Environmental precursors to rapid light carbon injection at the Palaeocene/Eocene boundary

Abstract

The start of the Palaeocene/Eocene thermal maximum--a period of exceptional global warming about 55 million years ago--is marked by a prominent negative carbon isotope excursion that reflects a massive input of 13C-depleted ('light') carbon to the ocean-atmosphere system. It is often assumed that this carbon injection initiated the rapid increase in global surface temperatures and environmental change that characterize the climate perturbation, but the exact sequence of events remains uncertain. Here we present chemical and biotic records of environmental change across the Palaeocene/Eocene boundary from two sediment sections in New Jersey that have high sediment accumulation rates. We show that the onsets of environmental change (as recorded by the abundant occurrence ('acme') of the dinoflagellate cyst Apectodinium) and of surface-ocean warming (as evidenced by the palaeothermometer TEX86) preceded the light carbon injection by several thousand years. The onset of the Apectodinium acme also precedes the carbon isotope excursion in sections from the southwest Pacific Ocean and the North Sea, indicating that the early onset of environmental change was not confined to the New Jersey shelf. The lag of approximately 3,000 years between the onset of warming in New Jersey shelf waters and the carbon isotope excursion is consistent with the hypothesis that bottom water warming caused the injection of 13C-depleted carbon by triggering the dissociation of submarine methane hydrates, but the cause of the early warming remains uncertain.

Warming and environmental changes in the eastern North Sea Basin during the Palaeocene–Eocene Thermal Maximum as revealed by biomarker lipids

“…30 °C followed by a gradual decrease during the course of the PETM. These peak SST estimates are within the range of peak estimates obtained for the mid-latitude New Jersey shelf (Zachos et al, 2006;Sluijs et al, 2007b Zachos et al, 2003), or even a warming that preceded the negative CIE Tripati and Elderfield, 2004). However, both Danish sections exhibit a large decrease in SST of ca.…”

Climatic disaster at the Triassic-Jurassic boundary - a clay minerals and major elements record from the Polish Basin

“…This lat ter case sug gests that on set of warm ing (possi bly sub se quent to the vol ca nic CO 2 de gas sing) may slightly pre cede cat a strophic per tur ba tions of global car bon cy cle caused most prob a bly by meth ane hy drate dis so ci a tion (cf. Slujis et al, 2007;Hermoso et al, 2012;Brañski, 2012). The for mer seems to in di cate an other mech a nism of car bon cy cle dis tur bance, pos si bly thermogenic meth ane re lease dur ing the in tru sive phase of ig ne ous prov ince de vel op ment and im me diate warm ing.…”

Eustatic variations during the Paleocene‐Eocene greenhouse world

“…Still, the brief Chron C25n ($0.5 Ma; ) appears expanded relative to the very long and condensed interval between the onset of C24n and the CIE ($1.3 Ma) ( Figure 3). The CIE has been identified between 357.3 and $347 mbs from d 13 C records on multiple carbon bearing phases [Cramer et al, 1999;Sluijs et al, 2007b;John et al, 2008]. At Wilson Lake (Figure 4), the CIE has been identified between $110.0 and $96 mbs from d 13 C records on multiple carbon bearing phases Zachos et al, 2006;Sluijs et al, 2007b].…”

“…Symbols filled with stripes indicate marginal marine sites for which published information has indicated an increase in terrigenous sediment supply (TS) during the PETM or other hyperthermals. Increase in terrigenous sediment supply for Bass River and Wilson Lake is from Sluijs et al [2007b] and John et al [2008]. Numbers refer to the following sites: site 1, Lomonosov Ridge, Arctic Ocean (SL, TS ); site 2, Doel, North Sea (SL [Steurbaut et al, 2003]); site 3, Basque Region, Bay of Biscay (SL, TS Pujalte and Schmitz, 2006]); site 4, Forada, Central Northern Tethys (TS [Giusberti et al, 2007]); site 5, Turgay Straight (SL [Iakovleva et al, 2001]); site 6, Lodo Formation, California (SL [John et al, 2008]); site 7, Gebel Duwi, Central Southern Tethys (SL [Speijer and Morsi, 2002]); site 8, Tawanui, Southwestern Pacific (TS [Crouch et al, 2003b], SL [Crouch and Brinkhuis, 2005]); and site 9, Clarence River Valley, Southwestern Pacific (TS PETM [Hollis et al, 2005], TS other presumed hyperthermals [Nicolo et al, 2007]).…”

“…[12] The age models at Bass River and Wilson Lake are based on calcareous nannofossil biostratigraphy, and identification of the carbon isotope excursion (CIE) [Cramer et al, 1999;Sluijs et al, 2007b] (Figure 3). Additionally, paleomagnetic analyses have been carried out at Bass River [Cramer et al, 1999].…”