Prospection (géologie)

Prospecting is the first stage of the geological analysis (followed by exploration) of a territory. It is the search for minerals, fossils, precious metals, or mineral specimens. It is also known as fossicking. Traditionally prospecting relied on direct observation of mineralization in rock outcrops or in sediments. Modern prospecting also includes the use of geologic, geophysical, and geochemical tools to search for anomalies which can narrow the search area. Once an anomaly has been identified and interpreted to be a potential prospect direct observation can then be focused on this area. In some areas a prospector must also make claims, meaning they must erect posts with the appropriate placards on all four corners of a desired land they wish to prospect and register this claim before they may take samples. In other areas publicly held lands are open to prospecting without staking a mining claim. The traditional methods of prospecting involved combing through the countryside, often through creek beds and along ridgelines and hilltops, often on hands and knees looking for signs of mineralisation in the outcrop. In the case of gold, all streams in an area would be panned at the appropriate trap sites looking for a show of 'colour' or gold in the river trail. Once a small occurrence or show was found, it was then necessary to intensively work the area with pick and shovel, and often via the addition of some simple machinery such as a sluice box, races and winnows, to work the loose soil and rock looking for the appropriate materials (in this case, gold). For most base metal shows, the rock would have been mined by hand and crushed on site, the ore separated from the gangue by hand. Often, these shows were short-lived, exhausted and abandoned quite soon, requiring the prospector to move onwards to the next and hopefully bigger and better show. Occasionally, though, the prospector would strike it rich and be joined by other prospectors and larger-scale mining would take place.