Evidencias de mezcla de magmas en el Edificio volcánicosubvolcánico de Betancuria (Fuerteventura, Islas Canarias)

Abstract

The volcanic subvolcanic Betancuria edifice belongs to the upper part of subaerial Miocene volcanic serie. It is made of evolved basalts (mainly trachybasalts), polimictic welded tuff and trachyandesytetrachysyenite annular dikes. These rock-succesions are genetically interelated by a process of basaltic and tra chy tic magma mixing. Mingling evidences are represented by polimictic banded welded luff, composite dikes and emulsion facies trachyandesitic rocks. Chemical mixing (or hibridation) is noted in homogeneous trachyandesitic facies by the «reequilibrated» mixed phenocristal population. Well defined geochemical linear trends in variation diagrams is a strong evidence of the hibridate origin of the trachyandesite rocks