact wild among factors triggering

Language: Английский

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Roller-coaster atmospheric-terrestrial-oceanic-climatic system during Ordovician-Silurian transition: Consequences of large igneous provinces

Geoscience Frontiers, Journal Year: 2023, Volume and Issue: 14(3), P. 101537 - 101537

Published: Jan. 18, 2023

The Ordovician-Silurian transition (OST) hosted profound and frequent changes in the atmospheric-terrestrial-oceanic-climatic system (ATOCS). Previous studies have found contrasting stages for such changes, primarily based on hiatus-interrupted sections. However, dominant driving factors mechanisms reconciling remain controversial. Mercury isotopes, which undergo both mass-dependent mass-independent fractionation, can provide critical insights into deep-time ATOCSs, especially those impacted by large igneous provinces (LIPs) events. Here, we build a high-resolution multi-proxy record of Hg (concentrations isotopic compositions) combined with organic carbon isotopes (δ13Corg) whole-rock geochemical data (including trace elements phosphorus) from continuous cores Yangtze Platform, South China. Our data, reported ones, indicate occurrence LIP eruptions against localized volcanism, four successive, yet ATOCSs during OST. Moreover, identified coupling between two-pulse magmatism extreme each special pCO2, weathering rate, primary productivity, redox condition, climatic mode, biotic evolution. For stage I, first pulse triggered global warming, enhanced terrestrial weathering, oceanic acidification, eutrophication, anoxia, P recycling, thereby widespread deposition black shales. During II, Hirnantian glaciation oxygenation arose intense chemical shale I; slashed facilitated CO2 accumulation. In III, another de-glaciation, ATOCS was largely similar to that I. This led round positive δ13Corg excursion IV. Compared environmental pressure peculiar stage, their transitions might been more devastating triggering prolonged Late Ordovician Mass Extinction (LOME). limited recovery possible later portion I III. study strata OST provides an excellent framework better illuminating LIPs' essential role "roller-coaster" behavior thus crisis pivotal period

Language: Английский

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Decoding the marine biogeochemical cycling of mercury by stable mercury isotopes

Critical Reviews in Environmental Science and Technology, Journal Year: 2023, Volume and Issue: 53(22), P. 1935 - 1956

Published: April 5, 2023

The oceans, serving as some of the most extensive reservoirs mercury (Hg) on Earth, play an essential role in global Hg biogeochemical circulation, a sink for atmospheric deposits and surface runoff while simultaneously emitting to atmosphere. Clarifying mechanisms during cycling marine ecosystems is crucial segment elucidating behavior assessing its risks wildlife humans. stable isotope technique has emerged powerful tool identifying potential sources certain processes Hg. Herein, research advances were reviewed from isotopic tracing perspective, including Hg, fingerprints across various media, applications isotopes pathways, transport, transformation associated with environments. knowledge gaps challenges further discussed development ultratrace level species-specific analytical methods, fractionation reactions processes, integration multiple approaches cross disciplines. These future studies would advance our understanding oceanic environments, authentic function, interactions other cycle, evaluate response environmental changes.

Language: Английский

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Steep oceanic DIC δ13C depth gradient during the Hirnantian Glaciation

Earth-Science Reviews, Journal Year: 2024, Volume and Issue: 255, P. 104840 - 104840

Published: June 12, 2024

Language: Английский

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CO2 buildup drove global warming, the Marinoan deglaciation, and the genesis of the Ediacaran cap carbonates

Precambrian Research, Journal Year: 2022, Volume and Issue: 383, P. 106891 - 106891

Published: Nov. 8, 2022

Language: Английский

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Terrestrial rather than volcanic mercury inputs to the Yangtze Platform (South China) during the Ordovician-Silurian transition

Global and Planetary Change, Journal Year: 2022, Volume and Issue: 220, P. 104023 - 104023

Published: Dec. 22, 2022

Language: Английский

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The role of LIPs in Phanerozoic mass extinctions: An Hg perspective

Earth-Science Reviews, Journal Year: 2023, Volume and Issue: 249, P. 104667 - 104667

Published: Dec. 29, 2023

Language: Английский

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