Stable carbon and oxygen isotope compositions of Eocene benthic foraminifera from ODP Site 207-1258


Autoria(s): Sexton, Philip F; Norris, Richard D; Wilson, Paul A; Pälike, Heiko; Westerhold, Thomas; Röhl, Ursula; Bolton, Clara T; Gibbs, Samantha J
Cobertura

LATITUDE: 9.433333 * LONGITUDE: -54.733050 * DATE/TIME START: 2003-01-22T00:00:00 * DATE/TIME END: 2003-02-01T00:00:00 * MINIMUM DEPTH, sediment/rock: 33.870 m * MAXIMUM DEPTH, sediment/rock: 58.135 m

Data(s)

14/07/2011

Resumo

'Hyperthermals' are intervals of rapid, pronounced global warming known from six episodes within the Palaeocene and Eocene epochs (~65-34 million years (Myr) ago) (Zachos et al., 2005, doi:10.1126/science.1109004; 2008, doi:10.1038/nature06588; Roehl et al., 2007, doi:10.1029/2007GC001784; Thomas et al., 2000; Cramer et al., 2003, doi:10.1029/2003PA000909; Lourens et al., 2005, doi:10.1038/nature03814; Petrizzo, 2005, doi:10.2973/odp.proc.sr.198.102.2005; Sexton et al., 2006, doi:10.1029/2005PA001253; Westerhold et al., 2007, doi:10.1029/2006PA001322; Edgar et al., 2007, doi:10.1038/nature06053; Nicolo et al., 2007, doi:10.1130/G23648A.1; Quillévéré et al., 2008, doi:10.1016/j.epsl.2007.10.040; Stap et al., 2010, doi:10.1130/G30777.1). The most extreme hyperthermal was the 170 thousand year (kyr) interval (Roehl et al., 2007) of 5-7 °C global warming (Zachos et al., 2008) during the Palaeocene-Eocene Thermal Maximum (PETM, 56 Myr ago). The PETM is widely attributed to massive release of greenhouse gases from buried sedimentary carbon reservoirs (Zachos et al., 2005; 2008; Lourenbs et al., 2005; Nicolo et al., 2007; Dickens et al., 1995, doi:10.1029/95PA02087; Dickens, 2000; 2003, doi:10.1016/S0012-821X(03)00325-X; Panchuk et al., 2008, doi:10.1130/G24474A.1) and other, comparatively modest, hyperthermals have also been linked to the release of sedimentary carbon (Zachos et al., 2008, Lourens et al., 2005; Nicolo et al., 2007; Dickens, 2003; Panchuk et al., 2003). Here we show, using new 2.4-Myr-long Eocene deep ocean records, that the comparatively modest hyperthermals are much more numerous than previously documented, paced by the eccentricity of Earth's orbit and have shorter durations (~40 kyr) and more rapid recovery phases than the PETM. These findings point to the operation of fundamentally different forcing and feedback mechanisms than for the PETM, involving redistribution of carbon among Earth's readily exchangeable surface reservoirs rather than carbon exhumation from, and subsequent burial back into, the sedimentary reservoir. Specifically, we interpret our records to indicate repeated, large-scale releases of dissolved organic carbon (at least 1,600 gigatonnes) from the ocean by ventilation (strengthened oxidation) of the ocean interior. The rapid recovery of the carbon cycle following each Eocene hyperthermal strongly suggests that carbon was resequestered by the ocean, rather than the much slower process of silicate rock weathering proposed for the PETM (Zachos et al., 2005; 2003). Our findings suggest that these pronounced climate warming events were driven not by repeated releases of carbon from buried sedimentary sources (Zachos et al., 2008, Lourens et al., 2005; Nicolo et al., 2007; Dickens, 2003; Panchuk et al., 2003) but, rather, by patterns of surficial carbon redistribution familiar from younger intervals of Earth history.

Formato

text/tab-separated-values, 2337 data points

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.763141

doi:10.1594/PANGAEA.763141

Idioma(s)

en

Publicador

PANGAEA

Relação

doi:10.1594/PANGAEA.763158

Sexton, Philip F; Norris, Richard D; Wilson, Paul A; Pälike, Heiko; Westerhold, Thomas; Röhl, Ursula; Bolton, Clara T; Gibbs, Samantha J (2011): Eocene global warming events driven by ventilation of oceanic dissolved organic carbon. Nature, 471, 349-352, doi:10.1038/nature09826

Westerhold, Thomas; Röhl, Ursula (2009): High resolution cyclostratigraphy of the early Eocene - new insights into the origin of the Cenozoic cooling trend. Climate of the Past, 5, 309-327, doi:10.5194/cp-5-309-2009

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Palavras-Chave #207-1258; AGE; Cibicidoides spp., d13C; Cibicidoides spp., d18O; COMPCORE; Composite Core; Depth, composite; Depth, composite revised; Depth, composite revised, adjusted; DEPTH, sediment/rock; Intercore correlation; Joides Resolution; Leg207; Mass spectrometer Europa Geo 20-20; North Atlantic Ocean; Ocean Drilling Program; ODP; ODP sample designation; Sample code/label
Tipo

Dataset