Time scale of the Pliocene climatic cycles in the Arctic: Paleomagnetic Reconstruction

Lead Author Daria, Elkina
Institution Contact 1. All-Russian Research Institute for Geology and Mineral Resources of the World Ocean "VNIIOKEANGEOLOGIA", 1, Angliysky Avenue, St Petersburg, 190121, Russia 2. St Petersburg State University, Universitetskaya Embankment, 7-9, St Petersburg, 199034, Russia
Co-Authors Alexey Piskarev 1. All-Russian Research Institute for Geology and Mineral Resources of the World Ocean "VNIIOKEANGEOLOGIA", 1, Angliysky Avenue, St Petersburg, 190121, Russia 2. St Petersburg State University, Universitetskaya Embankment, 7-9, St Petersburg, 199034, Russia
Theme Theme 1: Vulnerability of Arctic Environments
Session Name 1.1 Climate Change and Environmental Management in the Arctic
Presentation Type Poster
Abstract text Considered to be an essential key for understanding of the Earth’s paleoclimate, the Arctic Ocean is currently an area of higher scientific interest. Despite the increasing number of studies, dating of marine sediments here is still a challenge due to the lack of biological material, restrictions of the radiocarbon method and discrepancies in the existing magnetostratigraphic patterns.
A paleomagnetic study that was carried out on 8 sedimentary cores recovered from the Mendeleev Rise has been revealed magnetostratigraphy up to the Pliocene. Moreover, these results have defined the mean sedimentation rate for the region, which does not exceed ca. 1.5 mm/ kyr. It means that contrary to the other widely accepted estimations establishing a cm/kyr rate for the whole Arctic Ocean, the sedimentation on the Mendeleev Rise can be characterized as rather low during the Quaternary period and first stage of Pliocene epoch.
Spikes of the natural remanent magnetization intensity and magnetic susceptibility have been discovered near almost all assigned chron boundaries that may act as an independent factor for their determination and also as a signature of some fluctuations in the regional depositional regimes or other significant events.
Furthermore, inversions and abrupt changes of the Earth’s magnetic field are nowadays thought to be linked with climatic variations to a greater extent than it was assumed earlier. Thus, the determined boundary of the geomagnetic polarity reversals could be correlated with some short-term climatic events in the Arctic Ocean.