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Notes on the Physiography and Glaciology of North-East Carnarvonshire

Published online by Cambridge University Press:  01 May 2009

S. A. Billinghurst
Affiliation:
Academic Diploma in Geography (Lond.).

Extract

The present notes have accumulated since 1923 during a survey of the solid geology of the region between the western slopes of the Vale of Conway and Moel Wnion, including the district around Tal y Fan mountain, Foel Lwyd and Drosgl, and extending northward to the coast. The glacial deposits and alluvium have been mapped on the 6 in. scale, and a sketch-map is here given (Fig. 1). The areal distribution of the drift is described and an attempt is made to account for some of the glacial and physical features. Some notes are added upon the general character and origin of the Conway Valley.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1929

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References

page 147 note 1 Dewey, H., “On the Origin of some Land-forms in Carnarvonshire, North Wales,” Geol. Mag., 1918, p. 149.Google Scholar

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page 157 note 1 A micro-section confirmed this determination. The rock consists chiefly of a microfelsitic groundmass with much calcite, secondary muscovite and quartz, the latter occurring in thin veins with some chlorite, decomposed orthoclase and plagioclase with pericline twinning, and pink garnets, 1 to 3 mm. diameter.

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