The Ballachulish Fold near the Head of Loch Creran (Argyllshire)

Abstract

The main features of the tectonics of the Loch Creran district have already been delineated in a paper dealing with a more extended region, and published in 1910 by the Geological Society of London. The results of this earlier work, brought up to date, are epitomized in the map (p. 322), which will serve as an index of the relations of the district to neighbouring portions of Argyllshire and Inverness-shire. The original mapping of lower Glen Creran was carried out by Mr. H. Kynaston and the late Mr. J. S. Grant Wilson. Before preparing the paper just cited, I visited the district on two or three occasions, once accompanying Mr. C. T. Clough, and at another time Mr. H. B. Maufe. Various alterations in the mapping were made as a result of these traverses, and it was found that the more essential structural features were readily determinable in the light of evidence furnished by the country to the north-east. At the same time, it was apparent from the first that anything like detailed knowledge could only be attained as a result of systematic re-examination, involving a considerable expenditure of time. A favourable opportunity for further work arose officially during the past season, when observations were made which seem worthy of record as an illustration of the complexity locally recognizable in the Highland Schists. Two main difficulties are encountered in the field: there are many slides (fold-faults), so many, in fact, that the original stratigraphical sequence has to be accepted from