DOI: 10.1016/j.gloplacha.2020.103126
论文题名: Unraveling short- and long-term carbon cycle variations during the Oceanic Anoxic Event 2 from the Paris Basin Chalk
作者: Boulila S. ; Charbonnier G. ; Spangenberg J.E. ; Gardin S. ; Galbrun B. ; Briard J. ; Le Callonnec L.
刊名: Global and Planetary Change
ISSN: 9218181
出版年: 2020
卷: 186 语种: 英语
英文关键词: Carbon cycle
; CTB
; Diachroneity
; Eccentricity amplification
; OAE2
; Paris Basin
; Volcanism
Scopus关键词: Core drilling
; Greenhouse gases
; Harmonic analysis
; Isotopes
; Limestone
; Stratigraphy
; Time series analysis
; Carbon cycles
; Diachroneity
; OAE2
; Paris Basin
; Volcanism
; Carbon
; amplification
; anoxic conditions
; carbon cycle
; carbon isotope
; cyclostratigraphy
; eccentricity
; global change
; long-term change
; paleoceanography
; paleoclimate
; paleoenvironment
; perturbation
; Phanerozoic
; stable isotope
; volcanism
; East Sussex
; Eastbourne
; England
; France
; Paris Basin
; United Kingdom
; Western Interior
英文摘要: The Oceanic Anoxic Event 2 (OAE2, ca. 94.6 Ma) is one of the major perturbations in the global carbon cycle during the Phanerozoic. Stable carbon isotopes (δ13C) from marine and continental sedimentary environments document this carbon cycle perturbation with a pronounced (> 2‰) positive carbon isotope excursion (CIE). Although the OAE2 stratigraphic interval has been intensively studied in terms of paleoceanography and paleoclimatology, several climatic and carbon cycle aspects are not yet well-understood. In particular, cyclic short-term Milankovitch-scale δ13C variations within the OAE2 and their potential implications for the global carbon cycle have been rarely addressed. Here, we present high-resolution (5 cm, ~2 kyr) δ13C data spanning the OAE2 from the Paris Basin Chalk (Poigny Craie-701 drill-core) to show high amplitude short-term δ13C oscillations, superimposed on the major CIE. Time-series analysis indicates that short-term oscillations are astronomically paced, with eccentricity cycles being the most prominent. Orbital forcing of δ13C variations is further supported by time-series analysis of the English Chalk (Eastbourne section). We suggest that orbitally paced carbon cycle oscillations were amplified by considerable emission of greenhouse gases from volcanism that caused the overall CIE. Astronomical calibration of the whole OAE2 (the perturbation and recovery phases) from the Poigny record provides a duration equivalent to eight to eight and a half short eccentricity cycles. Cyclostratigraphic correlations among several OAE2 key records indicate the same duration of the whole CIE. However, duration of the interval from the onset of CIE till the Cenomanian-Turonian boundary (CTB) is significantly different from one basin to another. In particular, a difference of almost two short eccentricity cycles is highlighted between the Anglo-Paris and Western Interior basins. According to cyclostratigraphic approach and correlations, the entry of W. devonense was at least 200 kyr later in the Western Interior Basin (WIB, USA) than in Europe. Key calcareous nannofossil biohorizons (e.g., Quadrum gartneri) are also stratigraphically upshifted in the WIB with respect to the European sections, hence concurring with the hypothesis of a younger CTB in the WIB. We ascribe such significant temporal offset to diachroneity of the CTB, which is likely the result of different, regional biotic responses to the global OAE2 paleoenvironmental perturbation. © 2020 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/158881
Appears in Collections: 气候变化与战略
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作者单位: Sorbonne Université, CNRS-INSU, Institut des Sciences de la Terre Paris, ISTEP UMR 7193, Paris, F-75005, France; ASD/IMCCE, CNRS-UMR 8028, Observatoire de Paris, PSL University, Sorbonne Université, 77 Avenue Denfert-Rochereau, Paris, 75014, France; Institute of Earth Sciences, University of Lausanne, Géopolis, Lausanne, CH-1015, Switzerland; Institute of Earth Surface Dynamics, University of Lausanne, Géopolis, Lausanne, CH-1015, Switzerland; Sorbonne Université, MNHN, CNRS, Centre de Recherche sur la Paléobiodiversité et les Paléoenvironnements, CR2P, Paris, F-75005, France
Recommended Citation:
Boulila S.,Charbonnier G.,Spangenberg J.E.,et al. Unraveling short- and long-term carbon cycle variations during the Oceanic Anoxic Event 2 from the Paris Basin Chalk[J]. Global and Planetary Change,2020-01-01,186