Late Early Triassic climate change: Insights from carbonate carbon isotopes, sedimentary evolution and ammonoid paleobiogeography

AbstractThe Arda River marine succession (Italy) is an excellent site to apply an integrated approach to paleoenvironmental reconstructions, combining the results of sedimentology, body fossil paleontology, and ichnology to unravel the sedimentary evolution of a complex marine setting in the frame of early Pleistocene climate change and tectonic activity. The succession represents a subaqueous extension of a fluvial system, originated during phases of advance of fan deltas affected by high-density flows triggered by river floods, and overlain by continental conglomerates, indicating a relative sea level fall and the establishment of a continental environment. An overall regressive trend is observed through the section, from prodelta to delta front and intertidal settings. The hydrodynamic energy and the sedimentation rate are not constant through the section, but they are influenced by hyperpycnal flows, whose sediments were mainly supplied by an increase in Apennine uplift and erosion, especially after 1.80 Ma. The Arda section documents the same evolutionary history of coeval successions in the Paleo-Adriatic region, as well as the climatic changes of the early Pleistocene. The different approaches used complement quite well one another, giving strength and robustness to the obtained results.

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Mushrooms Could Provide a Record of Grassland History

Eos ◽

10.1029/2017eo070667 ◽

2017 ◽

Author(s):

Alexandra Branscombe

Keyword(s):

Climate Change ◽

Carbon Isotopes

Scientists measured carbon isotopes in certain types of fungi to assess whether the organisms can track how climate change is affecting grasses.

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Early Triassic fluctuations of the global carbon cycle: New evidence from paired carbon isotopes in the western USA basin

Global and Planetary Change ◽

10.1016/j.gloplacha.2017.05.005 ◽

2017 ◽

Vol 154 ◽

pp. 10-22 ◽

Cited By ~ 13

Author(s):

Gwénaël Caravaca ◽

Christophe Thomazo ◽

Emmanuelle Vennin ◽

Nicolas Olivier ◽

Théophile Cocquerez ◽

...

Keyword(s):

Carbon Cycle ◽

Carbon Isotopes ◽

Global Carbon Cycle ◽

Early Triassic ◽

Western Usa ◽

New Evidence ◽

Global Carbon

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Stable carbon isotopes, C3–C4 vegetation, and 12,800years of climate change in central New Mexico, USA

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2012.10.034 ◽

2013 ◽

Vol 369 ◽

pp. 272-281 ◽

Cited By ~ 20

Author(s):

Stephen A. Hall ◽

William L. Penner

Keyword(s):

Climate Change ◽

New Mexico ◽

Carbon Isotopes ◽

Stable Carbon Isotopes ◽

Stable Carbon

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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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Baghuk Mountain (Central Iran): high-resolution stratigraphy of a continuous Central Tethyan Permian–Triassic boundary section

Fossil Record ◽

10.5194/fr-24-171-2021 ◽

2021 ◽

Vol 24 (1) ◽

pp. 171-192

Author(s):

Dieter Korn ◽

Lucyna Leda ◽

Franziska Heuer ◽

Hemen Moradi Salimi ◽

Elham Farshid ◽

...

Keyword(s):

High Resolution ◽

Carbon Isotope ◽

Carbon Isotopes ◽

Central Iran ◽

Early Triassic ◽

Late Permian ◽

Triassic Boundary ◽

New Name ◽

Permian Triassic Boundary

Abstract. Permian–Triassic boundary sections at Baghuk Mountain (Central Iran) are investigated with respect to their lithological succession, biostratigraphy (particularly conodonts, nautiloids and ammonoids) as well as chemostratigraphy (carbon isotopes). The rock successions consist of the Late Permian Hambast Formation, the youngest Permian Baghuk Member (new name for the “Boundary Clay”) and the Early Triassic Claraia beds. Correlation of the data allows the establishment of a high-resolution stratigraphy based on conodonts with seven Changhsingian zones. Abundant ammonoids enable the separation of ammonoid assemblages with the successive Wuchiapingian genera Prototoceras, Pseudotoceras and Vedioceras, as well as the Changhsingian genera Shevyrevites, Paratirolites, Alibashites, Abichites and Arasella. Griesbachian and Dienerian ammonoids are usually poorly preserved. Nautiloids occur predominantly in the Wuchiapingian part of the section with two successive assemblages dominated by the Liroceratidae and Tainoceratidae, respectively. Numerous Early Triassic strata contain microbialites of various outer morphology and microstructure. The carbon isotope curve (δ13Ccarb) shows a continuous late Changhsingian negative excursion continuing across the Baghuk Member with the lightest values at the base of the Triassic.

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Response Mechanism of Sediment Organic Matter of Plateau Lakes in Cold and Arid Regions to Climate Change: a Case Study of Hulun Lake, China

10.21203/rs.3.rs-1041618/v1 ◽

2021 ◽

Author(s):

Wenwen Wang ◽

Li Zhao ◽

Wei Li ◽

Junyi Chen ◽

Shuhang Wang

Keyword(s):

Climate Change ◽

Organic Matter ◽

Feedback Mechanism ◽

Sediment Organic Matter ◽

Sedimentary Evolution ◽

Terrestrial Source ◽

Nitrogen Ratio ◽

Hulun Lake ◽

Extractable Organic Matter

Abstract Lake organic matter is one of the important forms of terrestrial carbon, and its sedimentary evolution is affected by many factors such as climate and source. However, few studies have been conducted on the bidirectional feedback mechanism between the sedimentary evolution of organic matter and climate change in cold and arid lakes. Historical variations of the sediment organic matter (SOM) and source construction of Hulun Lake, a typical lake in the cold and arid region of China, were studied by multiple methods. The interactions and feedback mechanisms between the sedimentary evolution, climate change, and source construction change were also discussed. Overall, the characteristic indexes of the SOM showed obvious and uniform characteristics of periodical changes. The indexes were relatively stable before 1920, and fluctuated from 1920 to 1979. Since the 1980s, the total organic carbon, carbon stable isotope, and fluorescence intensity of the protein-like component in the water extractable organic matter in the SOM has increased, while the carbon to nitrogen ratio decreased. The absolute dominant contribution of terrestrial source to the SOM had changed, and the relative average contribution rate of autochthonous source increased from 17.6% before 1920 to 36.9% after 2000. The increase of temperature, strong evaporation concentration effect, and the source construction change are the important driving factors of the sedimentary evolution of organic matter in Hulun Lake.

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