Palaeogeographic Model for the SW Estonian Coastal Zone of the Baltic Sea - The Baltic Sea Basin - page 180

Fig. 8.7 Palaeogeographic reconstruction of the Baltic Sea palaeocoastlines and water depths with
indication of water-level isobases (m a.s.l.) during its different stages: ( a ) the Baltic Ice Lake
during the deglaciation of the Pärnu area and formation of the end-moraines of the Pandivere-Neva
ice marginal zone at about 13,300 cal. years BP (Kalm 2006 ) , ( b ) the Baltic Ice Lake prior to the
Billingen drainage at about 11,700 cal. years BP, ( c ) the Baltic Ice Lake after the Billingen drainage
at about 11,600 cal. years BP, ( d ) Ancylus Lake at the beginning of the transgression and during
the Pulli settlements at about 10,500 cal. years BP, ( e ) Ancylus Lake during its maximum in the
Pärnu area at about 10,200 cal. years BP, ( f ) the Littorina Sea before the transgression and during
the Sindi-Lodja I and II settlements at about 9,000 cal. years BP, ( g ) alternative low water-level
(-5 m a.s.l. at Paikuse) scenario for the Littorina Sea before the transgression at about 9,000 cal.
years BP, ( h ) the Littorina Sea during its maximum in the Pärnu area at about 7,300 cal. years
BP, ( i ) the Littorina Sea after the transgression and during the Lemmetsa, Malda, Jõekalda and
Sindi-Lodja III settlements at about 6,000 cal. years BP
result of the slowdown in uplift (Fig. 8.5 ) . The only section with which we encoun-
tered minor difficulties to match actual shoreline tilting gradient to linear regression
was the long period from the Littorina Sea culmination to the present (Fig. 8.5 ) .
Because of the applied linear regression, it seems that our model slightly overes-
timates the shoreline tilting gradient for 6,000 cal. years BP. However, due to the
relatively small study area, this deviation is smaller than uncertainties from elevation
and dating, and we can use this approximation to interpolate the water-level surface
for this time slice. Baltic Ice Lake and Littorina Sea tilting gradients differ more
than threefold (Table 8.2 ) , which is also reflected in palaeocoastline positions, if
one compares the SE and NW parts of the maps (Fig. 8.7d , i). The results also show
that the direction of fastest uplift was migrated slightly westward during the Baltic
Ice Lake and then back north during the Holocene, ranging between 336 and 314 ◦ .