Which mining method is used when ore is found in flat, tabular deposits?

Solution (By Examveda Team)

Definition of Room and Pillar Mining:
Room and Pillar mining is an underground mining method used primarily for extracting flat or gently dipping, tabular ore bodies. In this method, "rooms" of ore are mined out while leaving behind "pillars" of unmined material to support the roof of the mine. The layout resembles a grid-like pattern of openings and pillars.

Correct Answer: Option C: Room and Pillar
The correct answer is Option C: Room and Pillar because this method is specifically designed for flat, tabular ore deposits. The geometry of the method allows for efficient ore recovery while maintaining structural integrity through the use of support pillars.

Room and Pillar is commonly used in coal mining, as well as in deposits of potash, gypsum, and salt. The design of the pillars is based on rock mechanics principles to ensure they can support the overburden without collapsing. In some cases, after primary extraction, pillars may be partially or fully removed in a process called "pillar recovery" or "retreat mining."

Explanation of Other Options:
Option A: Shrinkage Stoping
Shrinkage stoping is used for steeply dipping ore bodies, not flat ones. It involves mining upward and storing broken ore in the stope to provide a working platform.

Option B: Block Caving
Block caving is suitable for massive, lower-grade ore bodies that are mined by undercutting and allowing the rock to cave under gravity. It is not ideal for thin, flat deposits.

Option D: Sublevel Caving
Sublevel caving is used in steeply dipping ore bodies and involves controlled caving of both ore and waste. It is not optimal for flat, tabular deposits.

Conclusion:
Therefore, the correct answer is Option C: Room and Pillar, as it is the most suitable mining method for extracting ore from flat, tabular deposits while maintaining ground stability through the use of pillars.