SET 3 Flashcards
Finals
The most important underground mining method in practice today
Room and Pillar Mining
Unmined portion of the deposit, providing support to the roof
Pillar
Mixed out areas
Room
Self-supporting and only requires the addition of minimal artificial supports to achieve a stable opening
Rock
Applies to flat deposits having moderate to thick beds and to inclined deposits with thicker beds
Classic room and pillar mining
An adaptation of trackless mining to ore bodies where the dip is too steep for rubber-tired vehicles
Step room and pillar mining
Have large vertical heights where the mined-out space is hydraulically backfilled with tailings; combination of room and pillar and cut-and-fill- stoping
Room and pillar mining
Technique involves strategically removing the remaining pillars, causing the roof to collapse
Retreat Mining
It is a production opening in a metal mine where thicker and more irregular ore bodies occur
Stope
Are spaced randomly, located in low grade ore so that the high-grade ore can be extracted
Pillars
It is the oldest underground mining method; classified as a large-scale method in terms of total production
Stope and Pillar Mining
It can operate efficiently at angles up to 30ᵒ, it utilizes rail haulage
Inclined Stope and Pillar
100% of the ore in the stope is extracted; no natural pillars are left for support
Breast Stoping
Utilizes trackless haulage across the dip
Step Stope and Pillar
Equipment and Primary Opening used for relatively shallow depth
Conveyor belt; stope
Equipment and Primary Opening used for greater depth
Hoist; vertical shaft
Technique used when pillars are larger than necessary to provide good support
Pillar robbing and slabbing
Happens below the top of the orebody; accounts for 80% of the mine’s production
First Pass
Removal of the blasted ore; done by drilling and blasting the breast until the top of the orebody is reached
Second Pass
Blasting the benches. Benches are blasted and have been blasted horizontally with 1-3/4 in holes
Third Pass
An overhand method in which the ore is mined in horizontal slices from bottom to top and remains in the stope
Shrinkage Stoping
The required ore grade of the orebody for shrinkage stoping
High grade
This must be provided at the sill level into which the ore initially breaks and subsequently flows
Horizontal undercut
Method of extracting in large scale mining and has three variations
Sublevel Stoping
Most traditional method of Sublevel Stoping; drill radial patterns of drillhole is used
Blasthole method (Ring Drilling)