Mining  Surface Mining

Surface Mining

Surface mining is a form of mining in which the soil and the rock covering the mineral deposits are removed. It is the other way of underground mining, in which the overlying rock is left behind, and the required mineral deposits are removed through shafts or tunnels.

Surface mining is basically employed when deposits of commercially viable minerals or rock are found closer to the surface; that is, where overstrain (surface material covering the valuable deposit) is relatively very less or the material of interest is structurally unsuitable for heavy handling or tunneling (as would usually be the case for sand, cinder, and gravel).

Where ever minerals occur deep below the earths crest or the overburden is too thick or the mineral occurs as strands in hard rock, Underground mining methods are employed to extract the valuable mineral deposits. Surface mines are naturally extended until either the valuable deposit is exhausted, or the cost of de-cresting larger volumes of overburden makes further mining an uneconomic option to shoulder.

In most types of surface mining, heavy paraphernalia's such as earthmovers are utilized. They 1st remove the overburden the soil and rock above the deposit. Then followed by the huge machines, such as dragline excavators, extract the mineral.

Types of surface mining

Strip mining: Strip mining is the practice of mining a layer of mineral by 1st removing a lengthy strip of overlying soil and rock (commonly known as the overburden). It is most frequently used to mine coal (especially lignite [citation needed] coal) or tar sand. Strip mining is barely practical when the ore body to be dug out is relatively near the surface. This mode of mining employs some of the largest machines in use on earth, together with bucket-wheel excavators which can move as much as 12,000 cubic meters of earth per hour.

Open-pit mining: Open-pit mining refers to a technique of extracting rock or minerals from the earth by their deduction from an open pit or borrows. Although open-pit mining is sometimes erroneously referred to as "strip mining", the 2 methods are different.

Mountaintop removal: Mountaintop removal mining (commonly termed as MTR) is a relatively new form of coal mining that engages the mass restructuring of earth in order to get in touch with the coal seam which is as deep as 1,000 feet below the surface. It is utilized where a coal seam protrusions all the way around a mountain top. All the rock and soil higher than the coal seam are removed and the soil placed in flanking lows such as hollows or ravines. Mountaintop subtraction replaces previously steep landscape with a relatively plane surface.

Dredging: Dredging is a method frequently used to bring up submerged mineral deposits under water. Although dredging is usually employed to clear or make bigger waterways for boats, it can also recuperate significant amounts of underwater minerals which are relatively efficient and cheaply extracted.