Geology
From the geological point of view, the research area is located on recent deltaic sediments, which were derived mainly from the deposits of Nestos river. A characteristic of delta's sediments is the heterogeneity of materials. Various texture layers interlace each other to all directions. Also the presence of organic clay in several sites is characteristic, due to stagnant waters (marshes) of the delta. The lack of layers with coarse-grained materials (shingles, gravel) and the presence of thick layers of clay materials, reveal the weak activity of Nestos river in the Eastern compared to the Western region, and the origin of the region from flood processes. This has played also an important role in the absence of dynamic aquifers. The alterations of sand, clay and silt deposits, which results from a wide range of structural and depositional processes, produced a heterogeneous geological environment. These deposits are surrounded and combined in deeper layers with older sediments, originating from the hilly regions.
