Edades 39Ar/40Ar de los depósitos de Roques de García (Las Cañadas, Tenerife)

Abstract

During the evolution of the Las Cañadas volcanic edifice, debris avalanches were very significant destructive events. The Roques de Garcia unit was generated by such an event. 39Ar/40Ar dating has been carried out on different rock types related to this deposit. 1.70-1.40 Ma ages were measured on volcanic matérial involved in the avalanche deposit, 0.43 Ma on a phonolitic dyke cutting this formation. These results bracket the age of the debris avalanche emplacement which could mark either the transition between Cañadas ll-Cañadas III (1.4-1.1 Ma) or Cañadas Illa-Cañadas lllb (0.6-0.7 Ma) volcanic phases