Different exploration methods are applied to identify and map information about minerals.
Prospecting: The initial stage in most exploration programs, prospecting is the process of recognising and identifying new areas considered to have potential for hosting economic concentrations of a mineral resource (economic mineralization). Prospecting often results in the creation of a geological map which forms a major reference source for other more costly techniques
Geochemical surveys: These are undertaken to obtain specific chemical information on the rocks or soils of an area. They require the collection of rock or soil which is analysed by a laboratory for selected elements or compounds. Geochemical survey techniques are rock-chip sampling, stream sediment sampling and soil sampling.
Geophysical surveys: These measure contrasts in the physical properties of rocks resulting from magnetic, gravitational, electrical and electromagnetic fields, or seismic waves. They may be performed on the ground, in the air, at sea or from space (i.e. by satellite) at scales ranging from regional-scale to small-scale localised surveys. Information generated is typically processed using computer software packages to generate a wide range of colourful images that reflect different geophysical characteristics of the rocks.
Exploration drilling: this enables rock samples to be obtained from close to surface to depths exceeding 1000m to check the geological and geochemical character of the sub-surface geology. Typically, the drilling rig is vehicle-mounted and supported by a second truck that carries drilling supplies and maintenance equipment. A wide variety of drilling techniques may be used in a mineral exploration program depending on the characteristics of the site, target mineral and exploration drilling budget.
Bulk sampling: this may be undertaken by an explorer in order to obtain a sufficient volume of material to enable specific and meaningful test-work to be performed, often as part of the pre-feasibility and feasibility investigations for mining. Bulk sampling typically involves the excavation of trenches (costeans) or test pits from which a large sample volume is collected.