Foreign placer exploration technology

Placer exploration methods There are two methods used for placer exploration abroad, including shallow well method and drilling method [5].

Shallow wells are widely used in the exploration of placers with low water content buried in ore bodies, and as a verification method for placer drilling. However, land placer deposits are mostly distributed in river valleys of modern water systems, with abundant groundwater and rocky

Due to high permeability, safety work such as ventilation, drainage, lighting, and support during shallow well construction is not easy to ensure, combined with low efficiency, high labor intensity, high cost, and difficulty in maintaining sampling quality. Therefore, shallow well exploration in recent years has been decreasing.

The drilling method used for placer exploration began in 1858, when the Dutch engineer Akerlinga designed a sand drill to explore the placer tin deposits below the diving layer on Banga Island in Indonesia. It was successful, hence the name " Work harder".

Since then, all countries in the world have used Panga drills to explore placers, and further developed and improved its technology in practice. In addition to shift drilling, in placer exploration, other drilling methods include vibratory rotary drilling, core rotary drilling without flushing fluid, permafrost hammer percussion rotary drilling, and large-diameter percussion. Grab bucket drilling method an