Structure of the carbon isotope excursion in a high-resolution lacustrine Paleocene–Eocene Thermal Maximum record from central China

Abstract The Pliensbachian–Toarcian boundary interval is characterized by a ~3‰ negative carbon-isotope excursion (CIE) in organic and inorganic marine and terrestrial archives from sections in Europe, such as Peniche (Portugal) and Hawsker Bottoms, Yorkshire (UK). A new high-resolution organic-carbon isotope record, illustrating the same chemostratigraphic feature, is presented from the Southern Hemisphere Arroyo Chacay Melehue section, Chos Malal, Argentina, corroborating the global significance of this disturbance to the carbon cycle. The negative carbon-isotope excursion, mercury and organic-matter enrichment is accompanied by high-resolution ammonite and nannofossil biostratigraphy together with U-Pb CA-ID-TIMS geochronology derived from intercalated volcanic ash beds. A new age of ~183.71 ± 0.40/-0.51 Ma for the Pliensbachian–Toarcian boundary, and 182.77 +0.11/-0.21 for the tenuicostatum–serpentinum zonal boundary, is assigned based on high-precision U-Pb zircon geochronology and a Bayesian Markov chain Monte Carlo (MCMC) stratigraphic age model.

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Dynamics of a stepped carbon-isotope excursion: Ultra high-resolution study of Early Toarcian environmental change

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2011.12.021 ◽

2012 ◽

Vol 319-320 ◽

pp. 45-54 ◽

Cited By ~ 72

Author(s):

Michaël Hermoso ◽

Fabrice Minoletti ◽

Rosalind E.M. Rickaby ◽

Stephen P. Hesselbo ◽

François Baudin ◽

...

Keyword(s):

High Resolution ◽

Environmental Change ◽

Carbon Isotope ◽

Carbon Isotope Excursion ◽

Resolution Study

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Archaeal lipid biomarker constraints on the Paleocene-Eocene carbon isotope excursion

Nature Communications ◽

10.1038/s41467-019-12553-3 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 2

Author(s):

Felix J. Elling ◽

Julia Gottschalk ◽

Katiana D. Doeana ◽

Stephanie Kusch ◽

Sarah J. Hurley ◽

...

Keyword(s):

Isotopic Composition ◽

Carbon Isotope ◽

Carbon Emissions ◽

Membrane Lipids ◽

Geothermal Heating ◽

Surface Ocean ◽

Carbon Isotope Excursion ◽

Thermal Maximum ◽

Lipid Biomarker ◽

Carbon Reservoir

Abstract A negative carbon isotope excursion recorded in terrestrial and marine archives reflects massive carbon emissions into the exogenic carbon reservoir during the Paleocene-Eocene Thermal Maximum. Yet, discrepancies in carbon isotope excursion estimates from different sample types lead to substantial uncertainties in the source, scale, and timing of carbon emissions. Here we show that membrane lipids of marine planktonic archaea reliably record both the carbon isotope excursion and surface ocean warming during the Paleocene-Eocene Thermal Maximum. Novel records of the isotopic composition of crenarchaeol constrain the global carbon isotope excursion magnitude to −4.0 ± 0.4‰, consistent with emission of >3000 Pg C from methane hydrate dissociation or >4400 Pg C for scenarios involving emissions from geothermal heating or oxidation of sedimentary organic matter. A pre-onset excursion in the isotopic composition of crenarchaeol and ocean temperature highlights the susceptibility of the late Paleocene carbon cycle to perturbations and suggests that climate instability preceded the Paleocene-Eocene Thermal Maximum.

