Residual topography and lithospheric structure of the Antarctic continent
Abstract
Antarctica has been the subject of considerable interest in the past few years, following the International Polar Year. The structure of its crust at a continental scale is however still known with large uncertainty. A new Moho depth map for the Antarctic continent has been recently assembled (AntMoho), merging copious information from geophysical and geological studies selected from the literature. A large volume of old and new data has been analyzed: mostly seismic experiments, as well as receiver functions and geological studies, ranging from DSS profiles acquired by Soviet Union field experiments, to recent seismic receiver function studies. AntMoho has a reference lateral resolution of 1 degree. We compare this new model to other available for the whole continent (Bassin et al., 2000; Block et al., 2009) and study the possible geodynamic consequences calculating the residual topography. Residual topography is obtained by removing the isostatic contribution of the crust from the observed topography. Long-wavelength residual topography is interpreted as dynamic response to large scale mantle convection and density contrasts. Our calculations show that significantly different inferences on lithospheric structure and mantle dynamics may result from the variance in Moho depth recorded in the different models. A better knowledge of Moho depth and, more generally, crustal structure for Antarctica at a continent scale is a goal with likely consequences for better understanding of the complex dynamic processes acting at a regional scale.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.T41B2584M
- Keywords:
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- 7205 SEISMOLOGY / Continental crust;
- 7218 SEISMOLOGY / Lithosphere;
- 8120 TECTONOPHYSICS / Dynamics of lithosphere and mantle: general;
- 9310 GEOGRAPHIC LOCATION / Antarctica