Provenance analysis of Late Pleistocene Arctic glacial marine and lacustrine sediments:implications for deglaciation dynamics

• Main Author: Alatarvas, R. (Raisa)
• Other Authors: Strand, K. (Kari), Lunkka, J. (Juha Pekka)
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Oulun yliopisto 2023
• Subjects: Arctic; Arctic Ocean; Baltic Ice Lake; Baltic Sea; De Long Trough; East Siberian Sea; Landsort Deep; Lomonosov Ridge; clay mineralogy; deglaciation; facies analysis; heavy minerals; ice sheet; isotope; Arktis; Baltian jääjärvi; De Long kanavansuuviuhka; Itä-Siperian meri; Itämeri; Jäämeri; Landsortin syvänne; Lomonosovin harjanne; deglasiaatio; fasiesanalyysi; isotoopit; jäätiköt; raskasmineraalit; savimineralogia; East Siberian Shelf; Arktis*; Fennoscandian; Ice Sheet; SWERUS-C3
• Online Access: http://urn.fi/urn:isbn:9789526237442

Abstract In this PhD thesis glacial sediment from the East Siberian Sea/Shelf, central Arctic Ocean, and Baltic Sea were investigated in order to present interactions between the Late Pleistocene deglaciations and sediment deposition in marine and lacustrine environments in the Northern Hemisphere. The main objective of the study was to determine provenance areas and transport mechanisms and pathways for sediments from the De Long Trough, southern and central Lomonosov Ridge, and Landsort Deep. Sedimentological, mineralogical, and geochemical proxies were determined from the SWERUS-C3, IODP Expedition 347 Site M0063, and AO96/12-1pc core materials to establish the rate of processes and products related to deglaciation dynamics, such as loss of ice and meltwater release. The heavy mineral signature of marine glacial sediments from a glacial trough and the related trough mouth fan setting from the East Siberian Shelf were used for far field reconstructions of ice sheet activity on the East Siberian continental margin. The changes in the mineralogy between the diamicts and the overlying clay-rich sediments from the last glacial cycle deposited in the De Long Trough reflect the changes related to deglaciation in the East Siberian continental margin. The clay mineral content and the isotope signatures of the sediments from the Lomonosov Ridge, central Arctic Ocean were used to evaluate the provenances and transportation of the detrital sediments related to the deglaciation event during the transition from Marine Isotope Stage (MIS) 4 to 3. Sedimentological, mineralogical, and geochemical analyses of the sediments from the Landsort Deep enabled to establish more detailed interpretation of the depositional events and environments of the sediments related to the Baltic Ice Lake between ~13.5 and 10.5 ka BP. The sediments reflect the fluctuations of the Fennoscandian Ice Sheet; retreat and melting of the ice sheet and/or lake drainage events associated to warm periods, such as the Bølling/Allerød interstadial; and the ...