Remobilization of crustal carbon dominates volcanic arc emissions


Type
Article
Change log
Authors
Turchyn, AV 
Abstract

The flux of carbon into and out of Earth’s surface environment has implications for Earth’s climate and habitability. We compiled a global dataset for carbon and helium isotopes from volcanic arcs and demonstrated that the carbon isotope composition of mean global volcanic gas is considerably heavier, at -3.8 to -4.6 ‰, than the canonical Mid-Ocean-Ridge Basalt value of -6.0 ‰. The largest volcanic emitters outgas carbon with higher δ13C and are located in mature continental arcs that have accreted carbonate platforms, indicating that reworking of crustal limestone is an important source of volcanic carbon. The fractional burial of organic carbon is lower than traditionally determined from a global carbon isotope mass balance and may have varied over geological time, modulated by supercontinent formation and breakup.

Description
Keywords
0403 Geology
Journal Title
Science
Conference Name
Journal ISSN
0036-8075
1095-9203
Volume Title
357
Publisher
American Association for the Advancement of Science
Sponsorship
Alfred P Sloan Foundation (G-2016-20166047)
Natural Environment Research Council (NE/J017930/1)
European Research Council (307582)
This study was supported by the Alfred P. Sloan Foundation and the Deep Carbon Observatory. This work was supported by a European Research Council Starting Investigator Grant (307582) to A.V.T.