University of Oulu

Eskola, T., & Lunkka, J. P. (2022). Sediment sequence at muhos, western finland – a window to the pleistocene history of the scandinavian ice sheet. Boreas, 51(2), 332–349.

Sediment sequence at Muhos, western Finland : a window to the Pleistocene history of the Scandinavian Ice Sheet

Saved in:
Author: Eskola, Tiina1; Lunkka, Juha P.1
Organizations: 1Geology Research Group, Oulu Mining School, University of Oulu, P.O. Box 3000, Oulu, FI-90014 Finland
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 3.1 MB)
Persistent link:
Language: English
Published: John Wiley & Sons, 2022
Publish Date: 2022-11-02


In this study, we analysed a ~54-m sediment core consisting of Quaternary sediments overlying the Neoproterozoic Muhos Formation in central western Finland, adjacent to the Gulf of Bothnia. The sediments recovered were logged, and their sedimentological characteristics defined. Two fine-grained sediment units were subjected to biostratigraphical studies using pollen and diatom analyses. In addition, two sand-rich units and a wooden stick were dated by the optically stimulated luminescence (OSL) and 14C-AMS methods. The core sediments were divided into six units, where several diamicton, sand and gravel, and silt-and-clay-dominated beds were studied. The results indicate that the sediment succession of the core beneath the Holocene Litorina Sea and the Ancylus Lake sediments of the Baltic Basin were deposited in glacial and lacustrine environments that existed in the Oulu River valley during the time period between the Saalian glaciation (MIS 6) and the Holocene. The stratigraphical evidence, supported by the OSL ages, suggests that the Scandinavian Ice Sheet (SIS) entered the Muhos area during the Saalian glaciation, and at least during three separate time intervals in the Weichselian stage. Stratigraphically controlled and age-bracketed evidence shows that the first Weichselian SIS advance extended further south in the eastern part of Fennoscandia than previously estimated, and that this ice growth phase occurred during the Early Weichselian Herning Stadial (MIS 5d). The subsequent ice growth phases occurred during the Middle (MIS 4) and Late (MIS 2) Weichselian substages. The lacustrine and littoral sediments of the Muhos core were correlated with the late Eemian interglacial (MIS 5e) and two Weichselian interstadials (MIS 5c and MIS 3).

see all

Series: Boreas
ISSN: 0300-9483
ISSN-E: 1502-3885
ISSN-L: 0300-9483
Volume: 51
Issue: 2
Pages: 332 - 349
DOI: 10.1111/bor.12560
Type of Publication: A1 Journal article – refereed
Field of Science: 1171 Geosciences
Copyright information: © 2021 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.