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Resumen:
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Six new isotopic age determinations were established in volcanic rocks of Tenerife. These data belong to different units of the main volcanic edifices and the results allow us to get a more accurate knowledge of the eruptive history of the island. One of these ages corresponds to a trachyandesitic flow of the Upper Unit of the Anaga Old Edifice (Old Basaltic Series) and the result, 3,38 ±0,19 Ma matches with the age interval established by previous authors for this unit (3,70 - 3,28 Ma). Three ages belong to units of the Cañadas Edifice and the results are 1,59 ± 0,19 Ma, 2,94 ± 0,15 Ma and 4,0 ± 0,2 Ma. This shows that the felsic volcanic activity started in the very early stages of the Cañadas Edifice evolution and it shows also that there are a partial overlap with the youngest episodes of the Old Tenerife Edifices. The age determination on a phonolitic plug that intrudes on basaltic flows of the Dorsal Edifice gives a result of 1,16 ± 0,09 Ma. The last age data of this work belongs to a mafic phonolite flow of a peripherial volcano (Taco Mountain). The result, 0,55 ± 0,06 Ma reinforces the evidence of felsic-intermediate volcanic activity in several peripherial volcanoes contemporary with the Cañadas Edifice lifespan.
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