| Abstract [eng] |
Temperature rise and global warming cause such problems as melting glaciers, rising sea levels, and the intensification and frequency of extreme weather events. Knowing accurate forecasts, it is possible to address and prepare various measures designed to help mitigate or adapt to its impact. One of the possible objects of these studies may be beach pebble and cobble deposits, which allow us to determine how the coast has been affected by various factors caused by climate change and thus predict how it may be affected in the future, and at the same time prevent possible climate change consequences. The goal of this work is to assess the dynamics of the seashore based on lithostastistic indicators of beach pebble and cobble deposits. The Curonian Spit seashore beach between the Russian-Lithuanian border and Juodkrantė was selected for the study. Pebble and cobble deposits were collected every one kilometer from an area of 5 square meters in the middle of the beach. In total, in 2023 20 samples were taken, and in 2024 - 23 samples. Each sample contained 100 randomly selected pebbles and cobbles. Based on the results of the study, it can be stated that the size of the rocks indicates that their place of formation was different, but they were brought to the sampling site by glaciers, strong storms or waves. Their high degree of sphericity showed that the samples had been in the water for a long time and were exposed to water erosion. When examining the greening, it can be seen that among the sediments studied in the work in 2023-2024, well-greened and greened rocks prevail, which suggests that the study area was exposed to intense waves. During the study, 38 different rock types were found in 2023. and 34 different rock types in 2024, but the dominant rocks in both years were granite, sandstone, basalt, quartz, quartzite, gneiss, rhyolite and lepidolite. The results obtained showed that the largest part of the rocks found in the Curonian Spit area are granite, sandstone and basalt types. The origin of the rocks determined that a significant part of the rocks found in the studied area were not formed here, but were brought by glaciers, storms, wind, waves or currents. Dynamic processes show that longitudinal transport dominates on the coast. Comparing the dynamic changes of the coast with sphericity, it was found that rounder grains are more often associated with positive changes of the coast. Hydrodynamic factors provide information about the seasonality of the waves of the Baltic Sea and determine the direction of wave approach to the coast, which determines the longitudinal transport of sediments on the studied coast. |
