Figure 4

No proper age progression in the CISP.

Oldest ages of seamounts (black) and islands (grey) versus distance from Tropic Seamount along a SW-NE transect. Dotted line indicates average vector of the African Plate during the past 100 m.y. Seamount distribution should be aligned parallel to this vector (youngest in the SW, oldest in the NE) if derived from a fixed plume. Naive linear regression attempts yield poor solutions for the seamount data set (dashed line, R² = 0.20) and data set including subaerial island data (solid line, R² = 0.13), indicating a scattered age distribution and lack of a significant and systematic age progression. A = Amanay Smt., EH = El Hierro, LP = La Palma, LG = La Gomera, T = Tenerife, GC = Gran Canaria, F = Fuerteventura, S = Selvagen, L = Lanzarote (for additional age data sources see Fig. 1).