![]() ![]() ![]() Later studies included northeastern seamounts and inferred a wider NE-SW-oriented fixed-plume track 4 beginning near Essaouira Seamount (68 Ma) and ending around El Hierro and La Palma (<4 Ma 14). 1) and the assumptions that Canarian island-seamounts grow fast and that their subaerial ages were representative of the onset of magma generation and mantle upwelling at any given site. Original fixed-plume models 5 were based on the E-W alignment and apparent age progression of the Canary Islands from Lanzarote-Fuerteventura (15–23 Ma 12) to El Hierro (<1.1 Ma 13) ( Fig. Plausible models for the formation of scattered seamount chains like the CISP include (a) deep mantle upwelling through fixed mantle plumes 5, (b) shallow passive mantle upwelling beneath mid-ocean ridges 11 and (c) shallow mantle convection from continental lithosphere flanks 3. Primitive CISP basalts are derived from decompression melting of upwelling mantle that includes deep (HIMU-type), depleted (DMM-type) and enriched (EM-type) mantle components 7, 8, 9 and erupt after limited interaction with altered MORB crust and Cenozoic sediments 10. It represents the easiest hotspot track to find in the northern part of the African plate 2, but its location is difficult to explain and its origin is controversial 3, 4, 5, 6. The Canary Island Seamount Province (CISP) comprises more than 100 seamounts, isolated volcanic structures on the seafloor ranging from small (1000 m) and mid-sized explosive (<700 m water depth) to ocean islands 1. ![]()
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