Ambient Noise Tomography studies for geothermal exploration in the Canary Islands

Abstract

Ambient Noise Tomography is a geophysical exploration technique that has proven to be highly efficient for studies at different scales and for multiple purposes, such as geothermal exploration. In this article, we introduce this technique by reviewing its various steps. Additionally, we present some examples of applications from studies conducted in the Canary Islands (sp ecifically in Tenerife, Gran Canaria, and La Palma) for geothermal exploration purposes.The study realized in Gran Canaria reveals a series of low-velocity zones in the southern and eastern parts of the island, which could be linked to convective cells. In Tenerife, a low-velocity zone has been observed, potentially associated with a superficial clay cap that could facilitate the ascent of gases to the surface. Finally, the study carried out in La Palma highlights the existence of two low-velocity zones in the southern part of the island, possibly related to hydrothermally altered clay zones, indicating a circulation of hydrothermal fluids.