DEGLACIATION IN EASTERN AND CENTRAL ... - arkisto.gsf.fi

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withdrew again from Salpausselkä I for at least 186 years before the Baltic Ice Lake
drained drained to the level of ofthe the Yoldia Yoldia Sea. The sharp change from fat clay to coarse silt
manifests manifests the dis discharge charge of the Baltic Ice Lake (BIll) (BIII) to the level of the Yoldia Sea
(YI).
The findings frndings presented here are imcompatible imcompatible with the varved varved clay chronology of
Sauramo Saura-o and Niemelä. Niemelä. The Ihalainen sequence shows shows that Salpausselkä I is
terminal, not not recessional, and that that there there is a gap of ofat at least 500 years in the varved
clay chronology chronologT of ofSouthern Southern Finland. Finland. The Lappeenranta Lappeenranta results results are, however, from
a different glaciallobe glacial lobe area that that those of of Sauramo and Niemelä. Niemelä.
If the bottom of the discharge öscharge varve varve was deposited 10 643 years before AD AD 1950
(Strömberg, 1990), 1990), the bottom-most layers layers of of the the fine-grained fine-grained sediments started to
deposit no later than 11 543 years before before AD 1950. According According to Sauramo's
chronology, chronology, the ice margin stopped at Salpausselkä salpausselkä I 660 years before the Baltic
Ice Ice Lake Lake (BIll) (BIII) dropped to the the Yoldia Yoldia (YI) level. Niemelä maintains that 1037 years
separated the the beginning beginning of the sedimentation sedimentation of Salpausselkä land I and the discharge of
the Baltic Ice Lake. If these figures frgures are are applied applied to Ihalainen, Ihalainen, the the Salpausselkä
readvance came to an an end and Salpausselkä I I started started to deposit at at 11 303-11 803-11 680
years before AD 1950. 1950. The turning turning point of the Heinola Heinola glaciation glaciation and the
Salpausselkä Salpausselkä readvance would would then then have been at at 11 LL 457-11 457-rL 834 884 years before AD
1950, 1950, and and the the fine-grained frne-grained sediments would would have started to deposit at Ihalainen at
11 LL 821-12 82L-L2 198 years before AD 1950. These These figures figures are minimum ones.
VI Rainio, H., Saarnisto, M. M. & Ekman, Ekman, I. I. 1995. Younger Dryas end
moraines moraines in Finland and NW NW Russia. Russia. In: In: IGCP IGCP 253 - Termination of
the Pleistocene Pleistocene - - final report. Lundqvist, J., Saarnisto, M. & & Rutter, N.
(eds.). Quaternary International, 28, 179-192.
(eds. ). Quaternary International, 28, L7 I -I92.
This paper is the frnal final report of project IGCP-253 on Finland, Russian Karelia and
Kola. Kola. It describes describes briefly the the location, structure and the relation to the highest sea
line of the Younger Dryas end moraines moraines in these areas. Problems related to the
correlation correlation of the ice-marginal ice-marginal moraines, including the Keiva moraines on the Kola
Peninsula, are discussed discussed and issues are defined that that require require further research. The
connection connection of the late-glacial late-glacial Baltic Sea to the White Sea and the drainage channels
of Lake Onega are discussed.
The The paper summarizes summarizes the the views views expressed by the authors in their earlier papers.
It is emphasized that the front of the continental ice sheet responded to climatic and
glaciological changes differently in different different parts parts of the ice sheet. This may partly
explain explain the age discrepancy between sectors ofchains of chains ofmorphologically of morphologically apparently
continuous continuous end moraines. moraines. In any any case the ice ice margin responded to climatic and
glaciological changes at somewhat different times in different sectors of the
Scandinavian Scandinavian ice sheet.