Displaced cratonic mantle concentrates deep carbon during continental rifting

James D. Muirhead (), Tobias P. Fischer (), Sarah J. Oliva, Amani Laizer, Jolante van Wijk, Claire A. Currie, Hyunwoo Lee, Emily J. Judd, Emmanuel Kazimoto, Yuji Sano, Naoto Takahata, Christel Tiberi, Stephen F. Foley, Josef Dufek, Miriam C. Reiss and Cynthia J. Ebinger
Additional contact information
James D. Muirhead: Syracuse University
Tobias P. Fischer: University of New Mexico
Sarah J. Oliva: Tulane University
Amani Laizer: University of Dar es Salaam
Jolante van Wijk: New Mexico Institute of Mining and Technology
Claire A. Currie: University of Alberta
Hyunwoo Lee: Seoul National University
Emily J. Judd: Syracuse University
Emmanuel Kazimoto: University of Dar es Salaam
Yuji Sano: University of Tokyo
Naoto Takahata: University of Tokyo
Christel Tiberi: Géosciences Montpellier, CNRS, Université de Montpellier
Stephen F. Foley: Macquarie University
Josef Dufek: University of Oregon
Miriam C. Reiss: Goethe University Frankfurt
Cynthia J. Ebinger: Tulane University

Nature, 2020, vol. 582, issue 7810, 67-72

Abstract: Abstract Continental rifts are important sources of mantle carbon dioxide (CO2) emission into Earth’s atmosphere1–3. Because deep carbon is stored for long periods in the lithospheric mantle4–6, rift CO2 flux depends on lithospheric processes that control melt and volatile transport1,3,7. The influence of compositional and thickness differences between Archaean and Proterozoic lithosphere on deep-carbon fluxes remains untested. Here we propose that displacement of carbon-enriched Tanzanian cratonic mantle concentrates deep carbon below parts of the East African Rift System. Sources and fluxes of CO2 and helium are examined over a 350-kilometre-long transect crossing the boundary between orogenic (Natron and Magadi basins) and cratonic (Balangida and Manyara basins) lithosphere from north to south. Areas of diffuse CO2 degassing exhibit increasing mantle CO2 flux and 3He/4He ratios as the rift transitions from Archaean (cratonic) to Proterozoic (orogenic) lithosphere. Active carbonatite magmatism also occurs near the craton edge. These data indicate that advection of the root of thick Archaean lithosphere laterally to the base of the much thinner adjacent Proterozoic lithosphere creates a zone of highly concentrated deep carbon. This mode of deep-carbon extraction may increase CO2 fluxes in some continental rifts, helping to control the production and location of carbonate-rich magmas.

Date: 2020
References: Add references at CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/s41586-020-2328-3 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:582:y:2020:i:7810:d:10.1038_s41586-020-2328-3

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-020-2328-3

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().