Problems in coal mining

Coal mining cannot be done everywhere with coal, due to certain restrictions.

Problems

Dip of strata

Due to current machinery, a permament feedback is required.

Faulting

If a fault hits a rock with a coal seam inside, the coal seam moves. Machinery trying to mine the coal may not be able to get at it if the coal has faulted off anywhere but to the side (if it is above or below it cannot manage this). There is a short supply of good machines for underground mining.

Water table

If the water table is too low, the mine is full with water. While mining, water needs to be constantly pumped out and this is expensive.

Washout

If a distributary or river changes course and cuts into the swamp material that will form coal, the coal seam is not fully formed and there may be a problem with mining itclarifyme.

Thickness of seams

If the seams are too thin there may be an economic problem with mining it (it is worth less than the cost of the workers or petrol and is worthless.

plitting of seams

If the seam splits, due to a delta collapsing, sand and silt sediments pile up on top until that area is covered by coal again. This may make all or part of the coal seam [http://en.wiktionary.org/wiki/uneconomic uneconomical] to mine (as it is too thin).