Determination of current geoid trends related to deep Earth processes in the South Atlantic region

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We propose to link inferences of vertical motion in the South Atlantic region over a wide range of time scales, from geologic to geodetic, the latter represented by trend analyses of non-tidal, temporal variations in the gravity field derived from ultra-precise GRACE models. The southern part of Africa, in particular, is uniquely suited for this analysis, being a region with some of the most active mantle related dynamic uplift world-wide, with little contamination from hydrologic variability or other processes.The Institute for Astronomical and Physical Geodesy (IAPG) of TU München and the Geophysics Section of Ludwig-Maximilians-University (GS-LMU) are well positioned for this project, as IAPG has been working on satellite concepts for the high resolution modeling of the gravity field for many decades, and GS-LMU has pioneered high resolution global mantle circulation models capable of inferring past mantle flow and structure through sophisticated fluid inverse theory based on the adjoint method.Key questions we wish to address include:1) Can solid Earth related signals be separated in gravity solutions?2) Over which time periods may one rely on a linear interpolation of solid Earth related gravity trends?3) Is there ongoing vertical motion in the region and how does it relate to Cenozoic uplift pulses that have been inferred for the region from geologic observations?The use of the most sophisticated gravity processing techniques, combined with powerful, high resolution mantle circulation to represent non-linear convection signals will help us to distinguish end-member hypotheses on the effect that mantle convection may have in shaping the regional tectonic evolution, namely a dominance of quasi-steady, lower-mantle related flow or, alternatively, a prominence of pulsating, semi-episodic upper mantle flow.