Deep crustal structure of the Walvis Ridge at the junction with the Namibian coast
The Walvis Ridge is believed to be caused by a long-living hotspot, which started to erupt with the opening of the South Atlantic. The ridge in combination with the large igneous provinces (Etendeka and Parana) in South America and Namibia is today considered to be a classical model for hotspot driven continental break-up. To unravel details on how the crust and mantle was modified by such a major thermal event, a large-scale geophysical experiment was conducted in 2011 off northern Namibia. Here, we report on the results of an active experiment perpendicular to the coast of Namibia and along the crest of the Walvis Ridge. In total, the land-sea profile with a length of 730 km consists of 28 ocean bottom stations and 50 land stations, which recorded dense airguns shots and up to 8 dynamite shots fired on the Namibian mainland. This profile concentrates on how much the continent-transition zone was affected by the eruption of the ridge, and how its crustal composition varies away from the coast, where it initially formed. The first raytracing results of the combined land-sea will be introduced.