The Ilnytsia Deposit

The geological structure consists of Miocene and Quaternary sediments. The coal-bearing sequence of the Ilnytsia Formation is composed of volcanogenic-sedimentary rocks containing five coal seams. The enclosing rocks are mainly clays, argillites, weakly cemented siltstones, tuffites, and locally polymictic sandstones. The total thickness of the coal-bearing succession reaches approximately 90 m. The deposit is situated within the Ilnytsia Syncline of the Chop Basin, where sedimentary rocks dip gently (up to 5°) toward the south and southwest. No major tectonic disturbances have been identified.

According to the Ukrainian Classification of Mineral Reserves, the Karierna and Kreminna areas belong to Group II in terms of geological complexity.

Hydrogeological conditions are considered relatively complex; however, they are suitable for open-pit mining. Mining and engineering-geological conditions are generally favorable for exploitation.

The mineral resource is represented by brown coal (lignite) occurring within the lower and upper coal-bearing horizons of the Pannonian Stage of the Ilnytsia Formation.

The coal is characterized by variable seam thickness and ash content. Ash content ranges from 9.7% to more than 40% in Seam I and from 8.4% to 38.1% in Seam II. The ash is powdery, non-caking, and consists predominantly of refractory Al₂O₃ and SiO₂ components. Ash fusion temperatures range from 1005–1240°C for Seam I and 1017–1263°C for Seam II. The coal is classified as medium-sulfur lignite, with pyritic sulfur being the dominant sulfur form. The semicoking tar yield on a dry ash-free basis varies from 1.06% to 1.95%, while the total tar yield ranges from 6.1% to 10.4%. According to DSTU 3472:2015, the coal is classified as Brown Coal (Grade B), Class 03, Category 0, Type 40, Subtype 10 (B.2B, 2BV).

Overall, the Ilnytsia Deposit represents a well-explored lignite deposit with sufficient geological information and favorable mining conditions for long-term industrial development.