A detailed radiostratigraphic data set for the central East Antarctic Plateau spanning from the Holocene to the mid-Pleistocene

Abstract

Abstract. We present an ice-penetrating radar data set which consists of 26 internal reflecting horizons (IRHs) that cover the entire Dome C area of the East Antarctic plateau, the most extensive to date in the region. This data set uses radar surveys collected over the space of 10 years, starting with an airborne international collaboration in 2008 to explore the region, up to the detailed ground-based surveys in support of the Beyond EPICA – Oldest Ice (BE-OI) European Consortium. Through direct correlation with the EPICA-DC ice core, we date 19 IRHs that span the past four glacial cycles, from 10 ka, beginning of the Holocene, to over 350 ka, ranging from 10 % to 83 % of the ice thickness at the EPICA-DC ice core site. We indirectly date and provide stratigraphic information for seven older IRHs using a 1D ice flow inverse model, going back to an estimated 700 ka. Depth and age uncertainties are quantified for all IRHs and provided as part of the data set. The IRH data set presented in this study is available at the US Antarctic Program Data Center (USAP-DC) (https://doi.org/10.15784/601411, Cavitte et al., 2020) and represents a contribution to the SCAR AntArchitecture action group (AntArchitecture, 2017).

Spatial characterization of near-surface structure and meltwater runoff conditions across the Devon Ice Cap from dual-frequency radar reflectivity

“…The radar return from the surface is influenced to a depth that is equal to the vertical/range resolution, which we can also refer to as the near-surface depth z 0 . The range resolution, and thus z 0 , is calculated as (Cavitte et al, 2021)…”

“…For MCoRDS3, k = 1.53 as a result of the 20 % Tukey timedomain window and Hanning frequency-domain window applied when performing pulse compression (CReSIS, 2016). For HiCARS2/MARFA, we adopt a factor of k = 1.515, as the ratio of the 100 ns compressed pulse width used in practice (Cavitte et al, 2021) to the theoretical 66 ns obtained from the 15 MHz bandwidth. ε eff of the near-surface is derived from the relative permittivity (ε) of the individual components of a multi-component heterogeneous medium.…”

Stagnant ice and age modelling in the Dome C region, Antarctica

“…The Oldest Ice candidate A (OIA) survey was conducted in January 2016 by the University of Texas at Austin Institute for Geophysics (UTIG), the Australian Antarctic Division (AAD) and the French Polar Institute Paul-Émile Victor (IPEV) as part of the ICECAP project (International Collaborative Exploration of the Cryosphere through Airborne Profiling, Cavitte et al, 2016). Radar data were collected with the High Capability Airborne Radar Sounder (HiCARS) 1 and 2, operating over frequency range 52.5-67.5 MHz (Cavitte et al, 2021), and were processed and published in Young et al (2017) and Cavitte et al (2020Cavitte et al ( , 2021. These data cover an area around 100 × 100 km 2 over LDC and Dome C. Cavitte et al (2021) traced 26 IRHs, and 19 of those were dated by linking them to the EDC site using a different transect which passes closer to EDC than the HiCARS transect (Table 3 of Cavitte et al, 2021, provides IRH ages and uncertainties).…”

Spatial characterization of near-surface structure and meltwater runoff conditions across Devon Ice Cap from dual-frequency radar reflectivity

“…The surface radar return is limited to a depth that is equal to the vertical/range resolution, which we can also refer to as the near-surface depth 𝑧 " . The range resolution, and thus 𝑧 " , is calculated as (Cavitte et al, 2021)…”

“…Hanning frequency-domain window applied when performing pulse compression (CReSIS, 2016). For HiCARS/MARFA, we adopt a factor of 𝑘 = 1.515, as the ratio of the 100 ns compressed pulse width used in practice (Cavitte et al, 2021) to the theoretical 66 ns obtained from the 15 MHz bandwidth. The effective permittivity of the near-surface is defined as a single permittivity derived from the permittivity of the individual components of a multi-component heterogeneous medium (Sihvola, 1999).…”