Diamond drilling as an aid in ore definition at the Dome Mine

CIM Bulletin, Vol. 75, No. 842, 1982

D.S. ROGERS, Chief Geologist, Dome Mines Limited South Porcupine, Ontario

Throughout the history of mining at the Dome, gold has been found in a number of different rock types and in association with a number of different structural settings. Diamond drilling plays an important role in the evaluation of the strati-graphic and structural features which control ore deposition. The main function of diamond drilling is to locate favourable areas of mineralization.To date, over 20,000 diamond drill holes have been drilled from combined surface and underground programs. Needless to say, a great many significant intersections, carrying a wide range of gold values, have resulted from the total of over 756 miles of drill cores which these programs have produced.However, the term "significant" takes on new meaning in light of the experience of diamond drilling in a number of ore-type situations at the Dome Mine. Drilling through individual ore veins, such as the Fuchsite Vein or the Quartz-Tourmaline Vein, often intersect the vein structure; however, assays from the veins frequently fail to yield any ore grades. Similarly, drill cores through stringer-type occurrences such as dacite or conglomerate, when assayed, fail to indicate the true size or grade of the orebody ultimately mined.

Mots Clés: Geology, Ore deposits Diamond drilling, Ore definition, Dome Mine, Gold deposits, Stratigraphy, Structure, Vein structure.