A multi-domain lithospheric model of East Antarctica

The geology of East Antarctica is poorly constrained and covered by ice which can be several kilometers thick, however, these hidden and inaccessible rocks are of major interest in interdisciplinary studies linking the solid Earth and cryosphere. Subglacial geothermal heat flux is an important parameter for ice sheet models and depends on heat production within the crust, but also the deep geothermal gradient that is defined by the lithospheric structure.

Seismic tomography studies derive lithosphere thickness and structure, but the resolution is relatively low, and the smoothed models don't reflect the amalgamation of lithospheric terranes that formed the continent. We combine geophysical constraints from seismic properties and potential field data, with geological knowledge from the sparse Antarctic outcrops and from Gondwanan neighbours in a plate reconstruction framework. We use Bayesian inference to suggest the most probable boundaries by using a multivariate prior. The boundaries form a segmentation of the Antarctic lithosphere and can be weighted with probabilistic significance and location.

The result is presented as a first draft of a multi-domain tessellated terrane map of the East Antarctic lithosphere. We believe that this approach will be useful in estimating both basal lithosphere and crustal contributions to heat flux, and is a robust stepping stone towards more refined models.