UPPER CARBONIFEROUS OR COAL-MEASURES. / / | | A series of sandstones, shales, | | | | and fire-clays, with interbedded | =Flat Coal Group.= / | | seams of coal occupying the | (Above 1000 feet.) \ | | central area of Mid-Lothian | | | | coal-field. | \ | | | |—————————| | / | | | | | | | | | | A great series of sandstones | | | | and shales with three seams of / =Roslyn Sandstone / | | marine limestone (marked here \ Group.= \ |·········| by dotted lines), With the | (About 1500 feet.) | | | exception of one or two thin seams | | |·········| it contains no coal, and serves in | | | | this way to mark off the coal- | | | | bearing beds above from the still | | | | richer coal-bearing beds below. | \ |·········| | |—————————| | / | | | | | | A group of sandstones and | =Edge Coal Group.= / | | shales similar to those at the \ (800-900 feet.) \ | | top, and like them abounding in | | | coal seams, some of which are \ | | thick and valuable. ———————————————————————————————————————————————————————————————————————— CARBONIFEROUS LIMESTONES. | | / =Roman Camp / | | A set of marine limestones | Limestones.= | | | intercalated with sandstones, \ (150-200 feet.) \ | | shales, and a few seams of coal. ———————————————————————————————————————————————————————————————————————— LOWER CARBONIFEROUS. | | / | | | | | | =Burdiehouse / | | Sandstones and shales extending | Limestone.= | |·········| to an unknown depth, often | (27 feet.) \ | | with seams of dull-grey compact / | | limestone, rarely of coal. The \ Thickness of Lower | | beds become very red towards | Carboniferous Rocks | | the base, and wholly devoid of | unknown, but | | fossils. | probably greater | | | than that of the | | \ upper. | |