Contact-Alteration near New Galloway

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Abstract
§ 1. I ntroduction . The eastern end of the northern edge of the Cairnsmore-of-Fleet granite-mass follows the crest of the Knocknairling Hill to the west of New Galloway for about half a mile. The metamorphism of the rocks of this hill has been briefly alluded to in the “Memoir Explanatory of Sheet 9 of the Geological Survey of Scotland,” p. 22, but is so extreme as to deserve a fuller description. There are many exposures on the hill-side; and the Knocknairling Burn gives a good section across the series at a distance of about half a mile from the granite. It is a pity that the beds cannot be traced farther from the granite, especially as there is some doubt as to the series to which they belong. The Cairnsmore-of-Fleet granite is some twelve miles by six in extent, with its greatest elongation in the direction of the prevalent strike of the Silurians. The Survey has given the name of “Queensberry Grits” to the series into which it has been intruded, but suggests that the altered rocks of Knocknairling Hill consist of the underlying Moffat shales and Upper Ardwells, brought up here during the folding of the district. The Upper Ardwells, where unaltered, to the east of the granite, consist of rapidly alternating flags, shales, and greywackés.The flags and shales are often sandy and micaceous. The greywackés do not seem to differ from those of the overlying Queensberry Grits. § 2. T he K nocknairling -B urn S ection . In working up the Knocknairling Burn from

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