Tracking carbon from subduction to outgassing along the Aleutian-Alaska Volcanic Arc.

Autor: Lopez T; Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA.; Alaska Volcano Observatory, UAF Geophysical Institute, Fairbanks, AK, USA., Fischer TP; University of New Mexico, Albuquerque, NM, USA., Plank T; Lamont Doherty Earth Observatory, Columbia University, Palisades, NY, USA., Malinverno A; Lamont Doherty Earth Observatory, Columbia University, Palisades, NY, USA., Rizzo AL; Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Milano, Milano, Italy.; Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milano, Italy., Rasmussen DJ; Lamont Doherty Earth Observatory, Columbia University, Palisades, NY, USA.; Department of Mineral Sciences, National Museum of Natural History Smithsonian Institution, Washington, DC, USA., Cottrell E; Department of Mineral Sciences, National Museum of Natural History Smithsonian Institution, Washington, DC, USA., Werner C; U.S. Geological Survey Contractor, New Plymouth, New Zealand., Kern C; Cascades Volcano Observatory, U.S. Geological Survey, Vancouver, WA, USA., Bergfeld D; California Volcano Observatory, U.S. Geological Survey, Moffett Field, CA, USA., Ilanko T; University of Waikato, Hamilton, New Zealand., Andrys JL; U.S. Geological Survey Contractor, New Plymouth, New Zealand.; Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA., Kelley KA; Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA.
Jazyk: angličtina
Zdroj: Science advances [Sci Adv] 2023 Jun 28; Vol. 9 (26), pp. eadf3024. Date of Electronic Publication: 2023 Jun 28.
DOI: 10.1126/sciadv.adf3024
Abstrakt: Subduction transports volatiles between Earth's mantle, crust, and atmosphere, ultimately creating a habitable Earth. We use isotopes to track carbon from subduction to outgassing along the Aleutian-Alaska Arc. We find substantial along-strike variations in the isotopic composition of volcanic gases, explained by different recycling efficiencies of subducting carbon to the atmosphere via arc volcanism and modulated by subduction character. Fast and cool subduction facilitates recycling of ~43 to 61% sediment-derived organic carbon to the atmosphere through degassing of central Aleutian volcanoes, while slow and warm subduction favors forearc sediment removal, leading to recycling of ~6 to 9% altered oceanic crust carbon to the atmosphere through degassing of western Aleutian volcanoes. These results indicate that less carbon is returned to the deep mantle than previously thought and that subducting organic carbon is not a reliable atmospheric carbon sink over subduction time scales.
Databáze: MEDLINE