Question

(u) 200
erals that lie at shallow depths are taken out by removing the surface layer, this
known as​

Answer 1

Answer:

Minerals that lie at shallow depths are taken out by removing the surface layer; this is known as open-cast mining. Deep bores, called shafts, have to be made to reach mineral deposits that lie at great depths. This is called shaft mining.

Explanation:

Minerals can be extracted by different processes, which are as follows:

• Mining: The process of taking out minerals buried under the rocks is called mining. There are two main methods of mining, viz. open-cast mining and shaft mining.
• Open Cast Mining: When minerals are taken out by removing the surface layer, the process is called open-cast mining. Minerals which lie at shallow depths are extracted by this process.
• Shaft Mining: When deep bores (called shafts) are made to reach the mineral deposits at great depth, the process is called shaft mining.
• Drilling: When deep wells are bored to take out the mineral, the process is called drilling. Petroleum and natural gas are extracted by this method.
• Quarrying: When minerals are simply dug out from near the surface, the process is called quarrying.