Lesson 3- Surface Mining Method Flashcards
In the United Kingdom and South Africa, a coal mine and its structures are is called as “____” which also refers to an underground coal mine in Australia.
colliery
___, ____, _____of the coal seam are the factors that are taken
into account while selecting the mining method for coal extraction.
Depth, density, and thickness
This method recovers a greater fraction of the coal deposit than underground methods since more coal seams are exposed for extraction using high capacity heavy equipment in this approach.
open pit or open cast.
Open Pit Mining Cycle
- Removal of overburden
- Extraction and Hauling of Coal
In Philippines, ____ of the country’s coal production is produced by Semirara Mining Corporation, an open pit mine and the largest coal producer in the country.
92%
In this method, coal seams are exposed by removing the surface or overburden above them in long strips.
Strip Mining
The overburden taken out from the first strip is deposited outside the mining area. This process is referred to as _________.
out-of-pit
dumping
________ and ________mining are the two forms of strip mining, which is often used to extract coal and lignite.
Area strip mining and contour strip mining
In contour strip mining, ________ or ________ are deployed to take away huge amounts of ground material in terraced strips for extracting coal from a seam on a hill.
bulldozers or power shovels
Commonly used on flat terrain to extract deposits spread over a large area.
Area strip mining
This method is applied for mineral deposits situated near the peaks of a mountain but too deep to be extracted by drilling tunnels from the sides. This technique is widely used in the Appalachian coal fields of West Virginia, Kentucky, Virginia and Tennessee in the US. This method involves removal of the mountaintop overlying the coal seam by blasting and hauling.
Mountain-top removal
In this method, ore is removed by digging a pit in the ground. It is normally used when the rock layer above the ore is too weak to allow underground tunnels and when ore deposits are lying under thin rock which can be easily removed by digging benches.
Open-pit Mining
In this technique, circular benches are dug around the circumference of the pit to remove ore from the sides. When ore can no longer be removed from one bench, a new one is dug at a lower level.
Open-pit Mining
The equipment used for open-pit method is mostly restricted to __________, and _______, though conveyors can quicken the process.
dump or haul trucks, and shovels
This refers to a method of removing coal, clay, phosphate, oil-shale, etc. from thin seams exposed in deep trenches or high-walls in strip mines using an ______.
Auger mining, auger
