Page 1 of 52 Journal of Quaternary Science 1 2 3 SPELEOGENETIC EVIDENCE FROM OGOF DRAENEN FOR 4 5 6 A PRE-DEVENSIAN GLACIATION IN THE BRECON 7 8 BEACONS, SOUTH WALES, UK 9 10 11 Andrew R. Farrant 1, Christopher J. M. Smith 2, 3 , Stephen R. Noble 4, Michael J. Simms 5, 12 2, 3 13 David A. Richards 14 15 16 1. British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK. E-mail:
[email protected] 17 2. Bristol Isotope Group (BIG), Wills Memorial Building, University of Bristol, Queen’s Road, Bristol, 18 BS8 1RJ, UK. 19 3. School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK. 4. NERC Isotope Geosciences Laboratory (NIGL), British Geological Survey, Keyworth, Nottingham, 20 NG12 5GG, UK. 21 5. Department of Geology, National Museums Northern Ireland, Cultra, Holywood, Co. Down, BT18 22 0EU, Northern Ireland. 23 24 25 Abstract 26 27 The British Isles have been affected by as many as 30 glaciations during the Quaternary. 28 29 However, the evidence for pre-Devensian glaciations in upland regions is scarce. 30 31 Understanding the extent and timing of earlier upland glaciations is essential for modelling 32 the long term evolution and sensitivity of the British Ice Sheet (BIS). Caves, being protected 33 34 from surface erosion and weathering, can preserve evidence of earlier glaciations in the form 35 36 of speleothem and sediment archives. The ~70 km long Ogof Draenen cave system in South 37 Wales, UK, contains multiple cave levels related to changes in the surface topography and 38 39 drainage during the past 0.5 Ma.