International Journal of Earth Sciences ( IF 2.278 ) Pub Date : 2021-02-22 , DOI: 10.1007/s00531-020-01972-z André Bornemann, Sofie Jehle, Friederike Lägel, Arne Deprez, Maria Rose Petrizzo, Robert P. Speijer
The Latest Danian Event (LDE, ~ 62.2 Ma) is characterized by global changes in the carbon cycle as indicated by two negative δ13C excursions of up to ~ 1‰. These δ13C shifts are accompanied by a 2–3 °C warming of both surface and deep waters based on benthic and planktic foraminiferal δ18O measurements, and the LDE has, thus, been considered as a so-called hyperthermal event. The event lasted for 200 kyr and has been identified in various ocean basins and shallow marine settings. Here, we present a compilation of data from three deep-sea cores covering the Pacific, North and South Atlantic oceans as well as a southern Tethyan shelf section to document the response of planktic foraminifera assemblages to ocean warming. In all studied successions, we observe the disappearance of the planktic foraminifer genus Praemurica on a global scale that took place close to the onset of the LDE. Moreover, on the long run, praemuricids were contemporaneously replaced by morozovellids. Both the decline of Praemurica and a temperature increase started between 200 and 260 kyr before the LDE onset and were punctuated by the LDE itself. In this paper, we propose two mechanisms that have controlled the environmental changes associated with this event, (1) increased activity of the North Atlantic Igneous Province acting on long time-scales, and (2) changes of orbital parameters resulting in insolation changes on shorter time-scales.
In contrast to a proposed muted benthic foraminiferal response, the planktic community has been substantially impacted by the LDE as indicated by changes in planktic foraminifera faunas and calcareous nannofossils. Finally, our quantitative and conventional approaches identifying stratigraphically important planktic foraminifera datum levels justify a revision of the upper Danian to lower Selandian planktic foraminifera biozonation.
最新大年事件（LDE，〜62.2马）的特征在于在碳循环全球变化由两个负δ表示13个向上的Ç游览〜1‰。这些δ 13 Ç位移基于伴随有2-3℃下加热表面和深水域的底栖和浮游有孔虫δ 18O测量，因此LDE被认为是所谓的高温事件。该活动历时200年，已在各种海盆和浅海环境中被发现。在这里，我们提供了来自太平洋，北大西洋和南大西洋以及南部特提斯陆架剖面的三个深海岩心的数据汇编，以记录浮游有孔虫组合对海洋变暖的响应。在所有研究的演替中，我们观察到浮游有孔虫属Praemurica在全球范围内的消失，发生在LDE发病初期。而且，从长远来看，早产儿同时被线虫代替。两者的衰老在LDE发生之前，温度开始升高200至260 kyr，并被LDE本身打断。在本文中，我们提出了两种机制来控制与此事件相关的环境变化：（1）长时尺度上北大西洋火成岩省活动的增加，以及（2）轨道参数的变化导致日照的变化较短的时间范围。