the mineral deposit (or portion of it), with the overlying and enclosing barren rock that is worked as one opencut mine. The opencut field is part of the mine’s land allotment, which also includes the barren rock removed from the mine and the work area and other production facilities. The upper contour of the field is the line where the sides of the mine intersect the ground surface, and the lower contour is the floor of the mine. The contouring of the opencut field consists in the establishment of the volumetric contour of the mine on geological maps and profiles; it includes the areas of the deposit that can be worked economically by the opencut method. In working horizontal and gently sloping veins, the dimensions of the open-cut field in the plan view are established based on the expedient rate of advance of the mining front, the allocation of the mining equipment, and the economy of the intramine shipments. The area of large opencut fields reaches 10–40 sq km, and the volume of the rock mass reaches 2–10 billion cu m.
IU. I. ANISTRATOV