The dataset contains 12 new Be-10 cosmogenic nuclide surface exposure ages. The samples were collected from a scoria cone 1.5 km west of Mt. Murphy an exposed volcanic edifice adjacent to Pope Glacier in the Amundsen Sea Embayment, Antarctica. Samples of erratic cobbles which showed evidence of transport by ice were collected over the 2015-2016 AmuNdsen Sea Embayment Exposure Dating (ANISEED) Field Season, prepared at the CosmIC laboratory, Imperial College London and measured for Be-10 at the Australian Nuclear Science and Technology Organisation. Beryllium-10 concentrations were measured by Accelerated Mass Spectrometry (AMS). Samples were measured to determine timing of deglaciation of two rock outcrops to better constrain the ice sheet lowering history of Pope Glacier during the Holocene. Study forms part of the wider International Thwaites Glacier Collaboration Project (ITGC). Samples were collected by Dr. Joanne Johnson and Dr. Stephen Roberts (British Antarctic Survey), supported by field assistants Alistair Docherty and Iain Rudkin. Sample preparation for 10Be measurement was carried out by Jonathan Adams - PhD candidate affiliated with British Antarctic Survey/ Imperial College London under the supervision of Dr. Dylan Rood - Imperial College London. AMS measurements of Beryllium-10 concentrations were performed by Dr. Klaus Wilcken - Australia''s Nuclear Science and Technology Organisation (ANSTO). National Science Foundation (NSF: Grant OPP-1738989) and Natural Environment Research Council (NERC: Grants NE/S006710/1, NE/S006753/1 and NE/K012088/1 and studentship to JRA). ITGC Contribution No. ITGC.

This dataset comprises 52 cosmogenic 10Be surface exposure ages and associated analytical data from quartz-bearing rocks from Mount Murphy and surrounding nunataks in Marie Byrd Land, Antarctica. The samples - glacial erratics and bedrock - were collected between 2006 and 2016 by Joanne Johnson, Stephen Roberts and James Smith (British Antarctic Survey), in order to determine timing and duration of ice sheet thinning in the Amundsen Sea sector of the West Antarctic Ice Sheet, specifically thinning of Pope Glacier. The data are published and interpreted in the following paper: Johnson, J.S., Roberts, S.J., Rood, D.H., Pollard, D., Schaefer, J.M., Whitehouse, P.L., Ireland, L.C., Lamp, J.L., in review. Deglaciation of Pope Glacier implies widespread early Holocene ice sheet thinning in the Amundsen Sea sector of Antarctica. Earth & Planetary Science Letters. doi: xxxxx This data forms part of the ANiSEED project (''Amundsen Sea Embayment Exposure Dating''), funded by the Natural Environment Research Council (grants NE/K012088/1 and NE/K011278/1).

This dataset consists of measurements of cosmogenic Be-10 and Al-26 in quartz for a set of cobbles collected from a moraine proximal to Mount Murphy, a nunatak located between Pope and Thwaites glaciers, West Antarctica. The cobbles were collected during the 2015-2016 Antarctic field season. The dataset includes cosmogenic nuclide (Be-10 and Al-26) surface exposure ages and all field (location, elevation, shielding, thickness) and analytical laboratory (quartz, beryllium and aluminium carrier masses, Be-10/Be-9 and Al-26/Al-27 ratios) data for field samples and procedural blanks required to calculate the ages. Funding source: Natural Environment Research Council (NERC: Grants NE/S006710/1 (JSJ), NE/K012088/1 (JSJ), NE/S006753/1 (DHR), NE/K011278/1 (DHR)). Australian Nuclear Science and Technology Organisation (ANSTO) Centre for Accelerator Science award AP12872 (DHR) through the National Collaborative Research Infrastructure Strategy (NCRIS).