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Title: 8 published articles on geology
Author: Reynolds, Doris
Awarding Body: University of London
Current Institution: Royal Holloway, University of London
Date of Award: 1937
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In 1911 Dr. W. B. Wright briefly described the felspathized quartzite blocks in the hornblendite of Port Easdale, Kiloran Bay, Colonsay, Hebrides. He showed that the exposures provide a conclusive demonstration that the action of hornblendite magma on quartzite xenoliths was to convert them to alkali-felspar and quartz, so that in the final stage ‘one can recognize in numerous angular and rounded patches of felspathic material, without visible xenolithic core, the ghosts of former masses of quartzite'. Twenty-five years have elapsed since the publication of Dr. Wright’s account, yet the importance of the record appears to have passed unnoticed. The purpose of this paper is, therefore, to recall the occurrence ; to amplify Dr. Wright’s description with additional observations and petrological and chemical detail ; and to emphasize the petrological significance. Stimulated by Dr. Wright’s description, Dr. Holmes and I paid a preliminary visit to Colonsay in 1934. Finding much of interest we returned in 1936 and, in order that no detail should be overlooked, remapped the small intrusions of Port Easdale on the scale of 54 inches to the mile. For this purpose the coastline, with its disconnected rocky outcrops, had to be remapped. As a result of our visits much additional evidence of first-class petrological importance has been obtained. We propose to deal with this evidence in a series of papers of which the present communication, restricted to the phenomena attending the transfusion of quartzite, forms the first. The sedimentary rocks, which constitute the major part of the island of Colonsay, consist of a folded, crumpled, and cleaved series of phyllites, limestone, mudstones, grits, and conglomerates, regarded by Wright and Bailey as of Torridonian age. Kiloran Bay breaches and occupies the centre of a structural basin in this series, the shores of the bay being margined by the Staosnaig phyllites, the youngest beds of the succession. The latter are in turn margined by the Colonsay limestone and successively older members of the sedimentary sequence.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: Geology