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Table 12.1 Volume of selected coastal barriers and corresponding retreat of feeder cliffs at the
southern Baltic coast (Barthel 2002 , Hoffmann 2004 , Naumann 2006 ) during the last 8,000 years.
For barrier and cliff locations, see Fig. 12.1
Coastal barrier (no.
in Fig. 12.1 )
Estimated volume
(mill m 3 )
Mean length/height
of feeding cliffs (m)
Calculated cliff
retreat (m)
Kieler Ort (2)
11
4,000/4
690
Zingst (6)
450
No cliff
?
Hiddensee (7)
270
4,500/40
1,500
Bug (8)
66
8,000/8
1,030
Schaabe (9)
103
17,300/35
170
Peenemünde (13)
420
10,500/30
1,810
Pudagla (14)
150
above-mentioned volumes correspond to a mean cliff retreat during the last 8,000
years as listed in Table 12.1 . Similar estimations were published by Uscinowicz
( 2003 , 2006 ) , who assumes that the Polish coast has receded 1,000-1,500 m.
Except for the Zingst study area, all barriers can be explained to be built up
mainly from eroded sediment from the nearby cliff sections. For the Zingst penin-
sula, the provenance of the sandy material is more difficult to explain; an obvious
feeder cliff does not exist today. The offshore area is widely covered by silty sed-
iment of glacio-lacustrine origin (Fig. 12.1 ) which cannot provide barrier building
sand. The only possible sources are hypothetical glacio-lacustrine/fluvial sand bod-
ies scattered offshore in the vicinity of today's peninsula. Analogue sediment bodies
were found at the base of the coastal barriers building the backbone of the recent
peninsula (Fig. 12.6 ) . These sediments probably built the glacial lake shore and
fringing small deltas and were fluvially intersected after the lake level fell. The
form and extent of these sediment bodies cannot be reconstructed because they are
now completely eroded. The eroded material built spits which became permanently
reshaped and transgressed with the rising sea level to the recent position of the
peninsula. Behind the slowly moving spits, slack water areas occurred temporarily.
Here, small-sized thin lagoonal mud layers accumulated which are located today
some hundred to thousand meters offshore of Zingst and Hiddensee and are the
only remaining traces of the transgressive proto-barriers.
12.5 Discussion and Conclusions
The internal structure of the barriers shows some critical aspects. The lagoonal mud
underlying the barrier sand was deposited under calm and sheltered conditions, pro-
vided by seaward islands, spits or barriers. Further, the occurrence of mud implies
a barrier transgression over the lagoonal sediments and to the limited extent of the
barrier shift (Hurtig 1954 , Kliewe and Janke 1982 , Lampe 2005 ) . As evident from
ship-based offshore investigations (vibrocoring and SES surveys), non-compacted
Late Glacial and Early Holocene lake and peat deposits exist seawards of the present
 
 
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