coal seam
coal bed

The reason taken for this new plan was to save the coal seam.

The coal seam itself is 6 to 8 feet thick.

Thus, where oil and gas deposits are found, there will often be coal seams above them.

The coal seams dipped at 1 to 4.5 towards the south.

The coal seam was thick, nearly two and a half meters.

He proposes that the coal seams should be worked in the advance.

It gave us some of the thickest coal seams in America.

There are also numerous coal seams within the sequence, most of which have been worked.

There is a coal seam about 10 miles away.

These were and are economically important coal seams in the Appalachian area.

The coal seam was about 2,000 feet below the portal entry.

Coal seams visible on the surface are followed deep underground.

"Every year we've had to go deeper to follow the coal seams.

Most of the gas produced in Queensland now comes from coal seams.

Mines 16 and 18 exploited a coal seam 4 to 7 feet thick.

Miners dig tunnels down into the earth to find coal seams.

Fire clay is often found close to coal seams.

It also occurs as a result of mine or coal seam fires.

Discovery of sizeable coal seams further increased interest in the area.

Second Street was the northernmost tunnel through the coal seam.

A few coal seams are visible in the banks.

To fill coal seams of up to 70 feet wide, hills in the area are leveled.

Beneath them the coal seams are buried and preserved for our miners today.

However, small fires were constantly erupting in the coal seams.

Corey was mining clay from both above and below the coal seam.