Branched GDGT and crenarchaeol lipids, and bulk parameters (TOC, TN, C/N, δ¹³C and d15N) of a 13.3 ka Kara Sea (St. Anna Trough; Arctic Ocean) core

Sediments (spanning a minimum of 13.3 ka) from the St. Anna Trough (Northern Kara Sea). The site has experienced extensive fluctuation in the delivery of river-derived organic matter (OM), caused by a eustatic change in sea level. This is in line with the record of the concentration of the isoprenoid GDGT, crenarchaeol, produced by marine Thaumarchaota, which was low at the bottom of the core, increasing gradually in the most shallow unit. The concentration of branched (br)GDGTs showed an opposite trend and a marked shift in distribution. The deepest sediments (>10 ka), with a distribution... Mehr ...