Stein, R et al. (2006): Bulk sedimentology from Sites M0002 and M0004 of the ACEX (Exp302) expedition to the Arctic Ocean. doi:10.1594/PANGAEA.476007, Supplement to:Stein, Ruediger; Boucsein, Bettina; Meyer, Hanno (2006): Anoxia and high primary production in the Paleogene central Arctic Ocean: first detailed records from Lomonosov Ridge. Geophysical Research Letters, 33, L18606, doi:10.1029/2006GL026776
Except for a few discontinuous fragments of the Late Cretaceous/Early Cenozoic climate history and depositional environment, the paleoenvironmental evolution of the pre-Neogene central Arctic Ocean was virtually unknown prior to the IODP Expedition 302 (Arctic Ocean Coring Expedition - ACEX) drilling campaign on Lomonosov Ridge in 2004. Here we present detailed organic carbon (OC) records from the entire ca. 200 m thick Paleogene OC-rich section of the ACEX drill sites. These records indicate euxinic "Black Sea-type" conditions favorable for the preservation of labile aquatic (marine algae-type) OC occur throughout the upper part of the early Eocene and the middle Eocene, explained by salinity stratification due to freshwater discharge. The superimposed short-term ("Milankovitch-type") variability in amount and composition of OC is related to changes in primary production and terrigenous input. Prominent early Eocene events of algae-type OC preservation coincide with global d13C events such as the PETM and Elmo events. The Elmo d13C Event has been identified in the Arctic Ocean for the first time.