Modern-day mining exploration techniques are a far cry from the Gold Rush days when just about anybody with a shovel, a pan and a lot patience could try their luck prospecting for gold. Exploration is one of the riskiest sectors within the minerals industry as it is based on models or theories about where mineralisation may occur that have been developed from information that has been gathered about the area.
Today a wide range of sophisticated tools and technologies are used to identify which areas have the greatest potential before costly excavations begin. Examples include satellite imaging and computer software created specifically for the mining industry.
In fact, Australia leads the way in mining technology, with 60 percent of mining software used in operations around the world being exported from Australia.
Exploration techniques
The exploration techniques that are used will vary according to:
- which metals or minerals are being sought
- whether the exploration site is a 'greenfield' - an area that has not been investigated before - or a 'brownfield' - these areas are often adjacent to existing mine sites
- how large / accessible / advanced the exploration site is
- whether deposits are expected to be found exposed on the ground's surface or 'blind' ie. hidden under up to several hundred metres of soil and rock
Some of the most common tools and techniques used to test the potential of areas for mineralisation include:
- Remote sensing tools such as satellite imaging, seismic surveys, gravity surveys, magnetic surveys, aeromagnetic and radiometric surveys. Another process called induced polarisation involves passing an electrical current through the ground to measure the effect of rocks and minerals in its path.
Information gathered using this remotely sensed data will be used to identify target areas for more detailed exploration on the ground.
- Ground exploration tools and techniques such as geological mapping, historical data, drilling, clay, sand and gravel sampling, and chemical assays (ie. testing ore samples for valuable mineral content) help the geologist identify zones of mineralisation on the surface and at depth.
When a targeted area returns positive results further and more detailed exploration activities will focus on the identified mineralised zones to determine their extent and viability for further exploration and ultimately mining.
Investigate the resource From Exploration to Rehabilitation - the Life of a Gold Mine for further information about exploration and the techniques used to discover minerals.