The coal seams worked in the
South Yorkshire Coalfield
The South Yorkshire Coalfield is so named from its position within Yorkshire. It covers most of South Yorkshire, West Yorkshire and a small part of North Yorkshire. The exposed coalfield outcrops in the Pennine foothills and dips under Permian ro ...
lie mainly in the middle
coal measures within what is now formally referred to as the
Pennine Coal Measures Group
The Pennine Coal Measures Group is a lithostratigraphical term referring to the coal-bearing succession of rock strata which occur in the United Kingdom within the Westphalian Stage of the Carboniferous Period. In formal use, the term replace ...
. These are a series of
mudstones
Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from ''shale'' by its lack of fissility.Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York ...
,
shales
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g., kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especial ...
,
sandstones
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed o ...
, and
coal seam
Coal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extrac ...
s laid down towards the end of the
Carboniferous
The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...
period between about 320 and 300 million years ago. The total depth of the
strata
In geology and related fields, a stratum (: strata) is a layer of Rock (geology), rock or sediment characterized by certain Lithology, lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by v ...
is about .
The list of coal seams that follows starts at the shallowest seam and proceeds downwards with the outcrops occurring progressively further west until the deepest coal seam, the Silkstone Seam which outcropped at the western edge of the coalfield.
The thicknesses and depths of each seam are not given as they vary across the coalfield.
Seams
Sources
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Further reading
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External links
Yorkshire Coalfield Geology- with depths of the seams at
Kiveton, and a map showing the depth of the Barnsley Seam across the coalfield; see also depths of the seams at
Dinningtonbr>
and
Thurcroft
Thurcroft is a village and civil parish situated south-east of Rotherham in the Metropolitan Borough of Rotherham in South Yorkshire, England. From 1902 to 1991, it was a mining community. It has a population of 5,296, increasing to 6,900 at ...
br>
{{Coal mining in Yorkshire
Geology of South Yorkshire
Mining in South Yorkshire