Nuevos datos de magnetotelúrica (MT) en Tenerife

Resumo

Thirteen broad band (BBMT) and three long period (LMT) magnetotelluric soundings were carried out in Montaña Blanca within Las Cañadas caldera in Tenerife. The periods range from 0.004 s to 500 s for the BBMT data and from 10 s to 20000 s for the LMT data. The electrical and magnetic fields were recorded in NS and EW directions as well as in the vertical direction for the magnetic field. Dimensionality analysis indicated a predominant direction of the electrical resistivity and a 2D inversion of the data was carried out along two profiles. In this preliminary study only periods lower than 20 s were used in order to avoid the sea effect. The inverse models reveal the presence of a conductive layer at 400-500 m depth associated with a main aquifer. Within this conductive layer the models show zones of highest conductivity, which are associated with hydrothermal alteration. The combination with previous existing MT sites allows identifying the continuity of these zones of hydrothermal alteration out the Las Cañadas caldera.