Geographia Polonica (1988) vol. 55

Full text

Preliminary stratigraphie studies on the Late Weichselian and Holocene development of the Hanó Bay, southeastern Sweden

Svante Bjôrck, Benneth Dennegârd

Geographia Polonica (1988) vol. 55, pp. 51-62

Abstract

Marine hydroacoustic and stratigraphic studies were carried out on Late Quaternary deposits in the Hand Bay, combined with sampling and 14 C datings of pine stumps and peat deposits, pollen analyses of peat and soil horizons and mapping of the sea-bottom by divers. It shows that major water-level changes of the Baltic have been the most important factor for understanding the occurrence and absence of deposits in the Hano Bay. The most spectacular phases in the history of the area is a "pine-phase" between c. 9700-9300 BP when forest spread to areas which today are situated c. 40 m below sea level and a "peat-phase" between c. 8800-7000 BP when peat accumulated rapidly inside the shore bank of that time in areas which today are situated between —7 and —14 m. These quite dramatic water-level changes caused extensive erosion and resedimentation which have resulted in a stratigraphy characterized by many and long hiatuses. No evidences for recent sedimentation of fine-grained sediments have been found in waters of less than c. 60 m water depth.

Keywords:

Svante Bjôrck, Department of Quaternary Geology. Lund University, Tornav, 13, S-223 63 Lund, Sweden
Benneth Dennegârd, Department of Marine Geology, Box 7064, S-402 32 Göteborg and Department of Geology, University of Göteborg and Chalmers University of Technology, S—412 96 Göteborg, Sweden