Drowned Forests in the Gulf of Gdansk (Southern Baltic) as an Indicator of the Holocene Shoreline Changes - The Baltic Sea Basin - page 220

James 1847 , Fisher 1862 ) . In the Baltic Sea region, tree stumps rooted in the sea bed
were until recently known only from the coastal waters of Denmark and Germany
(e.g. Christensen 1995 , Lampe 2005 , Lampe et al. 2005 , Curry 2006 , Tauber 2007 ) .
In the southwestern part of the Baltic Sea, subboreal tree stumps occur not deeper
than 1 m below present sea level (Lampe 2005 ) . Much more common are underwater
sites of tree stumps from the Atlantic period drowned in German Baltic waters at
depths between 2 and 14 m below present sea level (Lampe et al. 2005 ) . The tree
stumps of pine ( Pinus ) in situ have also been identified offshore in Lithuanian waters
(Damusyte et al. 2004 , Damusyte 2006 ) . Conventional radiocarbon ages ( 14 C) for
these trees are 9,160 ± 60 and 6,930 ± 130 years BP and the water depths 27.0 and

14.5 m, respectively.
In Poland, numerous localities of tree stumps on beaches between Rowy and
Łeba have been known for many years (e.g. Tobolski et al. 1981 , Krapiec and Florek
2005 ) . The ages of the stumps examined there (oak, ash, alder and pine) ranged from
4,610 to 210 years BP. The first tree stumps found in situ in the Polish coastal zone
of the Baltic Sea were reported from Puck Lagoon. The wood of a stump excavated
from a depth of about 3 m was dated to 9,370 90 BP (Gd-7938) (unpublished

data). The peat deposits at the bottom of Puck Lagoon are of a similar age, hav-
ing been formed in the Preboreal and Boreal periods. Puck Lagoon itself is much
younger, existing since the end of the Atlantic period (e.g. Kramarska et al. 1995 ,
Uscinowicz and Miotk-Szpiganowicz 2003 ) . During field work carried out by the
Polish Geological Institute in 2006 in the Vistula Lagoon (Polish: Zalew Wislany ;
German: Frisches Haff ; Russian: Kaliningradskiy Zaliv ), tree stumps rooted in peat
have been recognized around the site with coordinates 54 ◦ 24.03 N and 19 ◦ 42.61 E
(some 5 km NE of Frombork). The alder stumps rooted in subboreal peat at a depth
of 2 m were dated to 4,770

±

± 35 BP (Poz-15115) and 3,295 ± 35 BP (Poz-1516)

(Ł˛czynski et al. 2007 ) .

11.2 Area, Scope and Methods of Study

TheGulfofGdansk is the southernmost part of the Gdansk Basin (southern Baltic
Sea). The external sea boundary of the Gulf of Gdansk is conventionally taken to be
a straight line connecting the promontories of Rozewie on the Polish coast and Taran
on the Sambian Peninsula (Russian exclave Kaliningrad). In the extreme western
part of the Gulf of Gdansk lies the Puck Bay, protected from the more open waters
by about 32-km-long Hel Peninsula. The southeastern part of the Gulf of Gdansk
is fringed by about 55-km-long Vistula Spit, which forms the Vistula Lagoon. The
area of the Gulf of Gdansk is about 5,000 km 2 . The maximum water depth is 107 m
in the northern part of the Gulf, in the Gdansk Deep.
The sea bed relief of the Gulf of Gdansk is very diverse. In depths of 0-10 m,
the near-shore slope is characterized by a system of bars. Outside the slope at a
distance of 20-25 km from the shore and to depths of 30-40 m, the sea bed relief
is flat or slightly hummocky with elevations of 0.5-5.3 m, locally up to 8 m with