Fausto Ferraccioli1, Jörg Ebbing2
1Nerc/British Antarctic Survey, Cambridge, United Kingdom, 2University of Kiel, Kiel, Germany
Geothermal heat flux is a key and yet poorly understood boundary condition that can affect past, present and future ice sheet dynamics via e.g. its influence on subglacial hydrology, and sediment and basal ice deformation, and it also important to determine in the quest for retrieving the oldest ice via new deep ice core drilling. In addition to its relevance for glaciology and paleo ice sheet studies GHF is important also as both a tracer and an influence on the tectonic and magmatic evolution of the Antarctic continent.
Studies to date of Antarctic geothermal heat flux comprise e.g. estimates derived from seismology, satellite and airborne magnetics, radar-derived estimates of basal reflectivity and basal water, direct measurements via drilling and rock samples, erratics and modelling approaches. The results of these studies vary significantly both in terms of spatial distribution, spatial resolution, magnitudes and uncertainties.
The recent availability of continental scale compilations of airborne gravity, new satellite gravity gradient data and notably a new magnetic anomaly compilation (ADMAP 2.0) that includes almost 3.5 Ml line km of data provide the means to start tackling the issues surrounding GHF estimation in additional ways too. As part of a new European Space Agency initiative ADMAP 2.0+, an extension to the 3D Earth project of ESA, which will be launched in Feb. 2018 we plan to image and model the variability in crustal and lithospheric architecture of Antarctica in unprecedented detail and also assess its implications for the spatial variability of GHF. Here we will present the approaches that the project intends to develop further. A new basement province map for a large part of East Antarctica will be compared and contrasted with the currently available estimates of GHF and several key areas where new thermal models are required will be discussed.