An earthquake measuring 1.9 on the Richter scale was felt early Tuesday on the island of Terceira in the Azores, the Azores Center for Seismic Volcanic Information and Observation (CIVISA) said.
According to CIVISA, the earthquake occurred at 9:23 a.m. local time (10:23 a.m. Lisbon time) and had an epicenter about five kilometers northeast (northeast) of Santa Barbara.
“According to the information available today, an earthquake with maximum intensity III (Modified Mercalli Scale) was felt in Santa Barbara (municipality of Angra do Heroísmo),” the note said.
The Center for Seismovolcanic Information and Observation explains that this event is part of the “ongoing seismovolcanic crisis on the island of Terceira since June 2022.”
On the Richter scale, earthquakes are classified by magnitude into micro (less than 2.0), very small (2.0-2.9), small (3.0-3.9), weak (4.0-4.9), moderate (5.0-5.9), strong (6.0-6.9), large (7.0-7.9), important (8.0-8.9), exceptional (9.0- 9.9) and extreme (when more than 10).
The Modified Mercalli Scale measures “degree of intensity and corresponding description.”
At intensity III, considered weak, the shock is felt inside the house and hanging objects sway, feeling “vibrations similar to those caused by heavy vehicles passing by,” IPMA says on its website.
At intensity IV, considered moderate, parked cars shake, windows, doors, and utensils shake, “glasses and utensils rattle or clank,” and walls or woodwork may creak.