WATERFORD GEOLOGY

From A Topographical Dictionary of Ireland, 1837

The geology of this county exhibits no great variety, nearly the whole being composed of clay-slate, sandstone, and some limestone. The elevated region between the Suir and the Blackwater, comprising the heights of the Cummeragh and of Knockmeledown, is a table land of clay-slate, partly bordered by sandstone, and sustaining isolated caps of the same rock. Its outskirts are marked by Carrick, Clonmel and Clogheen, on the north; and by Kilmacthomas, Dungarvan, and Lismore, on the south: on the north, west, and south, it is bounded by limestone.

A border of sandstone approaches close to the Suir on the south side, from the vicinity of Ardfinnan to Kilmaiden, four miles west of Waterford. The clay-slate throughout the mountain district is of a reddish brown, purpleish, or greenish grey colour; it ranges nearly uniformly north-west and south-east, and dips generally from 70 to 75 degrees to the south and south-west. Good slates for roofing are raised in the glen of Ownashad, near Lismore, and in Glen Patrick, near Clonmel. Near the junction of the streams that form the river Mahon are veins of quartz, comprising granulated lead ore; and in the same mineralogical tract, at Kilkeany, near Mountain Castle, there is a fine vein of lead ore.

The rocks to the north of Lismore are also rich in mineral veins: iron, copper, and lead ores are of frequent occurrence. Lismore Castle stands on a floetz limestone rock, which, partly separated from the clay-slate by a border of fine-grained sandstone, extends in a narrow range down the vale of the Blackwater, to the innermost recesses of Dungarvan harbour: in several places it assumes the character of marble, as at Tourin, where it is variegated with many colours; near New Affane, where it is black and white; in the parish of Whitechurch, where it is both black and grey, &c.

In the country to the south of this range, beyond the river Bricky, the clay-slate and sandstone again prevail in the same relations as to the north: near the summit of the Drum mountain the white sandstone partakes of a slaty structure, and bears fossil impressions of leaves, fern branches, &c., near which are thin seams of black shale or coal slate; but between the Drum mountain and the coast, limestone again occurs, and extends into the sea. Mineral veins, containing lead, iron, and copper ores, were formerly worked on this side of the Drum, and are said to have been very productive: at Minehead and Ardmore very valuable iron ore was procured, and converted into the finest steel: of the copper and lead mines also worked at the latter place, the ores, from fragments still found, are supposed to have been very rich.

The eastern portion of the county consists almost entirely of clay-slate, presenting a disposition of range and dip nearly approaching to that observed more westward. Limestone, however, imbedded in indurated clay-slate, is found on the sea-coast, at Lady's Cove, in the immediate vicinity of Tramore: it is of the primitive kind, and capable of receiving a very high polish, but is chiefly burned for manure. Near Annstown, farther westward, occur both conglomerate and basalt; and a range of trap rock of a columnar tendency projects into the sea. In the high land extending from Dunhill towards Waterford are occasionally found large masses of very beautiful jasper. Along the coast, the rocks are rich in metallic veins; and the elevation and abruptness of the cliffs greatly facilitate their discovery.

Lead and copper ores have been found at Annstown and Bonmahon, near which the copper mines at Knockmahon are carried on most scientifically and extensively by the Mining Company of Ireland, which has a lease of the royalties of the district: they are considered to have the most complete machinery in Ireland, and give employment to 940 persons. A lead mine, the ore of which contains a considerable portion of silver, in the parish of Ballylaneen, belongs to the same company, but has not yet been worked. In the conical hill of Cruach, in the parish of Reisk, a rich vein of lead ore, containing a large proportion of silver, was formerly worked to a great extent. On the strand of Kilmurrin, lead ore, containing a large proportion of silver, is dug from among the sand.

The south-eastern angle of the county is wholly composed of sandstone and conglomerate throughout a line of coast three leagues in extent. The sea has in some places laid bare a clear uninterrupted sheet of the rock, exposed in one plane at low water for 300 yards in length and 50 in breadth. The conglomerate of this coast bears all the marks of the detritus of a primary country: it sometimes forms a thick and apparently unstratified mass, resting on finer stratified sandstone; and sometimes it is interstratified with the latter, as well as with very fine-grained reddish-brown micaceous sandstone, which is of a very perishable nature, and in these the sea has formed spacious caverns.

Potters' clay is found in numerous places, at Dungarvan, Ringagonagh, Lismore and Whitechurch; pipe clay, at Ballyduff, near Dromana and at Ballyntaylor; ochre, at the last-named place, and in small veins in various other parts; and red bole, at Ballyduff. The sandstone is worked in numerous places for building, for grindstones, and millstones; and marl is found incumbent on the limestone.

« Waterford Agriculture | Index | Waterford Manufacturing »

County Waterford | Waterford Towns and Baronies | Waterford Topography | Waterford Agriculture | Waterford Geology | Waterford Manufacturing | Waterford Rivers | Waterford Antiquities | Waterford City


Library Ireland Facebook