UBC News

Common Drilling Mistakes in Gold Exploration and How to Avoid Them

Episode Summary

Rotary drilling's flexibility hides contamination risks that corrupt samples, while core drilling's precision costs triple but reveals exactly where million-dollar deposits hide. Percussion methods crack through granite rotary bits can't touch, and reverse circulation conserves precious desert water while maintaining sample purity. Learn more: https://www.element79.gold/

Episode Notes

Finding gold buried thousands of feet below the desert floor sounds simple until you realize one wrong drilling decision can cost your entire exploration budget. Mining teams drill hundreds of test holes every year, and most of them pick their drilling method based on what equipment the contractor already owns rather than what the actual rock formation needs. That single mistake turns profitable projects into expensive disasters that deliver contaminated samples and incomplete data. The difference between walking away with a worthless hole and discovering a deposit worth millions comes down to understanding how different drilling techniques perform in specific geological conditions. Every rock type demands its own approach, and trying to force one drilling method across different formations guarantees failure. Granite destroys drill bits designed for softer stone, while loose sand collapses into boreholes that lack proper support systems. Most exploration managers only discover these problems after burning through thousands of dollars on drilling that produces nothing useful. Rotary drilling remains the most flexible option because it adapts to nearly any rock type by switching between different bit designs as conditions change underground. The system spins a drill bit attached to connected pipes that extend deeper as the hole progresses through various rock layers. Drilling fluid pumps constantly down through those pipes, cooling the bit while carrying broken rock pieces back to the surface, where geologists can study them. This circulating fluid serves double duty by preventing loose or fractured rock from caving into the hole while keeping the drill bit from overheating during operation. The versatility makes rotary drilling perfect for early exploration when teams face uncertain geology and need equipment that handles unexpected formation changes without stopping work. However, the drilling mud that keeps everything running smoothly also introduces a significant downside by potentially mixing with rock samples and hiding subtle mineral indicators that matter tremendously for accurate resource estimates. Core drilling solves that contamination problem by extracting intact cylindrical samples that preserve the original rock structure and mineral distribution. The hollow tube bit cuts around the rock formation instead of grinding through it, leaving a solid cylinder inside that teams can pull up and examine in complete detail. Scientists slice these cores lengthwise to check mineral content, measure grades, and identify geological features that reveal whether deposits extend deeper into the ground or continue sideways along strike. Diamond-coated bits handle extremely hard crystalline rock that would quickly destroy conventional drill bits, though they cost significantly more and require careful handling. This method delivers the exact geological information needed for calculating resources, testing processing techniques, and deciding whether a mineral deposit justifies the massive expense of building an actual mine. The intact cores also provide material for laboratory analysis that determines the most efficient extraction methods. Reverse circulation drilling takes a completely different approach by pushing air down the outside of a double-walled pipe while rock chips travel up the inner tube straight to the surface without touching the borehole walls. This design prevents contamination from surrounding formations and delivers chips that accurately represent what exists at each specific depth without mixing between layers. The technique drills faster than traditional methods because high-pressure air breaks rock efficiently while clearing debris continuously without stopping to change drilling fluid or clean equipment. Desert exploration particularly benefits from reverse circulation drilling because it operates effectively with minimal water compared to conventional rotary systems that consume thousands of gallons per hole. Water scarcity in remote mining areas makes this efficiency crucial for keeping projects moving forward without expensive water transportation logistics. The dual-pipe system maintains consistently high sample quality by keeping rock chips isolated from hole walls and fluids that might introduce contamination. Percussion drilling breaks rock through repeated hammer impacts rather than grinding or cutting action, delivering strong blows that fracture hard, brittle formations where rotary methods struggle to achieve reasonable penetration rates. Down-hole hammers positioned directly behind the drill bit work especially well in fractured or extremely solid rock, where the pounding action efficiently breaks material without requiring extreme downward pressure that might damage expensive equipment. The method produces rock chips instead of intact cores, which limits detailed geological study but provides sufficient information for many early-stage exploration programs. Rock hardness dictates equipment requirements more than any other single factor, with soft sedimentary formations allowing faster drilling using less expensive equipment while hard igneous and metamorphic rocks demand tough bits featuring diamond or tungsten carbide cutting surfaces. Abrasive minerals within rock formations accelerate bit wear regardless of overall hardness, forcing frequent bit changes that add both time and cost to exploration budgets. Unstable ground creates additional challenges when loose materials cave into holes unless drilling methods include proper support through casing pipes or specialized fluids. Successful gold exploration matches drilling methods to specific rock conditions, sample requirements, and project budgets while accounting for logistical challenges in remote desert locations. Click on the link in the description to learn more about how experienced exploration teams combine geological knowledge with drilling technology expertise to design programs that maximize information value while controlling costs and avoiding the expensive mistakes that turn promising projects into financial disasters.

Element79 Gold Corp.
City: Vancouver
Address: 1100-1111 Melville St.
Website: https://www.element79.gold
Email: ms@element79.gold