Articles | Volume 9, issue 2
Solid Earth, 9, 457–467, 2018
Solid Earth, 9, 457–467, 2018

Research article 17 Apr 2018

Research article | 17 Apr 2018

Crustal thickness of Antarctica estimated using data from gravimetric satellites

Muriel Llubes1, Lucia Seoane1, Sean Bruinsma2, and Frédérique Rémy3 Muriel Llubes et al.
  • 1Université Paul Sabatier, OMP-GET, UM5563, CNRS/IRD/UPS, 14 Avenue Edouard Belin, 31400 Toulouse, France
  • 2CNES, Department of Terrestrial and Planetary Geodesy, 18 Avenue Edouard Belin, 31401 Toulouse CEDEX 4, France
  • 3OMP-LEGOS, UM5566, CNRS/IRD/UPS, 14 Avenue Edouard Belin, 31400 Toulouse, France

Abstract. Computing a better crustal thickness model is still a necessary improvement in Antarctica. In this remote continent where almost all the bedrock is covered by the ice sheet, seismic investigations do not reach a sufficient spatial resolution for geological and geophysical purposes. Here, we present a global map of Antarctic crustal thickness computed from space gravity observations. The DIR5 gravity field model, built from GOCE and GRACE gravimetric data, is inverted with the Parker–Oldenburg iterative algorithm. The BEDMAP products are used to estimate the gravity effect of the ice and the rocky surface. Our result is compared to crustal thickness calculated from seismological studies and the CRUST1.0 and AN1 models. Although the CRUST1.0 model shows a very good agreement with ours, its spatial resolution is larger than the one we obtain with gravimetric data. Finally, we compute a model in which the crust–mantle density contrast is adjusted to fit the Moho depth from the CRUST1.0 model. In East Antarctica, the resulting density contrast clearly shows higher values than in West Antarctica.

Short summary
We computed a global map of crustal thickness covering the entire Antarctic continent from GOCE satellite gravimetric data. We compare our result to seismological models: a fairly good agreement is shown. However, better resolution is obtained using the gravity observations than using only seismological ones. This research will help us to understand the geology of Antarctica.