To study the mineral composition of the planes, along which the core of argillites is destroyed in the process of drilling, samples of different degrees of stability were selected from the section of the Exploration Formation of well 1687 of the Talnakhskoye field.

The practice of exploratory drilling within the field indicates that the overwhelming number of complications and accidents during well sinking is associated with zones of argillized ignimbrites, genetically related to ore mineralization.