Durham Coalfield
The Durham Coalfield is a coalfield in north-east England. It is continuous with the Northumberland Coalfield to its north. It extends from Bishop Auckland in the south to the boundary with the county of Northumberland along the River Tyne in the north, beyond which is the Northumberland Coalfield.
The two contiguous coalfield areas were often referred to as the Durham and Northumberland Coalfield or as the Great Northern Coalfield.
Geology
The following coal seams are recorded from the Durham coalfield. They are listed here in stratigraphic order with the youngest at the top and the oldest/deepest at the bottom:Upper Coal Measures
Middle Coal Measures
Lower Coal Measures