The Eurasian epicontinental sea was an important carbon sink during the Palaeocene-Eocene thermal maximum

Mustafa Y Kaya (1, 2) , Guillaume Dupont-Nivet (3, 2) , Joost Frieling (4) , Chiara Fioroni (5) , Alexander Rohrmann (6) , Sevinç Özkan Altıner (1) , Ezgi Vardar (1) , Hakan Tanyaş (7) , Mehmut Mamtimin (8) , Guo Zhaojie

1 METU - Middle East Technical University [Ankara]
2 University of Potsdam = Universität Potsdam
3 GR - Géosciences Rennes
4 Universiteit Utrecht / Utrecht University [Utrecht]
5 UNIMORE - Università degli Studi di Modena e Reggio Emilia = University of Modena and Reggio Emilia
6 Freie Universität Berlin
7 University of Twente
8 Key Lab Orogen Belts and Crustal Evolution [Beijing]

The Eurasian Epicontinental Sea sequestered 720-1300 Gt of organic carbon during the Palaeocene-Eocene Thermal Maximum, according to a palaeogeographic reconstruction and multi-proxy data from a sedimentary sequence in the Tarim Basin, China. The Palaeocene-Eocene Thermal Maximum (ca. 56 million years ago) offers a primary analogue for future global warming and carbon cycle recovery. Yet, where and how massive carbon emissions were mitigated during this climate warming event remains largely unknown. Here we show that organic carbon burial in the vast epicontinental seaways that extended over Eurasia provided a major carbon sink during the Palaeocene-Eocene Thermal Maximum. We coupled new and existing stratigraphic analyses to a detailed paleogeographic framework and using spatiotemporal interpolation calculated ca. 720-1300 Gt organic carbon excess burial, focused in the eastern parts of the Eurasian epicontinental seaways. A much larger amount (2160-3900 Gt C, and when accounting for the increase in inundated shelf area 7400-10300 Gt C) could have been sequestered in similar environments globally. With the disappearance of most epicontinental seas since the Oligocene-Miocene, an effective negative carbon cycle feedback also disappeared making the modern carbon cycle critically dependent on the slower silicate weathering feedback.

Domaines: Climatologie; Stratigraphie

Mustafa Y Kaya, Guillaume Dupont-Nivet, Joost Frieling, Chiara Fioroni, Alexander Rohrmann, et al.. The Eurasian epicontinental sea was an important carbon sink during the Palaeocene-Eocene thermal maximum. Communications Earth & Environment, 2022, 3 (1), pp.124. ⟨10.1038/s43247-022-00451-4⟩. ⟨insu-03696476⟩