Africa

Africa is the most stable continent with respect to its movement during the late plate tectonics.
The nucleus of the continents is based on the amalgamation of different cratons, which are
associated with large, deep basins. Although there has been long-standing scientific efforts towards
the structure of the crust and mantle underneath Africa, ground-based observations are still sparse in
all but a few regions. The seismological SASE array in South Africa (Carlson 1996) has helped to make
the Kaapvaal Craton one of the best-studied Cratons in the world. Outside the coverage of this array,
there are only few observations. This is due to the strong logistical challenges to conduct
measurements in many parts of Africa. Surface wave tomography is one of the methods to recover
structures in regions that are not directly covered by seismic instruments, as the information about
the velocities within the Earth is distributed along the ray path between source and receivers. Using
this technique, Fishwick (2010) constructed a seismic reference model for southern Africa from
earthquakes occuring on the mid-ocean ridges surrounding the continent and available seismic
stations. Still, the reliability of the models greatly increases in regions with seismic measurements and
thus for considerable parts of Africa this model can only be considered as a first indicator.
For magnetotelluric measurements we can obtain reliable information in the vicinity of the stations
with a region of influence roughly comparable to the depth of investigation. Compared to seismic
data, the coverage in southern Africa is significantly better thanks to the large-scale SAMTEX
experiment.
Martinec and Fullea (2015) discussed the sensitivity of the GOCE gravity model to the density
stratification of the uppermost part of the Earth's crust and demonstrated that a priori geological
knowledge of the density stratification of the sedimentary rocks that form the Congo basin can largely
be improved in both horizontal and vertical directions. Also for the Bangui magnetic anomaly to the
north of the Congo basin a mantle contribution has been proposed and we will re-evaluate these
models and ideas with the new satellite data and link the results closely to global and regional velocity
and conductivity models. In addition, the southern portion of Africa exhibits high topography for which
dynamic topography has been proposed as an origin and Africa is as well located over the LLSVP at the

core-mantle boundary, which makes it an ideal case to study the link between the deep Earth and the
surface.