Late Quaternary deglaciation in the Arctic Ocean: evidence from microfossils

Abstract

This thesis is the result of a three-year Ph.D investigation in the frame of three international research projects (1) OGS-EGLACOM (Evolution of a glacial Arctic continental margin: The Southern Svalbard ice stream-dominated sedimentary system), (2) PNRA-CORIBAR-IT (Ice dynamics and meltwater deposition in the NW Barents Sea: a 5-Nations effort for MeBo drilling the Arctic), and (3) Eurofleets2-PREPARED (Present and past flow regime on contourite drifts west of Spitsbergen). The overall goal of the Ph.D project was to advance knowledge about the distributions patterns of microfossils, with particular attention to calcareous nannofossils, as proxy of past climate changes in the Arctic Ocean, south and west of Svalbard. The micropaleontological approach used for palaeoclimate investigation is multi-proxy with the study of calcareous nannofossils compared with the results obtained from the analyses of other microfossil groups and sedimentological investigations, for a suited reconstruction of the late Quaternary palaeoenvironmental changes associated to climate. This research was conducted within a PNRA project (CORIBAR-IT) and a Eurofleets-2 project (PREPARED), both coordinated by the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS, Trieste) with the collaboration of several national and international universities and research institutes. The research group included: R. Melis (University of Trieste) working on benthic foraminifera; C. Morigi (University of Pisa and GEUS, Stratigraphy Department Geological Survey of Denmark and Greenland) and G. Varagona (University of Trieste) working on planktonic foraminifera; M. A. Bàrcena (University of Salamanca) and K. Mezgec (University of Trieste) working on diatoms; R.G. Lucchi (OGS, Trieste) coordinating the two projects and working on sediment facies, G. Giorgetti and M.E. Musco (University of Siena) working on clay minerals; A. Caburlotto (OGS, Trieste) working on multi-sensor core logger data; and M. Rebesco (OGS, Trieste) working on acoustic/seismic data, and coordination the OGS project EGLACOM. The involvement on this kind of studies included the participation at the oceanographic expedition PS99-1 onboard the R/V Polarstern (Bremerhaven-Longyearbyen, 13-23 June, 2016), during a Eurofleets-2 project coordinated by OGS, and the presentation of the results during several national and international workshops. In addition, in the context of the Ph.D education, two summer schools, the EIOC (Elements, isotopes and organic matter in chemostratigraphy) and the 12th USSP (Urbino Summer School in Paleoclimatology) were attended in 2014 and 2015.