Magnitude and profile of organic carbon isotope records from the Paleocene-Eocene Thermal Maximum: Evidence from northern Spain

作者：Manners Hayley R^*; Grimes Stephen T; Sutton Paul A; Domingo Laura; Leng Melanie J; Twitchett Richard J; Hart Malcolm B; Dunkley Jones Tom; Pancost Richard D; Duller Robert; Lopez Martinez Nieves

来源：Earth and Planetary Science Letters, 2013, 376: 220-230.

DOI：10.1016/j.epsl.2013.06.016

• carbon isotopes
• Paleocene-Eocene thermal maximum
• CIE
• Northern Spain

The Paleocene-Eocene Thermal Maximum (PETM), a hyperthermal event that occurred ca. 56 Ma, has been attributed to the release of substantial amounts of carbon, affecting the atmosphere, biosphere and the oceans. Current issues with respect to our understanding of the PETM include the amount of carbon released, the duration of carbon release, and the mechanism(s) of release, all of which are related to the magnitude and profile of the associated Carbon Isotope Excursion (CIE). High-resolution organic carbon profiles (delta C-13) of six PETM sections in northern Spain are presented that span a transect from continental to marine environments. These data represent the highest-resolution isotope records for these sections and allow a comparison of the magnitude of the excursion, the shape of the vertical delta C-13 profile during the PETM episode, and the relative timing of the onset of the excursion across a linked sediment routing system. Previous studies using carbonate delta C-13 data have suggested that the continental Claret Conglomerate, found in this region, formed synchronously with a marine clay-rich siliciclastic unit, with these key lithological changes interpreted to be driven by increased seasonal rainfall-runoff in the warmer PETM climate. Our data suggest that deposition of these units did not immediately follow the CIE onset, indicating that there may be a temporal lag between the onset of the PETM warming and the response of the depositional systems in northern Spain. No systematic variation in the magnitude of the CIE between different depositional environments was found; the marine CIE magnitudes are at the higher end of those previously described (3.7 +/- 1.4 parts per thousand), and the continental ranges are lower (3.1 +/- 1.3 parts per thousand).

• 出版日期2013-8-15