In the Introductions of two recent Quaternary field guides to the Mountains of Mourne, Northern Ireland, the caption that accompanies an image of the Cloghmore erratic boulder states that "It is thought to have been transported by Scottish ice and originated from the Firth of the Clyde". The image is credited to Conor Graham but the source of the caption is not clear (Roberson, 2016, 2019). However, no evidence in support of this assertion of Scottish provenance was provided in the field guides. If the boulder had been transported and deposited by ice emanating from Scotland, presumably during the late Devensian/Midlandian glaciation (~32-15 ka), it would have implications for the direction of ice flow from the northern sector of the Irish Sea Basin. The ice would have had to have moved either southwest across the Mountains of Mourne or southwest across the Mourne Plain, to the south of the mountains, and then west into the Carlingford trough. The purpose of this note is to argue that the boulder and adjacent erratics are likely to be of more local (Irish) derivation, rather than from Scotland, and to highlight concerns about using apparently accepting information without question.
|Number of pages||5|
|Publication status||Published - 7 Oct 2021|