The stratotype section of the Tullyard Conglomerate Member is located in both banks of the narrow, deeply incised east-flowing stream located east of the Tullyard Road (H3011 7640). The best section occurs in the south bank of the gully although the full thickness of about 4m, of the conglomerate can only be estimated by reference to additional outcrops in the waterfall, a few metres to the west.
The trace of the outcrop of the conglomerate westwards from the stratotype is simplified by the occurrence, in thin drift overlying bedrock, of abundant white, and rarely pink, quartz pebbles. This is particularly so in Killoan Townland, several hundred metres west of the stratotype, where numerous exposures, and abundant quartz pebbles in the drift, allow the member to be mapped very accurately.
The conglomerate is probably not more than 4m, or at most 5m, thick and is matrix to clast supported. The clast content consists almost exclusively of white or very rarely pink vein quartz, with occasional pebbles of reworked calcareous sandstone. Clast size very rarely exceeds 0.05-0.06m and almost 80% of the grains are smaller than 5mm. Of the remaining 20%, all but a small proportion of pebbles are less than 1.5cm in diameter. The pebbles, even down to the small grains, are well rounded and have clearly been subjected to considerable reworking and sorting in a wave agitated marine environment.
