Marine biogeochemical nitrogen cycling through Earth’s history

Nature Reviews Earth & Environment, Год журнала: 2024, Номер 5(10), С. 732 - 747

Опубликована: Сен. 24, 2024

Язык: Английский

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Duration of Sturtian “Snowball Earth” glaciation linked to exceptionally low mid-ocean ridge outgassing

Geology, Год журнала: 2024, Номер 52(4), С. 292 - 296

Опубликована: Фев. 7, 2024

Abstract The Sturtian “Snowball Earth” glaciation (ca. 717–661 Ma) is regarded as the most extreme interval of icehouse climate in Earth’s history. exact trigger and sustention mechanisms for this long-lived global remain obscure. widely debated causes are silicate weathering ca. 718 Ma Franklin large igneous province (LIP) changes length degassing continental arcs. A new generation two independent Neoproterozoic full-plate tectonic models now allows us to quantify role tectonics initiating sustaining glaciation. We find that arc remains relatively constant from 850 until end both unlikely play a role. plate motion diverge their predictions timing progression Rodinia break-up, ocean-basin age, ocean-basement depth, sea-level evolution, mid-ocean ridge (MOR) carbon outflux. One model predicts MOR outflux ocean basin volume–driven sea level lower than during Late Cenozoic glaciation, while other outgassing exceeding those Cretaceous hothouse climate. second would preclude major first implies could have been combination an extremely low (~9 Mt C/yr) LIP weathering. Such minimal maintained state 57 m.y. when was markedly reduced, with gradual build-up CO2 atmosphere paired terrestrial volcanism leading its termination.

Язык: Английский

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Evaluating Depositional Environment and Organic Matter Accumulation of Datangpo Formation in Central Hunan Province, South China

Minerals, Год журнала: 2025, Номер 15(4), С. 366 - 366

Опубликована: Март 31, 2025

The interglacial period of the Cryogenian glaciation is a pivotal interval in geological history, marked by two “Snowball Earth” events and emergence early animals. Currently, there considerable debate regarding paleo-oceanic environment dominant factors controlling organic matter enrichment. Here, based on inorganic geochemical data mineral composition from Datangpo Formation Xiangtan (South China), combined with previous research, we have analyzed paleo-climate, redox condition, seawater restriction, primary productivity across different sedimentary facies during this critical interval. results exhibit that can be divided into three members (Da1–Da3) lithology. Paleoclimatic proxies suggest was relatively cold deposition Da-1 Member, while it warm humid Da 2–3 members. Compared to shallow water areas, deep-water areas experienced more rapid transition paleotemperature following Sturtian event. Combining Mo-U elements, CeN/Ce*N, Corg/P ratios, characterized an oxic Formation, then gradually transitioned suboxic, finally anoxic conditions. Furthermore, decompression terrestrial magma chambers led intense volcanic/hydrothermal activity deglaciation period. Hydrothermal most depositional period, followed Da-2, declined Da-3 not only provided essential materials for formation Mn carbonate ores but also significantly enhanced introducing large amounts nutrients paleo-ocean. indicators (Ni/Al, Cu/Al) exhibited obvious coupling CeN/Ce*N ratios indicating oxygen-rich environments were favorable biological proliferation, thereby providing abundant matter. Anoxic conditions further facilitated preservation matter, which may factor driving enrichment Formation.

Язык: Английский

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Evidence for low sulfate and anoxic deep waters in early Cambrian

Palaeogeography Palaeoclimatology Palaeoecology, Год журнала: 2024, Номер 648, С. 112281 - 112281

Опубликована: Май 24, 2024

Язык: Английский

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Primary productivity recovery and shallow-water oxygenation during the Sturtian deglaciation in South China

Global and Planetary Change, Год журнала: 2024, Номер 241, С. 104546 - 104546

Опубликована: Авг. 23, 2024

Язык: Английский

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Multiple S-isotopic evidence for seawater incursions during the deposition of the upper Cretaceous source rocks in the Songliao Basin, northeastern China

Chemical Geology, Год журнала: 2023, Номер 642, С. 121790 - 121790

Опубликована: Окт. 27, 2023

Язык: Английский

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Dynamic evolution of marine productivity, redox, and biogeochemical cycling track local and global controls on Cryogenian sea-level change

Geochimica et Cosmochimica Acta, Год журнала: 2023, Номер 365, С. 114 - 135

Опубликована: Дек. 7, 2023

The Cryogenian period of the Neoproterozoic was marked by two Snowball Earth glaciations that bookended a non-glacial interval lasted roughly 10 million years. break-up Rodinia in early gave rise to numerous rift basins whose time-varying redox dynamics, linked marine productivity and biogeochemical cycling, were likely controlled varying degrees basin restriction response sea-level change. Those drivers associated with both global (Sturtian deglaciation possibly onset Marinoan) local tectonics (regional uplift/subsidence). To explore these relationships, we focus on Datangpo Formation, an exceptional shale sequence deposited marginal South China. succession comprises lower organic-rich black shales upper organic-lean gray shales/siltstones. As elucidated our integrated data, former H2S-rich, deep-water settings underlying highly productive surface waters. We attribute this elevated nutrient supplies replenished from open ocean following rise, as augmented high terrestrial input phosphate wake Sturtian deglaciation. By contrast, shales/siltstones relatively shallow deposition oxic/suboxic water column suppressed primary production. major driver dramatic shift chemistry may lie greater extent isolation corresponding reduction fluxes due significant fall—possibly regional uplift. At time, experienced influx detrital clays organic material, perhaps triggered sea level. Surprisingly, found euxinic conditions prevailed for substantial more isolated conditions. This relationship can be attributed redox-dependent phosphorus cycling. Specifically, H2S-replete facilitated regeneration bioavailable phosphorus, initiating positive feedback allowed persistence anoxic study advances understanding cycling evolution during under influence large-scale fluctuations connectivity must have been common many at time. Furthermore, sheds novel light iron proxy sulfur Almost all silicate-bound converted into reactive phases strong chemical weathering, while data revealed isotopic stratification deglaciation, important messages interpretations analogous aftermath other climate upheavals history.

Язык: Английский

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Carbon and sulfur cycling across the Silurian-Devonian boundary in the Qujing Basin, South China

Chemical Geology, Год журнала: 2024, Номер 648, С. 121952 - 121952

Опубликована: Янв. 21, 2024

Язык: Английский

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Termination of Sturtian glaciation with protracted, multiple volcanic eruptions

Earth-Science Reviews, Год журнала: 2024, Номер 255, С. 104826 - 104826

Опубликована: Июнь 13, 2024

Язык: Английский

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Climatic-hydrologic influence on redox condition in the Cryogenian interglacial Nanhua Basin: Insights from the Datangpo Formation in the northwestern Yangtze Block, South China

Precambrian Research, Год журнала: 2024, Номер 412, С. 107557 - 107557

Опубликована: Сен. 1, 2024

Язык: Английский

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