Drill Targeting with 3-D Seismics for Volcanogenic Massive Sulfide Exploration in the Flin Flon Mining Camp

摘要

A 17-km(2) 3-D seismic survey was conducted in 2007 within the Flin Flon volcanogenic massive sulfide (VMS) mining camp as part of the Targeted Geoscience Initiative-3. The resultant 3-D images show strong reflectivity associated with the ore-hosting mine horizon and prominent reflections attributed to the known ore zones. Structural repetition of the mine horizon is clearly identified in the seismic images with at least three levels identified. The 3-D seismic images have been used in conjunction with detailed geologic and geophysical drill hole logs to identify new exploration drill targets. Results from the first three seismic-based exploration drill holes are presented. The drill holes encountered reflective geologic contacts at depths within 3 to 8% of those predicted from the 3-D seismic images. In the first case, a gabbro of no economic significance was encountered at the target depth. In the second case, a highly altered mafic volcanic panel with stringer mineralization was identified sitting blind beneath surface exposures of sandstone. In the third case, the target turned out to be an additional structural level of the mine rhyolite, which provides a new horizon for further exploration. A small massive sulfide ore lens was discovered during follow-up drilling around the third target. These results demonstrate that seismic methods can be successfully applied for mineral exploration in areas of existing infrastructure and cultural noise.