Читать книгу Walking in the Yorkshire Dales: South and West. Wharfedale, Littondale, Malhamdale, Dentdale and Ribblesdale онлайн

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The dramatic rock wall of Malham Cove (Walk 20)

Neatly laid down in horizontal bands, the whole area, known as the Askrigg Block, was subsequently uplifted by earth movement, putting the Carboniferous strata of the block far above the younger rocks that lie to the south. The block tilts gently backwards, and whereas weathering has exposed the older limestones in the south west of the area, the more recent Yoredale rocks remain on top to the north east. The lines of fracture are dramatically evident in the three main Craven Faults, which cut across the southern part of the National Park. Giggleswick Scar – the line of towering cliffs overlooking the B6480 west of Settle – is part of the South Craven Fault, which continues its line south east towards Skipton. The Mid-Craven Fault is marked by a long line of cliffs of which Malham Cove and Gordale Scar are a part, while the North Craven Fault runs parallel to it at the southern lip of Malham Tarn. In a few places, the limestone of the block has been worn away to expose rocks from an even earlier era, known as the Ordovician, which, unlike the even, Carboniferous formations, are extravagantly crumpled and consist of slates, grits and mudstones. They can be seen in the quarries of Ribblesdale and around Ingleton, and are also exposed as an impervious basement layer in the southern valleys, perhaps most vividly in Thornton Force and along the Ingleton Falls.