Underground mining (or subsurface mining) Underground mining is best suited to extract minerals that are located deep under the surface of the earth. Common minerals extracted using underground mining include gold, lead and silver.
What are the three types of underground mining?
2: Underground Mining Methods. Underground mining methods become necessary when the stripping ratio becomes uneconomical, or occasionally when the surface use of the land would prohibit surface mining. Underground methods are traditionally broken into three classes: unsupported, supported, and caving methods.
What is underground metal mining?
When any ore body lies a considerable distance below the surface, the amount of waste that has to be removed in order to uncover the ore through surface mining becomes prohibitive, and underground techniques must be considered. …
How dangerous is underground mining?
Working in coal mines is dangerous — miners have to deal with toxic gases, plus the threat of being crushed, drowned, or injured from fires and explosions.
How long do miners stay underground?
Miners usually work shifts, and they can be on for 10 days in a row. Some head down before sunrise and return anywhere from seven to 12 hours later.
What is stope and pillar?
Stoping, in mining engineering, the opening of large underground rooms, or stopes, by the excavation of ore. A common open-stoping method is room-and-pillar mining, in which pillars of ore are left standing to support the rock over a flat-lying ore body. In many mining operations, stopes must be supported artificially.
Which are the two main techniques of mining?
Primarily, there are two types of mining methods being used for the extraction of minerals and ores – surface/opencast mining and underground mining. The choice of method is largely determined by factors such as depth, geology of the mineral deposit and the cost of equipment.
What are the important methods of mining?
A Guide to the Four Main Methods of Mining
- Underground Mining. Relatively costly and frequently used to get to deeper deposits, underground mining involves digging down into the earth and creating tunnels and shafts that reach the deposits of resources.
- Surface Mining.
- Placer Mining.
- In-Situ Mining.
- Sources.
What are the different types of underground mining?
When the ore bed is completely excavated, these pillars can be harvested for additional ore; a process called ‘retreat mining’. Coal, iron, copper, talc, cobalt, dolomite, and potash mines In this technique, ore is excavated in horizontal slices, after which, the stope (mined-out space) is filled with waste rock and cement (called a back fill).
Which is the correct way to enter an underground mine?
The entry from the surface to an underground mine may be through a horizontal or vertical tunnel, known as an adit, shaft or decline. Underground mining is practical when: The ore body is too deep to mine profitably by open pit. The grades or quality of the orebody are high enough to cover costs.
How is block caving used in underground mining?
Block caving is a technique in which the weight of the overlying rock is itself used to fracture an ore deposit into small pieces, which can then be collected. In this method, a large ore deposit is divided into different sections, or ‘blocks’.
How is mining carried out in an ore deposit?
In this method, mining is carried out in an ore deposit, leaving behind some of the ore in the form of columns to support the roof and prevent it from collapsing. Thus, it results in the formation of spaces called ‘rooms’, where the ore is excavated with ‘pillars’ of ore distributed throughout.
