VII. The Carboniferous Limestones of Scotland, with their Coals

Abstract

The productive Coal-measures of Scotland are practically confined to a belt about thirty miles wide, stretching across the Central Lowlands from the Firth of Clyde in a north-easterly direction to the Firth of Forth. On the north-western boundary of this belt they are occasionally found lying more or less conformably on older strata, but are generally cut off by a series of upthrow faults, which run nearly parallel with the Lennox and Ochil Hills. These hills are largely made up of great sheets of andesite of Calciferous Sandstone age, interspersed, especially in the western district, with numerous volcanic necks of the same age—necks which now form prominent features of the landscape, such as Dumbarton Rock, Dumbuck, Dumgoyn, and Dungoil. The south-western boundary is formed by a remarkable line of faulting which has thrown up the Silurian rocks of Kirkcudbright-shire, and those of the Leadhills and of the Moorfoot and Lammermuir ranges. At many points this fault exhibits a vertical displacement of at least 10,000 to 12,000 feet. Although the coal-fields within those boundaries are now cut up by denudation into a number of separate basins, there can be little doubt that in Carboniferous times they formed one continuous series, probably extending for some distance northward, and overlapping the Old Red Sandstone of the marginal Highlands. The Carboniferous series as developed in this belt is sub-divided as follows:— 1. Coal-measures:— 2. Millstone Grit or This 250-word extract was created in the absence of an abstract