METHOD FOR PROSPECT HOLE DRILLING IN PERMAFROST ZONE

摘要

FIELD: geology, particularly to drill prospect holes in permafrost zones during placer deposit exploration. ^ SUBSTANCE: method involves drilling prospect hole having different cross-sections in overburden and productive seam. Prospect hole cross-section is selected from mathematical expression, which minimizes overburden footage. ^ EFFECT: increased drilling speed without decrease of mineral sample volume to be taken from productive seam.