ОСОБЕННОСТИ ФОРМИРОВАНИЯ ОЗЁРНО-РУСЛОВЫХ СИСТЕМ СЕВЕРО-ЗАПАДА РОССИИ

The article discusses the issues of gradual changes in the pattern and other features of the river network that are still taking place in areas that have recently been freed from the Ostashkov glacial covers. The sections of the anomalous structure of the river network are identified, where the transformation of the network of flows of thawed glacial waters into a stable hydraulic network typical of riverbeds has not yet been completed. A longitudinal profile has not yet been developed on them, channel processes manifest themselves fragmentally, alternating with the accumulation of lake sediments or, conversely, with the erosion of the rock bed of streams and the formation of waterfalls. The very position of the riverbeds is unstable: they then split, then periodically connect. There are four such sections:

1) Lake Ladoga – Vuoksa River – Lake Saimaa (flow from Lake Ladoga to Lake Saimaa and further to the Baltic Sea);

2) Lake Ladoga – Neva River – Gulf of Finland (flow from Lake Ladoga through the newly formed Neva River to the Gulf of Finland of the Baltic Sea);

3) River Luga – the Rosson River – the Narva River (or vice versa);

4) the Onega River – branching with the Malaya Onega River – merging again with the Onega River.

The zoning of the territories freed from the last glacier was carried out according to various manifestations of anomalies in the structure of the river network: in the areas of glacial exaration, glacial accumulation and water-glacial accumulations, linking these anomalies also with the position of the receiving basins of rivers that existed at that time: the Baltic (Littoral) Sea, the White Sea, Ancyl Lake, Lake Saimaa.