The last glaciers in the Aran and Arenig Mountains, North Wales

• Main Author: Hughes, P.D.
• Format: Other/Unknown Material
• Language: English
• Published: 2000
• Subjects: Ice Sheet
• Online Access: https://research.manchester.ac.uk/en/publications/3f6a68c4-3ee9-418a-8d0f-0c2707680007; https://pure.manchester.ac.uk/ws/files/141689659/Hughes_2000.pdf; https://www.qpg.geog.cam.ac.uk/graduate/mphil/9900.html

Geomorphological evidence for four former local glaciers has been mapped in the Aran and Arenig Mountains, North Wales. Pollen stratigraphic analysis of infilled lake sediments has enabled an age of the former glaciers to be deduced. Outside of the former glacier limits at Ffridd-y-Fawnog (grid ref. SH 866457) a full suite of Lateglacial and Flandrian deposits exist whilst inside of the former glacier limits at Cwm Gylchedd (grid ref. SH 866457) only Flandrian deposits exist. This implies a Loch Lomond Stadial age of the glacier at Cwm Gylchedd and, by analogy, at the three other glaciers mapped in this study. This finding is also supported by periglacial contrasts between the insides and outsides of the glacier limits. Reconstruction of the four glaciers illustrates a mean ELA of c.504 metres. Variation in ELA between the four glaciers can be primarily attributed to precipitation differences and not variations in local controlling factors. From the reconstructed ELAs and the combination of precipitation and snowblow input in deriving total accumulation, by analogy with Norwegian glaciers, a mean sea-level July temperature was calculated at 8.4 C ± 0.4 C. Also, if the Loch Lomond Stadial is assumed to represent the early stages of ice-sheet build up, then the Arenig Mountains are likely to have been an important centre for earlier Devensian ice-sheet build up. If you would like to view a copy of this dissertation please contact the author: [e-mail]