Was the cirque glaciation of Wales time-transgressive, or not?

Abstract

The lowest glacial cirques in Wales are in the South Wales Coalfield and in western mid-Wales: the highest are in the northeast and on the highest mountains. Floor altitudes show great local variability, but in general rise to the northeast in most of Wales and northward in southern Wales, as does the former glaciation level (from 470-710 m a.s.l.). The pattern is similar for reconstructed Younger Dryas glaciers, which occupied the higher and even some of the lower cirques. If cirque development had spread to lower areas as the ice sheet built up, cirques would be expected in peripheral areas such as the northeast and southwest, away from the main ice-sheet sources. This is not seen and there is no clear evidence of time-transgressive cirque glaciation. Cirques relate to phases of glaciation with an ELA a little below that in the Younger Dryas.