1,800 earthquakes hit the Portuguese volcanic island in three days

Since the beginning of the month, multiple small earthquakes have shaken Sao Jorge, causing experts to worry that the series of earthquakes might lead to a stronger one or a volcanic eruption. As of Saturday afternoon, there were 1,800 earthquakes recorded on the volcanic island, up from 1,329 earlier in the week, according to Rui Marques, head of the region’s seismo-volcanic surveillance centre. In the past year, there have been 94 earthquakes felt by the population, with magnitudes ranging between 1.7 and 3.3.

Azores consists of nine islands. Approximately 8,400 people live in Sao Jorge, one of nine municipalities. It belongs to the central group, which includes Faial and Pico, which are popular tourist destinations. These quakes, which are known as a swarm and which are causing no damage, have been recorded along the volcanic fissure of Manadas, which last erupted in 1808. ‘To be on the safe side, Sao Jorge’s municipalities will activate emergency plans,’ Marques told Antena 1 radio.

On the one hand, there is the possibility of an earthquake with a greater magnitude causing some damage. ‘Alternatively, we have the scenario of an eruption. Marques encouraged residents to remain vigilant, despite the fact that the earthquakes were tectonic in origin, which means they were caused by the movement of plates on the Earth and are not volcanic. We should not treat this as a purely tectonic crisis but as a seismic crisis that is taking place in an active volcanic system,’ Marques said.

The CIVISA established two additional seismological monitoring stations on the island and deployed a team to monitor soil gas levels, which are indicators of volcanic activity. The levels, as of now, appear to be normal, Marques said. The Civil Protection authority said on Tuesday it was coordinating with other agencies to prepare for the possibility of a major earthquake or volcanic eruption. The sudden escalation of seismic activity on the Azores is similar to the earthquake waves that preceded last year’s eruption of Cumbre Vieja, some 1,400 km to the southeast of the Azores.