气候变化领域集成服务门户(CCPortal): Unravelling the sources of carbon emissions at the onset of Oceanic Anoxic Event (OAE) 1a

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DOI	10.1016/j.epsl.2019.115947
	Unravelling the sources of carbon emissions at the onset of Oceanic Anoxic Event (OAE) 1a
	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.
发表日期	2020
ISSN	0012821X
卷号	530
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
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
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202466
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
推荐引用方式 GB/T 7714	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],2020,530.
APA	Adloff M..,Greene S.E..,Parkinson I.J..,Naafs B.D.A..,Preston W..,...&Monteiro F.M..(2020).Unravelling the sources of carbon emissions at the onset of Oceanic Anoxic Event (OAE) 1a.Earth and Planetary Science Letters,530.
MLA	Adloff M.,et al."Unravelling the sources of carbon emissions at the onset of Oceanic Anoxic Event (OAE) 1a".Earth and Planetary Science Letters 530(2020).