Edad de los domos sálicos de la isla de La Gomera

Abstract

The new radiometric data from felsic domes on La Gomera allow to separate two different felsic both intrusive and extrusive episodes on the island. The early one, upper Miocene in age, includes the domes on the eastern sector of the island as well as the radial and the conical dikes cropping out on the north. Within this early episode of felsic magmatism, the domes on the eastern sector and the so called eastern radial dike-swarm seem to be contemporaneous and slightly older (8.6-7.9 Ma) than the western radialdike swarm and the con e-sheet complex, a structure which also includes some related domes (7.5-6.4 Ma). A later felsic episode, lower Pliocene in age (4.5-3.9 Ma),includes all the rest of existent domes on La Gomera which are less alkaline and peralkaline than the older ones.