Historical Eruptions of the Azores - Submarine eruption of 1902, between the islands of São Jorge and Terceira

May 7, 2021

This submarine eruption occurred during the night of May 7 to 8, 1902, in the southwest of Terceira Island, on an elongated and deep submarine bank located in the alignment of the São Jorge crest, between 150 and 450 metres deep. With no visible manifestations on the surface and no record of seismic activity, this eruption was only detected because it damaged the underwater telegraph cable between Prainha do Norte (Pico) and Angra do Heroísmo (Terceira).
During the repair of the submarine cable, during the first week of June of the same year, it was found burned, with the molten metal segment and, still, with ashes clinging.

Image: Historical eruptions of Terceira Island | Author: Centre for Volcanology and Geological Risk Assessment - CVARG // ivar.azores.gov.pt