Zahurul
1 Answer
Colleen
Mining
The most widely used exploration technique is the drilling of probe holes. In this practice a drill with a diamond-tipped bit cuts a narrow kerf of rock, extracting intact a cylindrical core of rock in the centre. These core holes may be hundreds or even thousands of metres in length; the most common diameter is about 50 mm (2 inches).
The hole left after extracting the material would be the probe hole.
http://www.britannica.com/EBchecked/topic/477567/probe-hole
| 11 years ago. Rating: 1 | |
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