Mining of thin coal seams using surface-underground methods

Shallow hard coal deposits in the form of seams can be mined using surface-underground methods. These methods are characterized by the exploitation of the deposit from the surface, while the mining process itself takes place underground. The large variability of the mining and geological conditions was the reason for the emergence of many mining methods and systems as well as machines, sometimes used only locally in various parts of the world. The article presents the surface-underground methods used around the world. Attention is paid to unusual and rarely used methods and machines, which are not utilized in Polandfor various reasons. The present article discusses mining machines used in the methods of Highwall, Auger, and Punch longwall mining along with their types and varieties.