Abstract
Anomalies in teleseismic arrivals at stations astride the West African Craton margin in Senegal are large and systematic for rays which have passed beneath the craton margin. Lateral variation in seismic velocity structure beneath the margin persists to several hundred kilometres depth. The major relative delay time and slowness–azimuth anomalies fit a simple model of a steep boundary in the mantle aligned with the major gravity anomaly associated with the craton margin. The mantle beneath the Mauritanide orogenic belt has lower P-velocity than the adjacent craton between ∼80 and 220 km, but higher average velocity both above and below that depth range.
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Briden, J., Whitcombe, D., Stuart, G. et al. Depth of geological contrast across the West African craton margin. Nature 292, 123–128 (1981). https://doi.org/10.1038/292123a0
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DOI: https://doi.org/10.1038/292123a0
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