Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/840

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Fig. 4.-Sections from Ulleswater to Haweswater. Distance six miles.

a. Skiddaw Slates. b, b. Traps and ashes of the Green-slate series. C. Slate-band of Cordale.

About a mile to the south of Heltondale Beck, and running parallel with it, is a second valley, called Cordale, the intervening ridge showing no rock-exposure. Both sides of Cordale are occupied by slaty beds, which strike E.N.E. and W.S.W., and have an apparent dip to the N.N.W. at 55°. These beds have been pretty largely worked for slate in the upper part of Cordale, and they consist partly of ordinary green slate and partly of a cleaved purple breccia, very similar to that worked in Borrowdale in all except its colour. There can be little doubt that these Cordale Slates, though not clearly represented in Aik Beck, are really the lowest slate-band in the series, and that they are a repetition to the south of the great slate-band which is worked at the head of Ulleswater, near Patterdale, and which is feebly represented in Arthur's Pike.

To the south of Cordale come on coarse felspathic ashes, still dipping northwards; and these are again followed by a varied and thick series of bedded traps and ashes, which occupy the hilly ground round Littlewater, directly to the north of the foot of Haweswater. In this region the traps and ash-beds succeed one another rapidly, and vary greatly in lithological characters, all, however, dipping N.N.W. is The ashes are sometimes fine-grained, sometimes brecciated, and sometimes amygdaloidal ; the traps are green or purple in colour, and are mostly highly porphyritic.

VIII. Lower portion of the Green-slate Series in the neighbourhood of Shap.

Owing either to folding or, more probably, to faults, in one instance at any rate, the Skiddaw Slates, and with them the lower beds of the Green Slates and Porphyries, are exposed in three distinct areas to the southeast of Haweswater. The best section, as exhibiting the relations of two of these areas, is to be found in the river Lowther and its tributaries, to the west and south-west of Shap (fig. 5). Commencing at Shap Abbey, there is shown in the bed of the stream, just above the Abbey Mill, an earthy trap with some felspathic ashes, both deeply reddened by the overlying conglomerates of Old Red Sand-