Having worked in coal mines in South Yorkshire, West Yorkshire and the Selby Coalfield and my own research, it is obvious that coal seams are all different. ‘Dry’, ‘dusty’, ‘wet’, ‘gassy’ and ‘fiery’ are some of the descriptions you may use for the seam you are working in at the time. Gassy and fiery often mean the problem of spontaneous combustion is a major problem associated with these seams. As you can see below, Yorkshire has it’s fair share of these seams.
- Shafton
- Stanley Main
- High Hazels
- Barnsley Bed
- Dunsil
- Parkgate
- Thorncliffe
- Silkstone
- Beeston
The South Yorkshire and West Yorkshire coalfields and seams are very different. Coal seams vary not only by thickness and quality but even in name. Below is a section of all the coal seams in Yorkshire, starting with the Shafton seam nearest the surface.
The Yorkshire Coalfield is made up of two quite distinct areas. The world famous, Barnsley Bed Seam, also known as the Main Seam in South Yorkshire, was the prime seam in the South Yorkshire area. Collieries sunk to work the Barnsley seam were called Main, e.g. Cadeby Main, Wath Main, etc. The Barnsley seam changes character and splits to the north of the coalfield. It becomes the Warren House with a poor seam called the Barnsley Rider above the Warren House.
The Barnsley seam was discovered in the Selby area very much later in the 1960s, which started the Selby Coalfield development in the 1970s
The coalfield is split in an East / West line running from Woolley, in the West, to Askern in the East. This line was the dividing line of of two distinct coal swamps formed around 320 / 300 million years ago in the Carboniferous era.
The northern edge of the Yorkshire coalfield is situated North of Leeds and also has an East / West fault line. With the movement eastwards, victorian mining engineers encountered problems with the increasing depth of pits. in addition, a major geological problem was to cause more mining problems, vast expense and huge financial risk. This problem was the Magnesian limestone or as it is also known, The Permian Layer. This layer of rock is from the later Triassic and Jurasic geological era, from 130 million years ago.
This unbroken layer of Permian Limestone starts on the western outskirts of Nottingham and continues northwards up to Durham. The first pit to be sunk to work beneath this layer of limestone, which was also the deepest at the time was Denaby Main Colliery, mid way from Mexborough and Conisborough. The pit was sunk in 1867 to 457 yards to work the 108 inch Barnsley bed seam by the Pope and Pearson company, who sank the West Riding Colliery in Altofts, near Castleford. This layer of limestone, along with it’s water, was one of the major problems to be overcome during the development of the pits in the Doncaster area and when the Selby Coalfield was planned.
Selby Superpit 