Geoscience Reference
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that around 8,000 cal. BC the regression of the sea level slowed down and there may
even have been a small-scale transgression. In addition, in a very early phase of the
Littorina Sea, from 7,000-5,500 cal. BC, a previously unknown transgression phase
with an amplitude of ca. 2 m is assumed.
Compared with the Scandinavian rates of glacio-isostatic land uplift described
above, the developments on the eastern Baltic coast have to be considered as moder-
ate. At present, for example, the crustal movement of the area between the northern
part of Lithuania and north-eastern Estonia amounts to only +1 to 2 mm/year and is
thus barely able to offset the eustatic sea level rise of 1.8 mm/year (Rosentau et al.
2007
). However, during most of the Stone Age this part of the Baltic rim was rising
relatively so that, in principle, the shore-displacement models can also be used here
for the relative dating of archaeological sites that, today, are on dry land.
In Lithuania, it has been observed that the remains of Mesolithic and early
Neolithic settlements were located on river terraces and can be distinguished by
their different levels (Rimantiene
1994
). During the maximum of the Littorina
transgression during the seventh millennium BC, the low-lying terraces I and II
were flooded and habitation was only possible on the highest terraces, level III. At
that time, the level of the rivers did not rise as high as in the Pleistocene but had
reached a level of 5-6 m above the level I terraces. This observation regarding the
topography of these sites allows a subdivision of the Mesolithic period into three
Fig. 15.14
Ancient shorelines on the Kõpu peninsula of Hiiumaa island (Raukas and Ratas
1995
,
fig. 2)
