Abstract
A pronounced excursion in the carbon-isotope composition of
biospheric carbon and coeval seawater warming during the early Toarcian
(~183 Ma) has been linked to the large-scale transfer of 12C-enriched
carbon to the oceans and atmosphere. A European bias in the distribution
of available data means that the precise pattern, tempo and global
expression of this carbon cycle perturbation, and the associated
environmental responses, remain uncertain. Here, we present a new cmscale
terrestrial-dominated carbon-isotope record through an expanded
early Toarcian section from Japan that displays a negative excursion
pattern similar to marine and terrestrial carbon-isotope records
documented from Europe. These new data suggest that 12C-enriched carbon
was added to the biosphere in at least one rapid, millennial-scale pulse.
Sedimentological analysis indicates a close association between the
carbon-isotope excursion and high-energy sediment transport and enhanced
fluvial discharge. Together, these data support the hypothesis that a
sudden strengthening of the global hydrological cycle occurred in direct
and immediate response to rapid carbon release and atmospheric warming.
biospheric carbon and coeval seawater warming during the early Toarcian
(~183 Ma) has been linked to the large-scale transfer of 12C-enriched
carbon to the oceans and atmosphere. A European bias in the distribution
of available data means that the precise pattern, tempo and global
expression of this carbon cycle perturbation, and the associated
environmental responses, remain uncertain. Here, we present a new cmscale
terrestrial-dominated carbon-isotope record through an expanded
early Toarcian section from Japan that displays a negative excursion
pattern similar to marine and terrestrial carbon-isotope records
documented from Europe. These new data suggest that 12C-enriched carbon
was added to the biosphere in at least one rapid, millennial-scale pulse.
Sedimentological analysis indicates a close association between the
carbon-isotope excursion and high-energy sediment transport and enhanced
fluvial discharge. Together, these data support the hypothesis that a
sudden strengthening of the global hydrological cycle occurred in direct
and immediate response to rapid carbon release and atmospheric warming.
| Original language | English |
|---|---|
| Pages (from-to) | 162-170 |
| Number of pages | 9 |
| Journal | Earth and Planetary Science Letters |
| Volume | 481 |
| Early online date | 5 Nov 2017 |
| DOIs | |
| Publication status | Published - 1 Jan 2018 |
Bibliographical note
Part of this work was financially supported by JSPS KAKENHI 12J08818 and 15J08821 to KI. DBK acknowledges recipe of NERC Fellowship NE/I02089X/1 and grants from the Sasakawa Foundation of Great Britain, grant number 4883, and Daiwa Anglo-Japanese Foundation, grant number 10960/12369. This study contributes to IGCP 655. We thank M. Ikeda, T. Ohta, K. Suzuki, N. Nishida and K. Kawano for assistance in the field and/or helpful discussion. Fieldwork was carried out with full permission and support from its landowners. S. Nicoara and S. Kurokawa are thanked for analytical assistance. The comments of the Editor (D. Vance) and three reviewers (G. Suan, S. Bodin, and an anonymous reviewer) greatly improved the manuscript.Keywords
- Toarcian
- carbon isotope
- hydrological cycling
- sedimentology
- atmospheric warming
Access to Document
- Accepted Manuscript
© 2017. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/