The analysis the characteristics and specificity the formation of Predglintovoy lowlands is carried out. The regularities of changes in the state and the strength of blue clay at the depth of cut, taking into account their degree of disintegration – layering and fracturing. The influence of macro- and microcracks in the blue clay zone predglintovoy on their strength and deformation ability is investigated. Basic provisions of engineering-geological analysis of the territory are developed. Recommendations to improve the safety and reliability estimates of blue clay as base of constructions of different function are offered.