New insights into the crust and lithospheric mantle structure of Africa from elevation, geoid, and thermal analysis

• DOI: 10.1002/2016jb012972
• Publication Date: 2016-06-24T20:26:45Z
• Authors: Jan Globig; Manel Fernàndez; Montserrat Torne; Jaume Vergés; Alexandra Robert; Claudio Faccenna
• Keywords: Isostasy; Seismic Tomography; Elevation (ballistics); Mantle plume

Abstract We present new crust and lithosphere thickness maps of the African mainland based on integrated modeling elevation geoid data thermal analysis. The approach assumes local isostasy, steady state, linear density increase with depth in temperature‐dependent lithospheric mantle. Results are constrained by a comprehensive compilation seismic Moho consisting 551 points published tomography models relative to LAB depth. crustal map shows N‐S bimodal distribution higher values cratonic domains southern Africa (38–44 km) those beneath northern (33–39 km). most striking result is thinning (28–30 km thickness) imaged along Mesozoic West Central Rift Systems. Our model noticeable differences compared previous models. After excluding Afar plume region, where assumptions not fulfilled, our better fits available (76.3% fitting; root mean square error = 4.3 large spatial variability (90 230 km), deeper related shallower Cenozoic rifting domains, agreement Though show similar regional patterns, major found Atlas Mountains, System, intracratonic basins. effects lateral variations as well nonisostatic contribution which we estimate be ~1.8 km, also discussed.