DOI: 10.1016/j.epsl.2019.115947
论文题名: Unravelling the sources of carbon emissions at the onset of Oceanic Anoxic Event (OAE) 1a
作者: Adloff M. ; Greene S.E. ; Parkinson I.J. ; Naafs B.D.A. ; Preston W. ; Ridgwell A. ; Lunt D.J. ; Castro Jiménez J.M. ; Monteiro F.M.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2020
卷: 530 语种: 英语
中文关键词: Aptian
; carbon source
; data assimilation
; osmium isotopes
; volcanism
英文关键词: Earth (planet)
; Isotopes
; Aptian
; Carbon source
; Data assimilation
; Osmium isotopes
; volcanism
; Organic carbon
; anoxic conditions
; Aptian
; carbon emission
; data assimilation
; emplacement
; large igneous province
; osmium isotope
; paleoceanography
; paleoclimate
; reconstruction
; volcanism
; Spain
英文摘要: The early Aptian Oceanic Anoxic Event (OAE) 1a represents a major perturbation of the Earth's climate system and in particular the carbon cycle, as evidenced by widespread preservation of organic matter in marine settings and a characteristic negative carbon isotopic excursion (CIE) at its onset, followed by a broad positive CIE. The contemporaneous emplacement of a large igneous province (LIP) is invoked as a trigger for OAE 1a (and OAEs in general), but this link and the ultimate source of the carbon perturbation at the onset of OAEs is still debated. In this study, we simultaneously assimilate an atmospheric pCO2 reconstruction along with a δ13C record from the Spanish Cau section in an Earth system model to obtain a novel transient reconstruction of emission rates and identify the primary carbon-emitting sources across the negative CIE interval at the onset of OAE 1a. We reconstruct carbon emissions of 4,300–29,200 Pg from a mixture of carbon sources. This estimate is a lower bound, as contemporaneous organic carbon burial is not accounted for. Carbon was first released at slow rates from a 13C-depleted reservoir (e.g. thermo- and/or biogenic methane from sill intrusions). Towards the end of the negative CIE the rate of emissions increased and they became more 13C-enriched, likely from a dominantly volcanic source (e.g. LIPs). New osmium isotope (187Os/188Os) measurements, from the same section as the pCO2 reconstruction and δ13C data, reveal a shift to less radiogenic values coinciding with the change towards mantle-derived carbon emissions as indicated by our modelling results, lending further support to our interpretation. These results highlight that geologically triggered carbon emissions were likely driving the OAE onset. © 2019 The Authors Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164844
Appears in Collections: 气候变化与战略
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作者单位: School of Geographical Sciences, University of Bristol, University RoadBS81SS, United Kingdom; School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, B152TT, United Kingdom; School of Earth Sciences, University of Bristol, Queen's RoadBS81RJ, United Kingdom; School of Chemistry, University of Bristol, Cantock's CloseBS81TS, United Kingdom; Department of Earth Sciences, University of California Riverside, 900 University Ave, Riverside, CA 92521, United States; Departamento de Geología, CEACTierra, Universidad de Jaén, Campus Las Lagunillas s/n, Jaén, 23071, Spain
Recommended Citation:
Adloff M.,Greene S.E.,Parkinson I.J.,et al. Unravelling the sources of carbon emissions at the onset of Oceanic Anoxic Event (OAE) 1a[J]. Earth and Planetary Science Letters,2020-01-01,530