Preliminary Imaging of La Palma Island's Crustal Structure, Canary Archipelago, Using Receiver Functions from a Dense Broadband Network

Following the 2021 Tajogaite eruption, in la Palma Island, Canary Archipelago, the IMAGMASEIS project was launched to deploy a dense seismic network across the island. The network comprises 37 broadband seismometers, provided by the GFZ and the University of Granada, in addition to 20 permanent stations operated by the Spanish National Geographic Institute (IGN) and the Volcanological Institute of the Canary Islands (INVOLCAN). This network ensures dense coverage of the entire island, with inter-station distances of approximately 5 km and a maximum distance between stations of 40 km.  This temporal network operated from September 2023 to October 2024.

One of the main objectives of this project is to enhance our understanding of the island's crustal structure. To achieve this, we derive P-wave receiver functions from teleseismic records and use them to construct 2D seismic profiles employing the Common Conversion Point (CCP) methodology. This approach allows us to image the Moho discontinuity across the island.

Our preliminary analysis indicates a shallow oceanic Moho in the southern part of the island, at depths of approximately 10 km, consistent with previous studies. In contrast, the northern part of the island reveals a more complex and thicker crustal structure. In this region, the accumulation of magma beneath pre-existing Moho discontinuity (magmatic underplating) may explain Moho depths reaching up to 30 km.