Long Excursion to the Lake District
123 LONG EXCURSION TO THE LAKE DISTRICT. AUGUST 7TH TO 17TH, 1920. REPORT BY J. FREDElUCK N. GREEX, B.A., F.G.S., Director o] the Excursion. PLAn: 5. OWI~G to difficulties of accommodation the excursion, originally planned to include visits to the southern part of the Lake District, had to be restricted to places readily accessible from Keswick. While the glacial geology, physiography and minerals were not neglected, the chief object was to examine questions of vulcanicity, sequence and structure. The main controversial points were enumerated by the Director at an evening meeting on August 8th, when he gave a brief account of the points on which his 'views differed from those of earlier investigators. The foundation of his case lav in the identification of the .-, flow breccia'S," as lavas instead of tuffs or agglomerates, since this was the basis of his mapping. In this way he had arrived at a sequence in the volcanics, which had so far proved effective wherever applied. The larger part of this sequence was repeated ten times between Keswick and Coniston, so that the maximum thickness of the Borrowdales was probably only about 3,500 feet. This major folding was accompanied by concertina folding, especially in the softer rocks, in which the folded sheets often tended to horizontality. The Devonian folds were arranged fan-wise about an anticlinorial axis through Scawfell and the south of the Helvellyn mass. Working along these lines he had come to the conclusion, contrary to that of the Survey and the Cambridge School, that the upper and lower junctions of the Borrowdale Series were, as a rule, unfaulted, the volcanics resting conformably on the Skiddaws and being covered with a strong unconformity by the Bala Coniston Limestone series.
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