Friday, February 1, 2013

Lake District scenery

In addition to its main outcrop lying athwart the central and highest part of the luxury themed boutique hotels in the lake district , the Borrowdale Volcanic beds also occur along the northern fringe beyond Skiddaw. Their distinctive character and the way they have influenced the scenery can be seen when one is passing through the strip of country between Cockermouth  and Caldbeck. The hill above Bothel Crags with the Roman fort of Caermote on its eastern flank, and the isolated conical hill of Binsey with its bare rocky slopes, are but two of the distinctive topographic features associated with the harder rock in this foot. Hill zone. Farther east the volcanic beds also form the northern rim of the Caldbeck Fells, and beyond the eastern edge of the Skiddaw mass they make their final appearance on Eycott Hill, overlooking the marshy trough of the Mungrisdale Valley.

The lavas here have a very distinctive appearance, with large elongated crystals of felspar running throughout the rock.

Other softer beds are present so that the western slope of the hill has a markedly terraced appearance. On top there is a jumble of bare rock ribs with intervening marshy hollows, a reminder that at this northeast extremity of its outcrop the Borrow¬dale Volcanic Series does not bow out without making its own distinctive con¬tribution to the landscape. The country of the southern fringes of the Lake District, the part first seen by visitors making their way from the motor way near Kendal towards the innermost valleys and fells, has a more subdued appearance. Apart from the flanks of the high plateau of the Eastern Fells around Staveley the land is nearly all below a thousand feet.

Much of the area known as High Furness, between Coniston Water and Windermere, is typical of a countryside developed on a succession of different rock types, mainly of Silurian age. To Jonathan Otley this was greywacke country, so named from the prevalence of gritty material in the rocks. Individual beds with distinctive characteristics have been given local names, like the Stockdale Shales from the hamlet now a single farm lying in a tributary valley of Long Sleddale . Similarly the Bannisdale Slates refers to the valley in the Eastern Fells where they are typically developed, while the Brathay Flags are associated with the estate at the head of Lake Windermere.

At the base of the whole series is the Coniston Limestone, seldom more than two hundred feet thick and consequently forming a very narrow outcrop. In spite of its name there are only impure limestone beds, and calcareous mudstone would be a more descriptive title. In areas where lime is scarce, small quarries were opened up in the past and the rock burned for agricultural purposes. At Stockdale Farm in Long Sleddale an old lime kiln stands in the farmyard within a few yards of the outcrop on the other side of the stream.

Although the actual outcrop is narrow, the persistence of the Coniston Limestone makes it a good marker bed separating the older Borrowdale Volcanic rocks from the newer Silurian strata above. Because of the limited thickness of the bed, the effect on the landscape is minimal. Towards the head of the Kent mere valley near Kent mere Hall  the outcrop coincides with the col of the Garburn Pass which leads across into Troutbeck. Similarly parts of the pass which runs across to Long Sleddale from Stile End also coincide with the lime¬stone. Both cols owe their present form to ice erosion, but undoubtedly the weaker strata here compared with the hard volcanic rocks to the north helped erosion.

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