IV. On a Section of Carboniferous Strata, near Giffen Station, Ayrshire

Abstract

In the first cutting of the Kilbirnie branch of the Caledonian railway, a short distance from Giffen station, a small section of Carboniferous rocks is exposed, their position being in connection with the horizon of the Highfield limestone. This section would perhaps not be worthy of special notice but for the occurrence in it of a bed of sandstone which, from its close proximity to a fault, has become bent in a remarkable manner. The total length of the section is about 320 feet, and the strata are seen in this short distance to occupy a syncline, an anticline, and half an anticline, the latter feature being brought about by a fault. Two faults are also to be seen, though there are probably three, one being hid by the pier of the railway bridge. Commencing at the east end of the section, we first see a bed of sandy shale, slightly micaceous, with non-septarian ironstone nodules, a few being of the slickensided variety. This bed dips 10° towards the west. Above it there are 2 feet 6 inches of fireclay, slightly micaceous, and containing rootlets, and where the mica is abundant the fireclay is of a harder texture than it is elsewhere. Over this is 1 foot 4 inches of coal, which is a mixture of splint and free coal, and the jointings are either filled with carbonate of lime or bisulphide of iron. Above the coal is 1 foot 4 inches of black shale; and above the shale lies This 250-word extract was created in the absence of an abstract