From Uncertainty to Discovery: Structural Quality Optimization in Action

Imagine this: you drill your very first borehole into a promising geophysical and copper soil anomaly - and strike significant mineralization right away. Excitement soars: it feels like you’re onto a major discovery. Then, just as quickly, frustration sets in. Your follow-up holes miss the mark, failing to intersect the target. No oriented core, no structural insight - just guesswork disguised as drilling. We call this the Second Borehole Problem (Vektore (2012–2025) - when we think we’re chasing geometry and continuity, but you’re flying blind. No real structural framework, no factual geometrical controls - hoping for the best. Sound familiar.

?Please note that, by Vektore’s Data Anonymization (DA) protocols, certain details about the deposit have been withheld or generalised to protect our clients.

Our mission was clear: revisit the discovery hole and extract structural insights - both those tied to mineralization and those defining the broader architecture. The challenge? Working with non-oriented core while still delivering a reliable structural framework to guide follow-up drilling. We took it head-on. This is where Orebody Knowledge (OBK) plays a critical role (Maptek, 2018). A robust OBK framework ensures that early-stage structural insights are captured, reducing uncertainty and increasing the efficiency of subsequent drilling decisions. Without it, every hole risks being just another guess.

Our approach leveraged Structural Inversion?, which together with Structural Convergence? comprises the concept of Structural Quality Optimization? (QO) proposed by Monteiro (2005) and Vektore (2012–2025). We set a reference mark on the mineralized core and collected structural data using the Structural Vectoring? Log (SVL – Vektore, 2012). To strengthen our dataset, we worked with the client to open a trench along the dip direction of the discovery hole - an essential step in validating our reconstructed architecture (see Figure 2).

Structural Inversion? is a cutting-edge method that reconstructs the likely orientations of key mineralization-related structures, using a robust algebraic algorithm in 3D (see Figure 3). By directly harmonizing the inversion set with a reference dataset obtained from within the same structural domain, it reveals geometrical relationships that would otherwise remain hidden. This powerful approach unlocks new structural insights, giving geologists a clearer picture of the mineralization architecture early on. With this knowledge, drilling strategies can be redefined with precision - maximizing efficiency and reducing costly guesswork.

Based on our Structural Inversion? study, we provided a clear prescription for optimized drilling: the next borehole should be drilled from W-WNW to E-ESE to properly intersect the mineralization projected from the discovery hole. To ensure precise execution, we supplied the client with a recommended drill site (N-E-Elevation coordinates) and the exact dip/dip-direction for the verification (proposed) hole: 50°/115° (see Figure 4). This approach is designed to maximize mineralization intersection, reducing uncertainty and improving targeting efficiency.

Initially, the client explored alternative drilling strategies, opting to test continuity through a series of additional boreholes rather than immediately following the prescribed validation hole. While this approach provided valuable data, the sought-after mineralization was ultimately intersected only after implementing the Structural Inversion?-based recommendations (see Figure 5). In hindsight, had the prescribed approach been followed earlier, the discovery could have been made more efficiently, with fewer drill holes and lower costs. A post-campaign assessment determined that the follow up non-intersecting holes accounted for approximately 45% of the drilling budget allocated to this target - highlighting the potential for significant resource optimization in future exploration programs.

This highlights the Value of Information (VoI) in mineral exploration (Lawie, 2024). Spending early on high-confidence structural data - such as that derived from Structural Inversion? - reduces wasted drilling and maximizes the return on every meter drilled. In the end, the cost of not having the right information far outweighs the investment in obtaining it.

This case highlights a fundamental challenge in exploration: drilling without a clear structural framework leads to unnecessary cost and uncertainty. The Second Borehole Problem is real—without proper orientation, even promising discoveries can become difficult to follow up. By applying Structural Inversion? on non-oriented core, we reconstructed the mineralization architecture, providing a data-driven drilling prescription that ultimately led to success. However, the delay in adopting this approach resulted in significant resource losses, with non-intersecting holes consuming 45% of the drilling budget. The key takeaways are:

·??????? Orebody Knowledge (OBK) is critical. Without a solid understanding of structural controls, every drill hole is a high risk.

·??????? The right information at the right time saves resources. The Value of Information (VoI) in structural analysis is undeniable - early investment in high-confidence data prevents wasted drilling.

·??????? Precision and smart drilling is the future. Methods like Structural Inversion?, Structural Quality Optimization and Structural Vectoring? Log (SVL) provide geologists with better tools to define geometry and continuity—before wasting meters.

This case offers a clear lesson: structural insights are not just useful - they are essential. The cost of guessing is too high, and the path forward is clear: integrate structural intelligence early and drill smarter.

It’s time to move beyond guesswork in exploration. The Second Borehole Problem is avoidable. With the right structural insights, you can drill smarter, faster, and with higher confidence. Let’s discuss in the comments or reach out to us - let’s talk about your next drilling campaign.

References

Lawie, D. (2024) Valuating Ore Body Knowledge – The Financial Keystone for Mining Success in: Geohug podcast - https://www.youtube.com/watch?v=IFxtRdoVE6c

Maptek. (2018). Maptek Roy Hill smart mining partnership. Retrieved from:https://www.maptek.com/forge/september_2018/roy_hill_smart_mining_partnership/

Monteiro, R. N. (2005) Structural Inversion: Concepts, Procedures and Implications to Mineral Exploration/Exploitation. Internal ITSL Memorandum. December 20, 2005. 5 pgs.

Vektore (2012–2025) various references: Structural Geology in Mineral Exploration – various short courses to University of Western Ontario and clients; Structural Vectoring Log – SVL; Best Practices in Structural Exploration Geology and Standard Operating Procedures; Software development: Ore.node, vSTAR and vSTAR App.

#structuralgeology #orebodyknowledge #mineralexploration #valueofinformation #explorationgeology #structuralqualityoptimization #structuralvectoring

Michelle Ash Michelle Carey Dave Lawie Filipe Porto Eduardo de Oliveira Ferreira Hector R. Barrueto Marcos André Gon?alves Roberto Perez Xavier Luis Abadi Edson Franca Junior Glaucia Cuchierato Edson Ribeiro Celeste Queiroz Rogerio Alves Rodrigo Martins Roger Fitzhardinge Gaudius Colli Montresor