An attempt to resolve the partly conflicting data and ideas on the ancylus-littorina transition

• Autorzy: Björck S. , Andrén T. , Bo Jensen J.
• Języki publikacji: EN

Abstrakty

EN

Lagoon gyttja layers occurring in anomalously high position (up to 2.5 m above the present-day sea level) The transition phase between the Ancylus and Littorina stages of the Baltic Sea is an old controversial topic. With the newest data available we try to reach a compromise between the "dramatic" model, including a sudden and large drainage of the Ancylus Lake, and the idea of a non-existing Ancylus drainage through Denmark. This new model includes a minor, perhaps 5 m, sudden erosion and forced regression slightly before 10,000 cal. yrs BP. This was followed by a 200–300 yr long period when the outlet through Denmark and Great Belt (Dana River) was characterized by a variable fluvial environment creating fluvial, levée and lacustrine deposits. During this period of rapidly rising sea level, we postulate that the gradient between the Ancylus Lake and sea level gradually decreased from some 5 m until sea level had reached the Ancylus and Darss Sill level. After this point in time occasional pulses of marine water could easier enter into the Baltic basin, which is seen as brackish pulses as early as 9800 cal. yrs BP in records from the Bornholm and Gotland basins, but also from Blekinge. It would, however, take another c. 1500 years before the Öresund threshold was flooded by the rising sea level, causing a significant rise in salinity sometime between 8500–8000 cal. yrs BP, and marking the true onset of the Littorina Sea.

Słowa kluczowe

EN

sea level; Ancylus Lake; Littorina Sea; Baltic Sea

• Wydawca: Państwowy Instytut Geologiczny - Państwowy Instytut Badawczy
• Czasopismo: Polish Geological Institute Special Papers
• Rocznik: 2008
• Tom: Vol. 23
• Strony: 21--26
• Opis fizyczny: bibliogr. 20 poz., rys.

Twórcy

autor

Björck S.

autor

Andrén T.

autor

Bo Jensen J.

• GeoBiosphere Science Centre, Dept. of Geology, Quaternary Sciences, Lund University, Sölveg. 12, SE-223 62 Lund, Sweden,

Bibliografia

• ANDRÉN E., ANDRÉN T., SOHLENIUS G., 2000a - The Holocene history of the southwestern Baltic Sea as reflected in a sediment core from the Bornholm Basin. Boreas, 29: 233-250.
• ANDRÉN E., ANDRÉN T., KUNZENDORF H., 2000b - Holocene history of the Baltic Sea as a background for assessing records of human impact in the sediments of the Gotland Basin. The Holocene, 10: 687-702.
• BENNIKE O., JENSEN J.B., LEMKE W., 1998 - Fauna and flora in submarine early Holocene lake-marl deposits from the south-western Baltic Sea. The Holocene, 8: 353-358.
• BENNIKE O., JENSEN J. B., KONRADI P. B., LEMKE W., HEINEMEIER J., 2000 - Early Holocene drowned lagoonal deposits from the Kattegatt, southern Scandinavia. Boreas, 29: 272-286.
• BENNIKE O., JENSEN J.B., LEMKE W., KUIJPERS A., LOMHOLT S., 2004 -Late- and postglacial history of the Great Belt, Denmark. Boreas, 33: 18-33.
• BERGLUND B.E., SANDGREN P., BARNEKOW L., HANNON G., JIANG H., SKOG G., YU S., 2005 - Early Holocene history of the Baltic Sea, as reflected in coastal sediments in Blekinge, southeastern Sweden. Quater. Internat., 130: 111-139.
• BJÖRCK S., 1987 - The answer to the Ancylus enigma? - Presentation of a working hypothesis. GFF, 109: 171-176.
• BJÖRCK, S. 1995 - A review of the history of the Baltic Sea, 13.0-8.0 ka BP. Quater. Internat., 27: 19-40.
• BJÖRCK S., DENNEGÅRD B., 1988 - Preliminary stratigraphic studies on the Late Weichselian and Holocene development of the Hanö Bay, southeastern Sweden. Geogr. Pol., 55: 51-62.
• BJÖRCK S., MUSCHELER R., KROMER B., ANDRESEN C.S., HEINEMEIER J., JOHNSEN S.J., CONLEY D., KOÇ N., SPURK M., VESKI S., 2001 - High-resolution analyses of an early Holocene climate event may imply decreased solar forcing as an important climate trigger. Geology, 29, 12: 1107-1110.
• CLARK J.A., FARRELL W.E., PELTIER W.R., 1978 - Global changes in postglacial sea level: a numerical calculation. Quater. Res., 9: 265-287.
• JENSEN J.B., BENNIKE O., WITKOWSKI A., LEMKE W., KUIJPERS A., 1999 - Early Holocene history of the south- western Baltic Sea: the Ancylus Lake stage. Boreas, 28: 437-453.
• JENSEN J. B., KUIJPERS A., BENNIKE O., LEMKE W., 2002 - Balkat, the Baltic Sea without frontiers. Geologi, nyt fra GEUS, 4.
• LAMBECK K., CHAPPELL J., 2001 - Sea level change through the last glacial cycle. Science, 292: 679-686.
• LEMKE W., JENSEN J.B., BENNIKE O., WITKOWSKI A., KUIJPERS A., 1999 - No indication of a deeply incised Dana River between Arkona Basin and Mecklenburg Bay. Baltica, 12: 66-70.
• NOVAK B., BJÖRCK S., 1998 - Marine seismic studies in southern Kattegatt, with special emphasis on longitudinal bars and their possible relationship to the drainage of the Ancylus Lake. GFF, 120: 293-302.
• POST von L., 1929 - Svea. Göta och Dana älvar. Ymer, 49: 1-33.
• REIMER P.J., BAILLIE M.G.L., BARD E., BAYLISS A., BECK J.W., BERTRAND C.J.H., BLACKWELL P.G., BUCK C.E., BURR G.S., CUTLER K.B., DAMON P.E., EDWARDS R.L., FAIRBANKS R.G., FRIEDRICH M., GUILDERSON T.P., HOGG A.G., HUGHEN K.A., KROMER B., MCCORMAC F.G., MANNING S., BRONK RAMSEY C., REIMER R.W, REMMELE S., SOUTHOPN J.R., STUIVER M., TALAMO S., TAYLOR F.W., VAN DER PLICHT J., WEYHENNMEYER C.E., 2004 - IntCal04 terrestrial radiocarbon age calibration, 0-26 cal kyr BP. Radiocarbon, 46: 1029-1058.
• SOHLENIUS G., STERNBECK J., ANDRÉN E., WESTMAN P., 1996 - Holocene history of the Baltic Sea as recorded in a sediment core from the Gotland Deep. Marine Geol., 134: 183-201.
• WITKOWSKI A., BROSZINSKI A., BENNIKE O., JANCZAK-KOSTECKA B., JENSEN J.B., LEMKE W., ENDLER R., KUIJPERS A., 2005 - Darss Sill as a biological border in the fossil record of the Baltic Sea: evidence from diatoms. Quater. Internat., 130: 97-109.