Geoscience Reference
In-Depth Information
Fig. 16.5 Seabed map of the nearshore zone of the Curonian Spit. Sedimentation environment:
1 - 3, lagoon: 1, mud accumulation; 2, wave sand accretion; 3, erosion; 4 -10 - marine: 4, wave and
current accretion; 5, wave accretion; 6, unstable accumulation and transit; 7, periodic alteration
of erosion/accretion processes; 8, transit; 9, weak erosion; 10, intense erosion; 11 - 15, lithological
types of sediments: 11, boulders, pebbles, gravel with sands; 12, pebbles, gravel with sands; 13,
sands; 14, silty clay mud; 15, outcrops of dense clay deposits, partly covered by sands
lengths of some troughs exceed 100 m, with an average width of about 4-5 m
(Fig. 16.5 ) . Generally, the processes on the coastal slope of this area are dominated
by longshore sediment transport. In the vicinity of Lesnoy and further to the north,
there are practically no sandy sediments on the bottom surface. Boulder-pebble
layer or extensive outcrops of greenish gray organic-rich laminated dense clays,
partly covered by sand, were mapped offshore at depths from 5 to 15 m. Hence, ero-
sion processes dominate within this area. Along the northern coast of the Sambian
Peninsula between the Cape Taran and 25-28 km of the Curonian Spit, the value of
sediment deficit is about 40 million m 3 (Boldyrev and Ryabkova 2001 ) .
Along the western coast of the Sambian Peninsula, sediment deficit is observed
between the capes Bakalinsky and Taran (Fig. 16.4 ) . The result of this effect is an
extremely high level of coastal retreat showing an annual volume of land loss by
landslides and erosion of about 70,000 m 3 (Boldyrev and Ryabkova 2001 ) .
16.4.2.3 Slope Slides
Landslides reach a very hazardous level in the Kaliningrad area. Huge landslides
took place along the 35-km active cliff coast of the Sambian Peninsula (Fig. 16.3 ) .
They cause the loss of hundreds of square meters of land annually. Since 2000, the
stability of the Kaliningrad coastal zone has deteriorated. In many areas, the plant
cover of the slopes has been destroyed and the slope steepness of potential landslide
areas has increased up to emergency levels. As a result, landslides have become
more frequent. Nowadays, there are some coastal areas where a risk of building
 
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