|Hart-Davis, Adam. Deepest Mine. BBC and Open University, 2002.||"The deepest mine in this region (Witwatersrand) is currently Western Deep mine, a network of tunnels which penetrates 3.5 km into the Earth's crust."||3500 m|
|Structure of the Earth. Geography Exchange, 7 March 2003.||"The deepest mine in the world is only 3.3 km deep, and nobody has ever been able to drill down further than 15 km."||3300 m|
|How deep is the deepest mine? Grid Club, 2003.||"The deepest mine is a gold mine in South Africa; in 1977 the Western Deep Levels reached a depth of 3,581 meters.||3581 m|
|Lotsberg, Gunnar. Mines. The Worlds Longest Tunnel Page, 2003.||"It has the world's deepest mine, 3585 m below surface at the East Rand mine."||3585 m|
|Holt, Rinehart, & Winston. Environmental Science. 1996: pg 210 - Figure 8.17.||"This open-pit copper mine in Bingham, Utah is wider than 35 football fields and more than twice as deep as the Empire State Building."||896 m|
Several types of mines can be found around the world. Mines that might be considered the world's deepest are either open-pit or vertical shaft mines. Vertical shaft mines hold the record for being the deepest mines in the world. Most are located in South Africa due to its abundance of diamond and gold deposits. As of 2003 the deepest mine is the East Rand mine at 3585 meters, but as technology improves and the search for natural resources continues many mines are constantly being deepened. In the next few years, the Western Deep mine will reach 5 km.
Many problems arise when digging so deep into the Earth. The most obvious is the heat. For example, at 5 km the temperature reaches 70 degrees Celsius and therefore massive cooling equipment is needed to allow workers to survive at such depths. Another problem is the weight of the rock. For example, at 3.5 km the pressure of rocks above you is 9,500 tones per meter squared, or about 920 times normal atmospheric pressure. When rock is removed through mining this pressure triples in the surrounding rock. This effect coupled with the cooling of the rock causes a phenomenon known as rock bursts, which accounts for many of the 250 deaths in South African mines every year.
Yefim Cavalier -- 2003