We drilled through 509 m of firn and ice at Prudhoe Dome , northwest Greenland to obtain sub-ice material yielding direct evidence for the response of the northwestern Greenland Ice Sheet to Holocene warmth. We collected ~3 m of sediment above ~4.4 m of bedrock between 6-6-2023 and 6-7-2023 using the ASIG drill operated by the United States National Science Foundation Ice Drilling Program. We measured luminescence signals from K-feldspars (150-200 micron fraction) at select depths within the sediment column at the University of Texas at Arlington Luminescence Laboratory using single-grain post-infrared infrared stimulated luminescence measured at 225℃ (p-IR IRSL225) measured on a Risø DA-20 luminescence reader. Our dataset contains estimates of equivalent dose (De) from a Minimum Age-3 Model (MAM-3) assuming a 15% overdispersion, the necessary DRAC (Dose Rate Age Calculator; Durcan et al., 2015) input information to calculate dose rates, and our calculated ages. We sent aliquots (1-10 g) of material from four depth intervals, 0-7.5 cm, 8.0–11.2 cm, 81.5–88.0 cm, and 173.3–177.8 cm, for XRF and ICP-MS measurements of radionuclides at SGS Canada (0-7.5 cm) or the Washington State University Peter Hooper GeoAnalytical Lab (8.0–11.2 cm, 81.5–88.0 cm, and 173.3–177.8 cm). We measured water content by measuring the mass of samples before melting and again after melting and after drying sediments in a 50 ℃ oven overnight. Our data record the last time sediments under Prudhoe Dome were exposed to sunlight, necessitating that Prudhoe Dome was absent from our site.References:Durcan, J. A., King, G. E., and Duller, G. A. T.: DRAC: Dose Rate and Age Calculator for trapped charge dating, Quaternary Geochronology, 28, 54-61, https://doi.org/10.1016/j.quageo.2015.03.012, 2015.).
Dose Rate and Age calculator (DRAC) input: https://www.aber.ac.uk/en/dges/research/quaternary/luminescence-research-laboratory/dose-rate-calculator/