Geological and geomorphological structure of the Prut River valley in the Chernivtsi city area (according to engineering-geological exploration data)

Based on the engineering and geological surveys, the geological and geomorphological structure of the Quaternary-Pliocene deposits of the Prut River valley around the Chernivtsi area has been revealed. The morphometric parameters of the Prut River floodplain terraces have been characterized, with particular attention to the structural features of the sections of their accumulations. It has been found that the geological and geomorphological structure of this section of the Prut Valley is heterogeneous both due to the valley asymmetry and the presence of a transverse uplift in the form of the Tsetsyn and Khotyn Uplands, which at the intersection with the valley form the so-called Chernivtsi Gates. Outside the Gates, the asymmetry of the valley is manifested in the steeper right side of the valley and the more stepped left. Within the valley, its bottom is clearly distinguished, within which the high and low floodplains, as well as terraces 1 and 2, are located. The right bank of the valley is strongly affected by landslide processes, which are manifested mainly in the displacement of large blocks that involve the underlying clays. Therefore, terraces 7–10 are only fragmentarily traced here, and terraces 3 to 6 are not traced. Channel alluvium is absent in the sections of the middle and high terraces. The Pliocene 12th terrace is widely developed. Four paleovalleys of a diagonal north-western extension are cut into its surface, partially filled with lake-marsh deposits. In the southeastern part of the range, sections of the 11th terrace are available for study. On the valley's left bank, the terrace complex upstream and downstream of the Gate is more completely observed. However, here, they are also partially deformed by slope processes. Like on the right bank, the 12th terrace is widely spread. However, like on the right bank, its structure lacks channel alluvium. The presented stratigraphic division of the geological structure of most terraces is preliminary and requires further clarification using paleogeographic methods. Keywords: river terraces, floodplain, river valley, buried valleys, alluvium, geological sections, engineering geology, “Chernivtsi Gates”, geological and geomorphological structure.