Surface mining

Surface mining, including strip mining, open-pit mining and mountaintop removal mining, is a broad category of mining in which soil and rock overlying the mineral deposit (the overburden) are removed. In contrast to underground mining, in which the overlying rock is left in place, and the mineral removed through shafts or tunnels.

Surface mining began in the mid-sixteenth century and is practiced throughout the world, although the majority of surface mining occurs in North America. It gained popularity throughout the 20th century, and is now the predominant form of mining in coal beds such as those in Appalachia and America's Midwest.

In most forms of surface mining, heavy equipment, such as earthmovers, first remove the overburden. Next, huge machines, such as dragline excavators or Bucket wheel excavators, extract the mineral.

Types

There are five main forms of surface mining, detailed below.

Strip mining

"Strip mining" is the practice of mining a seam of mineral, by first removing a long strip of overlying soil and rock (the overburden). It is most commonly used to mine coal and lignite (brown coal). Strip mining is only practical when the ore body to be excavated is relatively near the surface. This type of mining uses some of the largest machines on earth, including bucket-wheel excavators which can move as much as 12,000 cubic meters of earth per hour.

Stol

Stol may refer to:

See also

Åstol

Åstol is a locality situated south of Tjörn Municipality (close to Marstrand), Västra Götaland County, Sweden with 210 inhabitants in 2010. Åstol has always been a center for fishing, especially for herring-fish, mackerel and flatfish. This is mainly due to the location of the island.

Åstol is also well known for its harbour. The harbour has an excellent location and is protected against wind and waves. Åstol also has a harbour for visitors, and is located along both south and north side of the harbour. The port has approximately 50 harbour spots for visitors. The depth of the harbour is 4,5 m which makes it possible for big boats such as steam-boats and galleons to add.

Located in the center of the island you can find a small "Handelsbod"/store were you can buy almost everything that is required to live on the island. There is also a restaurant, café and a kiosk. Another thing that makes Åstol special is their smokehous, called Åstols Rökeri.

Åstol's smokehouse contains 6 different sections. The restaurant, "Iseriet", a beer garden called "Perrys Bar", a fish store, Björn's Pictures and the smokehouse. At "Åstols Rökeri" you can order smoked eel, herring, mackerel, salmon and shrimp.

Stol (Serbia)

Stol (Serbian Cyrillic: Стол) is a mountain in eastern Serbia, near the town of Bor. Its highest peak has an elevation of 1,156 meters above sea level. Like nearby Veliki Krš and Mali Krš, Stol has a number of pronounced karst formations. There is a mountain hut with around 35 beds, maintained by the mountaineering society "Crni vrh" from Bor.

References

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