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Extending the record of the Lomagundi–Jatuli carbon isotope excursion in the Labrador Trough, Canada

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2019-0198 ◽

2020 ◽

Vol 57 (9) ◽

pp. 1089-1102

Author(s):

Malcolm S.W. Hodgskiss ◽

Kelsey G. Lamothe ◽

Galen P. Halverson ◽

Erik A. Sperling

Keyword(s):

High Resolution ◽

Water Column ◽

Carbon Isotope ◽

Carbon Isotopes ◽

Large Range ◽

Authigenic Carbonate ◽

Elemental Ratios ◽

Carbonate Carbon ◽

Carbon Isotope Excursion ◽

Isotope Analyses

The Labrador Trough in northern Québec and Labrador is a 900 km long Rhyacian–Orosirian orogenic belt containing mixed sedimentary–volcanic successions. Despite having been studied intensively since the 1940s, relatively few chemostratigraphic studies have been conducted. To improve our understanding of the Labrador Trough in the context of Earth history, and better constrain the local record of the Lomagundi–Jatuli carbon isotope excursion, high-resolution sampling and carbon isotope analyses of the Le Fer and Denault formations were conducted. Carbonate carbon isotopes (δ13C) in the Le Fer Formation record a large range in values from −4.4‰ to +6.9‰. This large range is likely attributable to a combination of post-depositional alteration and variable abundance of authigenic carbonate minerals; elemental ratios suggest that the most 13C-enriched samples reflect the composition of the water column at the time of deposition. Cumulatively, these data suggest that the Lomagundi–Jatuli Excursion was ongoing during deposition of the Le Fer Formation, approximately 2 km higher in the stratigraphy than previously recognised. However, the possibility of a post-Lomagundi–Jatuli Excursion carbon isotope event cannot conclusively be ruled out. The directly overlying Denault Formation records a range in δ13C values, from −0.5‰ to +4.3‰, suggesting that it was deposited after the conclusion of the Lomagundi–Jatuli Excursion and that the contact between the Le Fer and Denault formations occurred sometime during the transition out of the Lomagundi–Jatuli Excursion, ca. 2106 to 2057 Ma.

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Diagenetic Attenuation of Carbon Isotope Excursion Recorded by Planktic Foraminifers During the Paleocene-Eocene Thermal Maximum

Paleoceanography and Paleoclimatology ◽

10.1002/2017pa003314 ◽

2018 ◽

Vol 33 (4) ◽

pp. 367-380 ◽

Cited By ~ 9

Author(s):

Reinhard Kozdon ◽

D. Clay Kelly ◽

John W. Valley

Keyword(s):

Carbon Isotope ◽

Carbon Isotope Excursion ◽

Thermal Maximum

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Carbon isotope (δ13Ccarb) and facies variability at the Wenlock–Ludlow boundary (Silurian) of the Midland Platform, UK

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2015-0194 ◽

2016 ◽

Vol 53 (7) ◽

pp. 725-730 ◽

Cited By ~ 5

Author(s):

John A. Blain ◽

David C. Ray ◽

James R. Wheeley

Keyword(s):

High Resolution ◽

Sea Level Rise ◽

Sea Level ◽

Carbon Isotope ◽

Carbonate Platform ◽

Temporal Variations ◽

Spatial Variations ◽

Sea Level Fluctuations ◽

Depositional Settings ◽

Carbon Isotope Excursion

The Wenlock–Ludlow series boundary (Silurian) has been recognized as a time of pronounced sea-level rise and the end of a globally recognized Late Homerian Stage (Mulde) positive carbon isotope excursion (CIE). However, the precise timing and synchronicity of the end of the excursion with respect to the Wenlock–Ludlow boundary is debated. Within the type Wenlock and Ludlow areas (UK), high-resolution δ13Ccarb isotope data are presented across the Wenlock–Ludlow boundary, and within a range of carbonate platform settings. Correlation between sections and depositional settings has been based upon the characteristics of high-order sea-level fluctuations (parasequences). Comparisons between parasequence-bounded δ13Ccarb values reveal clear spatial variations, with lighter values recorded from more distal settings and heavier values from shallower settings. Temporal variations in the δ13Ccarb values are also documented and appear to reflect local variations in carbonate provenance and productivity in response to sea-level rise. While δ13Ccarb values converge in all sections towards the Wenlock–Ludlow boundary, the apparent end of the Mulde CIE appears diachronous and is progressively older within more distal settings.

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