Multi-Scale Thinking in Vein Modeling

The Role of Resolution and Scale in 3D Geological Modeling

Resolution and grid cell size are critically important when it comes to 3D geological modeling. In vein modeling, scale refers to how vein dimensions – such as length and thickness – change across different observation levels, from outcrop and mine scale to regional scale. It also reflects how modeling software handles scale, different data types like drillholes and samples, and modeling parameters such as triangle size or snapping tolerance. All of this influences model realism, from small mineralized shoots to large structural systems.

Managing Multi-Scale Detail in Vein Models

In practice, this means managing multi-scale detail, from broad fault systems down to individual ore shoots, while maintaining consistency in geometry and grade distribution. In K-MINE, vein models are built using drillhole data, surface information, and structural controls such as fault surfaces. This allows us to bridge scales, linking discrete point data and continuous geological surfaces.

Implicit Vein Modeling and Scale Considerations

In implicit vein modeling, scale becomes especially important. Narrow veins represent a small-scale challenge, while large faults operate at a large-scale. Mathematical interpolation methods – such as radial basis functions or kriging – define veins as isosurfaces, while structural data constrains geometry. Often, the most realistic results come from hybrid methods, combining implicit and explicit modeling.

Understanding Scale-Dependent Continuity

It is also important to note that continuity is highly scale-dependent. At a large scale, structural continuity may extend for kilometers. Within that structure, vein continuity may persist only for tens of meters. Because gold is often concentrated in narrow veins, grade continuity can appear low globally but strong locally. For this reason, continuity should be discussed at multiple scales.

Scale in Mineral Resource Estimation

When we move into mineral resource estimation, scale again plays a defining role. A scoping study is generally based on inferred resources, with wide drill spacing and global continuity assessment. A pre-feasibility study requires higher confidence, supported by closer drill spacing and Indicated to Measured Resources. At this stage, continuity can be assessed at a local scale, while Inferred Resources are excluded from economics. By the feasibility stage, modeling reaches maximum detail.

Scale-Related Challenges and Data Integration

Scale-related challenges often stem from choosing the wrong level of detail. Using mismatched data scales leads to misinterpretation. There is always a detail trade-off between resolution and coverage. Scale-related errors directly affect model reliability and risk. Integrating data across multiple scales remains a key challenge. High-resolution data increases costs, often with diminishing returns. Project teams must balance technical ideals with practical constraints. Modern software like K-MINE supports scale decisions, balancing resolution, coverage, and reliability.