Integrated geological and geophysical study of the Tagil river valley morphology in its middle course

Abstract

Relevance. Integrated geological and geophysical studies of a bridge in the Makhnevo village area are considered in the frame of the Urals eastern slope geology. Research objective is to study the lithology of the underlying part of the valley floor, determine soil physical and mechanical characteristics, and study a complex of fluvial terraces. Results. Relief elevations across the river valley have been studied, and four main fluvial terrace levels typical of the Urals eastern slope have been identified. An unstable section of the streambed with a canyonshaped valley above the neotectonic unwarping zone has been identified. The geological section of the river’s floodplain and streambed were studied based on geological and geophysical data. A change in the physical properties of glauconite sandstones and clays of Paleogene age in the recent underlying part of the river valley has been established. Layers of sand and glauconite sandstone that can be developed have been found at the new bridge site near the existing sand and gravel deposit. Conclusions. A complex of terraces of the Tagil river valley in its middle course is typical for the Urals eastern slope. The paleovalley is cut into a Paleogene glauconite sandstone layer. In the underlying part of the valley floor, changes in sandstones and clays physical properties have been recorded, and the presence of hypogene minerals was revealed. These are the signs of possible neotectonic processes in the series of the Cenozoic and Quaternary deposits.