Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle
Growing evidence points to the dynamic role that kerogen is playing on Earth's surface in controlling atmospheric chemistry over geologic time. Although quantitative constraints on the weathering of kerogen remain loose, its changing weathering behavior modulated by the activity of glaciers sug...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/530887 2023-05-15T16:22:29+02:00 Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle Blattmann, Thomas 2022 application/application/pdf https://hdl.handle.net/20.500.11850/530887 https://doi.org/10.3929/ethz-b-000530887 en eng Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-19-359-2022 info:eu-repo/semantics/altIdentifier/wos/000748748900001 http://hdl.handle.net/20.500.11850/530887 doi:10.3929/ethz-b-000530887 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International CC-BY Biogeosciences, 19 (2) info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2022 ftethz https://doi.org/20.500.11850/530887 https://doi.org/10.3929/ethz-b-000530887 https://doi.org/10.5194/bg-19-359-2022 2023-02-13T01:00:32Z Growing evidence points to the dynamic role that kerogen is playing on Earth's surface in controlling atmospheric chemistry over geologic time. Although quantitative constraints on the weathering of kerogen remain loose, its changing weathering behavior modulated by the activity of glaciers suggests that this largest pool of reduced carbon on Earth may have played a key part in atmospheric CO2 variability across recent glacial–interglacial cycles and beyond. This work enunciates the possibility of kerogen oxidation as a major driver of atmospheric CO2 increase in the wake of glacial episodes. This hypothesis of centennial- and millennial-timescale relevance for this chemical weathering pathway is substantiated by several lines of independent evidence synthesized in this contribution, including the timing of atmospheric CO2 increase, atmospheric CO2 isotope composition (13C and 14C), kerogen oxidation kinetics, observations of kerogen reburial, and modeling results. The author hypothesizes that the deglaciation of kerogen-rich lithologies in western Canada contributed to the characteristic deglacial increase in atmospheric CO2, which reached an inflection point ≤ 300 years after the Laurentide Ice Sheet retreated into the kerogen-poor Canadian Shield. To reconcile the release of isotopically light carbon via kerogen oxidation with Earth surface carbon pool constraints, major oceanic degassing and biospheric regrowth must have acted in concert across glacial–interglacial transitions. Additionally, a process such as a strong shift in the ratio of C3 to C4-derived organic matter must be invoked to maintain isotope mass balance, a point key for reconciling the hypothesis with the carbon isotope record of marine dissolved inorganic carbon. In order to test this hypothesis, quantitative constraints on the contribution of kerogen oxidation to CO2 rise at glacial terminations are needed through systematic studies on (1) CO2 fluxes emanating from the weathering of different lithologies, (2) oxidation kinetics of kerogen ... Article in Journal/Newspaper glacier* Ice Sheet ETH Zürich Research Collection Canada |
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Open Polar |
collection |
ETH Zürich Research Collection |
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ftethz |
language |
English |
description |
Growing evidence points to the dynamic role that kerogen is playing on Earth's surface in controlling atmospheric chemistry over geologic time. Although quantitative constraints on the weathering of kerogen remain loose, its changing weathering behavior modulated by the activity of glaciers suggests that this largest pool of reduced carbon on Earth may have played a key part in atmospheric CO2 variability across recent glacial–interglacial cycles and beyond. This work enunciates the possibility of kerogen oxidation as a major driver of atmospheric CO2 increase in the wake of glacial episodes. This hypothesis of centennial- and millennial-timescale relevance for this chemical weathering pathway is substantiated by several lines of independent evidence synthesized in this contribution, including the timing of atmospheric CO2 increase, atmospheric CO2 isotope composition (13C and 14C), kerogen oxidation kinetics, observations of kerogen reburial, and modeling results. The author hypothesizes that the deglaciation of kerogen-rich lithologies in western Canada contributed to the characteristic deglacial increase in atmospheric CO2, which reached an inflection point ≤ 300 years after the Laurentide Ice Sheet retreated into the kerogen-poor Canadian Shield. To reconcile the release of isotopically light carbon via kerogen oxidation with Earth surface carbon pool constraints, major oceanic degassing and biospheric regrowth must have acted in concert across glacial–interglacial transitions. Additionally, a process such as a strong shift in the ratio of C3 to C4-derived organic matter must be invoked to maintain isotope mass balance, a point key for reconciling the hypothesis with the carbon isotope record of marine dissolved inorganic carbon. In order to test this hypothesis, quantitative constraints on the contribution of kerogen oxidation to CO2 rise at glacial terminations are needed through systematic studies on (1) CO2 fluxes emanating from the weathering of different lithologies, (2) oxidation kinetics of kerogen ... |
format |
Article in Journal/Newspaper |
author |
Blattmann, Thomas |
spellingShingle |
Blattmann, Thomas Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle |
author_facet |
Blattmann, Thomas |
author_sort |
Blattmann, Thomas |
title |
Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle |
title_short |
Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle |
title_full |
Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle |
title_fullStr |
Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle |
title_full_unstemmed |
Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle |
title_sort |
ideas and perspectives: emerging contours of a dynamic exogenous kerogen cycle |
publisher |
Copernicus |
publishDate |
2022 |
url |
https://hdl.handle.net/20.500.11850/530887 https://doi.org/10.3929/ethz-b-000530887 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
glacier* Ice Sheet |
genre_facet |
glacier* Ice Sheet |
op_source |
Biogeosciences, 19 (2) |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-19-359-2022 info:eu-repo/semantics/altIdentifier/wos/000748748900001 http://hdl.handle.net/20.500.11850/530887 doi:10.3929/ethz-b-000530887 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/20.500.11850/530887 https://doi.org/10.3929/ethz-b-000530887 https://doi.org/10.5194/bg-19-359-2022 |
_version_ |
1766010462581817344 |