The aim of this study was to gain a better geological understanding of the southern Africanudregion through the use of magnetotelluric (MT) and seismic techniques. Specifically, theudnewly collected southern African magnetotelluric experiment (SAMTEX) data are analysedudfor directionality using a tensor decomposition technique. Instead of conducting the analysisudfor given periods, as is commonly done, the data are analysed for approximate depths dueudto the variable electromagnetic penetration across the region. I also re-analyse previouslyudcollected southern African seismic experiment (SASE) data for shear wave splitting of teleseismicudevents using standard processing techniques. These analyses provide information onudthe electrical and seismic anisotropy properties of the region, which may then be related toudtectonics and geological structure. It is found that MT conductive direction results, for bothudcrustal and lithospheric mantle depths, are significantly more complex than has previouslyudbeen observed in other regions. The complexity is attributed to be due to strong effectsudof large-scale conductivity heterogeneities on the conductive directions measured. The reanalysisudof some of the SASE stations for shear wave splitting has produced near-identicaludresults to those previously measured, and I was not able to conclusively demonstrate theudpresence or absence of 2-layer anisotropy. A previously unnoticed relationship is observedudbetween thick lithosphere, and regions of well correlated seismic fast axis directions and plateudmotion directions. Combined with the observations of vertical variations in conductive directionsudof the MT results, this has led to a new model being proposed to explain the anisotropyudresults observed in the region. The model suggests both lithospheric and asthenospheric contributionsudto seismic anisotropy, with a significantly stronger anisotropic layer below thickerudlithosphere, which is proposed to be due to stronger lattice preferred orientation (LPO) ofudolivine as a result of increased flow velocity below the thicker lithospheric keel. This modeludis supported by other geoscientific observations, including the results from the lithosphericudand asthenospheric MT analysis. No strong correlation between the measured MT and seismicudanisotropy parameters is observed, likely because the electrical anisotropy is stronglyudeffected by structure, and the seismic anisotropy is predominantly a result of LPO of olivineud(in places, quite strongly vertically varying).
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