Engineering-geological conditions of the Shirvan Steppe of the Kura-Aras Lowland of Azerbaijan Republic and the influence of the Upper-Shirvan Canal on it

Abstract

Since 1950, the area of the Shirvan Steppe has been subject to numerous ameliora- tive measures, as well as the construction of a number of hydrotechnical facilities. Natural and anthropogenic effects have altered the level of groundwater, mineralization level, chemical composition, engineering-geological conditions, soil salinity, and chemical composition of soils. In order to reflect the engineering-geological conditions of the Shirvan Steppe, geological-hydrochemical sections were created in two directions, in the direction of groundwater flow (I-I) and the direction across the flow of groundwater (II-II). The analysis consid- ered the engineering-geological, physical-geographical, geomorphological, geological, and other conditions of the studied area before and after construction of the Upper Shirvan Canal. Along the route of the Upper Shirvan Canal, the research revealed the main soils as follows: loam, clay, gravel-pebble, sand, and loamy sand. The engineering-geological parameters such as minimum moisture capacity, hygroscopic moisture, volume, weight, density, porosity, and granulometric composition of the soils along the route of Ujar, Kurdamir, Goychay regions, and the Upper Shirvan Canal have been determined. Over the 70-year continuous operation of the Upper Shirvan Canal, settlements in the area of its influence expanded, thereby increasing the loading on the canal beyond the norm. As a result of damage to the concrete coatings of the canal, the quality of operation has decreased, some infrastructure located on it has ceased to function, and water losses from the canal have increased. In such conditions, it is important to study the formation of engineering-geological conditions resulting from natural and anthropogenic effects and to take preventive measures against negative impacts. During the reconstruction and subsequent operation of the canal to provide water to the newly irrigated land areas in the Shirvan Steppe, there should be taken into account the technogenic effects on the geological environment and relevant proposals of important scientific and practical importance regarding the reconstruction project.