An earthquake was recorded at 12:25 local time (13:25 in Lisbon) with a magnitude of 2.9 on the Richter scale and an epicenter approximately 4 kilometers south-southwest of Altares on Terceira Island, as reported by CIVISA.
The earthquake was felt with a maximum intensity of IV/V on the Modified Mercalli Scale in Altares, Serreta, Raminho (Angra do Heroísmo municipality), and Biscoitos (Praia da Vitória municipality), CIVISA stated.
It was also felt with intensity IV in Santa Bárbara, Doze Ribeiras, Cinco Ribeiras, Terra Chã (Angra do Heroísmo municipality), and Agualva (Praia da Vitória municipality).
Additionally, the earthquake was felt with intensity III in Quatro Ribeiras (Praia da Vitória municipality) and São Bento (Angra do Heroísmo municipality), indicating it is part of the ongoing seismic-volcanic crisis on Terceira Island since June 2022.
On the Richter scale, earthquakes are classified according to their magnitude as micro (under 2.0), very minor (2.0-2.9), minor (3.0-3.9), light (4.0-4.9), moderate (5.0-5.9), strong (6.0-6.9), major (7.0-7.9), great (8.0-8.9), extraordinary (9.0-9.9), and extreme (over 10).
The Modified Mercalli Scale measures the “degrees of intensity and respective description.”
With an intensity of III, the tremor is considered weak, felt indoors, with hanging objects swinging and a “vibration similar to the passage of heavy vehicles,” according to the IPMA.
