A generalized lithofacies model for glaciomarine and marine sequences in the Göteborg area, Sweden

Abstract

Strong stratigraphic trends can be recognized at many, if not most, of the valley localities below the marine limit in the Göteborg area. The deposits reflect the deglaciation and the isostatically induced regression following the last Weichselian glaciation. The generalized sequence of paleoenvironments and their associated deposits are used as an initial basis for comparing three stratigraphic examples from SW Sweden. These interpreted sections, in turn, are used to improve the paleogeographic model by specifying typical variations in important environmental parameters not originally included in the model. Ice-front proximity and meltwater drainage are decisively involved in the supply of sediments to both proximal and distal glaciomarine settings. Climatic variations further determine the extent of this supply and the balance between the contribution from the glacial source and the increasingly important supply from local erosion. Sedimentologic facies are described and discussed with respect to environmental interpretations in these late Quaternary, finegrained sequences. The lithofacies model reflects changes that are often time-transgressive between localities, but nevertheless comparable due to the similar depositional conditions. The resulting facies model can help in the observational, comparative and interpretive phases of an investigation.

Key Words:

• Göteborg
• Sweden
• stratigraphic model
• Weichselian deglaciation
• environmental evolution
• glaciomarine and marine
• fine-grained sediments
• sedimentation rates
• varves
• depositional processes
• iron sulfides
• textural features