Prospects for using upper Pleistocene alluvial deposits from the South-East slope of the Central Russian Upland as raw materials for construction

Abstract

Introduction: At the moment, medium scale geological surveys determine the units to be mapped based on their stratigraphic features. Stratigraphic units include various lithological types of rocks whose consumer characteristics also vary.

Methodology: Using samples from the local databases compiled during geological surveys, we analysed the spatial variability of the lithological composition of Upper Eopleistocene alluvial deposits. In particular, we analysed the lithological composition of the upper Pleistocene alluvial deposits in river valleys. To classify the valleys, we used Horton's classification of rivers. The points of T1 and T2 sediment penetration were mapped on a 1:500000 scale base map and ranked by the type of river valley. For each point, the ratio of the thickness of clay deposits to the total thickness of the alluvial deposits was determined. The obtained ratios were grouped by the type of river valley. Histograms of their distribution were obtained with a step of 0.2.

Results and Discussion: In the valleys of the first type, the stripping ratio was 0.8‒1.0 for 55.4 % of penetrations, i.e. argillaceous rocks dominated. In the valleys of the IV and V types, the opposite dependence was observed –for 55.4 % of penetration points the stripping ratio was 0.0‒0.2. The share of penetration points with largely sand deposits (the stripping ratio from 0.0 to 0.4) was 64.9 %. The results of the study demonstrated that upper Pleistocene alluvial deposits in the river valleys of type I should be mapped separately, because they are practically useless with regard to sand deposits. The areas with the highest probability of moulding sands are deposits in the first and second fluvial terraces in the river valleys of the IV and V type.