The actual position of the minerals (ore) to be extracted in mining are located by drilling. The position of the ore will be accurately known only if the drill hole is surveyed.

Many engineering projects require information about the underlying or surrounding rocks or soils. In these projects both the path of the drill hole and the orientation of rock/ soil samples may be required. This information is obtained by directional and tool-facing borehole surveys.

Blast Hole Arrays

If the blast-holes are not parallel, equal explosive loading of all the holes will produce excessive oversize where the holes are farther apart and excessive undersize where the holes are closer together. One answer to this problem is surveying the blast-holes.