Strombolian fingerprint unveiled from multiresolution analysis of geophysical observations during the 2021 eruption at Cumbre Vieja, La Palma, Canary Islands.

Abstract

We studied the deformation pattern across the Canary Islands derived from daily GNSS time series analysis spanning the period from 2017 to the present. From the GNSS velocity field, through a triangular segmentation approach, a 2D map of the infinitesimal deformation field across the archipelago was reconstructed. This study updates our previous one for the period 2011 to 2017, which revealed E-W and NE-SW orientation patterns influenced by the regional strain field, and also suggested that the extensional and compressional regimes in the region could influence the different episodes of volcanism in the Canary Islands. Our main interest was to characterize the deformation pattern in the youngest and westernmost islands of the archipelago where the most recent episodes of volcanism took place the 2011-2012 submarine eruption in El Hierro and the 2021 subaerial eruption in La Palma. In this study, special attention was paid to the area between the islands of Tenerife and Gran Canaria, an area of intense seismic activity, where several seismic swarms have been occurred since 2018.