Question

Minerals lying near the surface can be extracted by a simple process called _____
A) Opencast mining
B) Underground mining
C) Quarrying
D) Drilling

Answer 1

Hint: This is a sub-type of an open-pit mining method or open cut mining or mega-mining. Minerals like chalk, china clay, sandstone, slate, clay, granite, marbles etc. are extracted by this method. This method is often regulated in certain places to reduce environmental impact.

Complete answer:
Let us analyze the given options:
Option A) Opencast mining – It is also called ‘open-pit mining’ and it is a surface mining technique for extracting minerals from the surface of the earth. In this method, huge deep pits are dug and the extraction is done in the open air. These can be significantly deep and hence, it is an incorrect option.
Option B) Underground mining – In this method tunnels are made under the ground for extracting minerals. It means that the ground under the surface of the earth becomes a hollow space while or after this type of mining. It is very deep and dangerous. Thus, this option is also incorrect.
Option C) Quarrying – It is a type of open cast mining but quarries are very shallow. This is the most appropriate method for extracting minerals that are extremely close to the surface of the earth. Thus, this is the correct option.
Option D) Drilling – Drilling is not a different kind of mining process. It is just a method of creating a hole in the ground so that it can facilitate mining. It is used in all the three options given above. Since it is not an actual mining method, this option is wrong.

Thus, the correct answer is Option (C) i.e, Minerals lying near the surface can be extracted by a simple process called quarrying.

Note: When these quarries are used up, they are abandoned and left as it is. These quarries get naturally filled with water and form lakes. These are called quarry lakes. These lakes can be very deep and surprisingly, very cold. It is not recommended for people to swim in quarry lakes as the unexpectedly cold water may cause shock to the muscles and even hypothermia.