 It is from the Scottish border, south of Southdean.The ground beneath the city is formed from Carboniferous strata of the Middle Pennine Coal Measures Group—a suite of sandstones, mudstones and coal seams which generally dip moderately eastwards.To the west of the city are the Upper Pennine Coal Measures and further west again the sandstones and mudstones of the Stainmore Formation, the local equivalent of the Millstone Grit.