The Plenus Cold Event Record in the Abyssal DSDP Site 367 (Cape Verde, Central Atlantic): Environmental Perturbations and Impacts on the Nitrogen Cycle

The Oceanic Anoxic Event 2, at the Cenomanian-Turonian boundary (∼93.9 Ma), was an episode of widespread burial organic matter in marine sediments, underlined by a positive carbon-isotope (δ 13 C) excursion observed worldwide. Within this O 2 -depleted conditions, short interval cooling, termed as Plenus Cold Event, has been recorded many sites and sections northern hemisphere (Tethyan domain, Western Interior Seaway, proto-North Atlantic Ocean). But, its record impact on biogeochemical cycles carbon nitrogen southern part Central Ocean not explored yet. Here, we present detailed geochemical study Deep Sea Drilling Project site 367 (Cape Verde) based compilation previous new data isotope signals well trace element concentrations. aim is to better constrain evolution oxygenation water column associated changes cycle before during order understand paleoceanographic environmental consequences one deepest Ocean. Our dataset improves resolution δ C curve for site, propose chemo-stratigraphic frame allowing identification short-term negative Event. redox-sensitive proxies (Mo, U, V, Fe, Cu, Ni enrichments org /P total ) isotopic 15 N evidence that deep impacted cooling event. While anoxic conditions prevailed bottom waters onset characterized euxinic NH 4 + -rich column, event accompanied reoxygenation which had affected behavior elements caused cycling.