Coniston Beds

Coniston Beds, a great series of rocks upwards of 5,000 ft. thick, partly Ordovian and partly Silurian in age, which occupy a large area in Westmoreland. The lower division is the Coniston limestone, which rests on the great Ordovian volcanic series of the district. It contains corals, brachiopods, and trilobites, many of which are identical with those of the Bala limestone in North Wales, and in Furness it occurs as the Ireleth limestone. Above it comes a great series of dark grey coarse flags or sandy mudstones, the Coniston Flags, followed by tough sandstones and greywacke, the Coniston Grits. These beds contain graptolites and other fossils similar to those of the Denbighshire Grits and the Lower Wenlock series of the Silurian.