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V.—On some Physical Changes in the Earth's Crust
Published online by Cambridge University Press: 01 May 2009
Extract
On the western flanks of the Malverns, the Upper Silurians are folded in several great anticlinals and synclinals, formed parallel to the axis of the Hill itself. To the west of Ledbury and again near Woolhope these contorted strata dip beneath the Old Red Sandstone, which, as computed by Phillips, has a maximum thickness of 8000 feet, that of the Upper Silurians being 2690 feet.
The thickness of the strata of which the Longmynd is formed has been estimated by the Government Surveyors at not less than 26,000 feet, as exposed in their highly inclined edges; the beds dipping at an average inclination of 60° to the W.N.W. They thus appear as if they had been tilted by pressure against the more ancient rocks of the Caer Caradoc Range.
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References
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