Litodynamika podwodnego skłonu brzegowego na odcinku Mrzeżyno-Rowy
Abstract
THE LITHODYNAMIC OF SUBAQUEOUS SLOPE OF THE BĄLTIC SHORE IN THE MRZEŻYNO-ROWY SECTION
Summary
The paper presents results of studies on a 128 km section of subaqueous slope of shore, from Mrzeżyno and Rowy (Fig. 2). Echosoudings were made and samples of seafloor sediments taken from depths of 2, 5, and 10 m along sections normal to the shore and 2 km distant from one another. In the studied area, the subaqueous shore slope extends down to the depths of 7-10 m, ending as a rule at a marked break in seafloor profile (Fig. 1). On the basis of echograms and analyses of granulation and contents of heavy minerals in the 0.25-0.125 mm fraction, there were differentiated in the subaqueous shore slope area (Fig. 2):
1) seafloor areas with predominance of erosional processes, especially: a) areas completely devoid of modern sediments, b) areas with coarse-clastic residua! sediments, and c) areas of scoured medium- and coarse-grained sands.
2) seafloor areas with predominance of processes of redeposition and accumulation of sands, covered with well-sorted fine-grained sands.
An analysis of mobile means of content of the below 0.25 mm fraction (Fig. 4) showed that at the depth of 2 m the sediments are being redeposited from Dąbki eastwards and from Mielno westwards. The subaqueous shore slope section between Mielno and Dąbki represents a zone of divergence of net directions of transport of sediments.
Summary
The paper presents results of studies on a 128 km section of subaqueous slope of shore, from Mrzeżyno and Rowy (Fig. 2). Echosoudings were made and samples of seafloor sediments taken from depths of 2, 5, and 10 m along sections normal to the shore and 2 km distant from one another. In the studied area, the subaqueous shore slope extends down to the depths of 7-10 m, ending as a rule at a marked break in seafloor profile (Fig. 1). On the basis of echograms and analyses of granulation and contents of heavy minerals in the 0.25-0.125 mm fraction, there were differentiated in the subaqueous shore slope area (Fig. 2):
1) seafloor areas with predominance of erosional processes, especially: a) areas completely devoid of modern sediments, b) areas with coarse-clastic residua! sediments, and c) areas of scoured medium- and coarse-grained sands.
2) seafloor areas with predominance of processes of redeposition and accumulation of sands, covered with well-sorted fine-grained sands.
An analysis of mobile means of content of the below 0.25 mm fraction (Fig. 4) showed that at the depth of 2 m the sediments are being redeposited from Dąbki eastwards and from Mielno westwards. The subaqueous shore slope section between Mielno and Dąbki represents a zone of divergence of net directions of transport of sediments.