LISBON—Authorities in Portugal’s Azores archipelago have been placed on alert after nearly 90 small earthquakes hit the mid-Atlantic volcanic island of Sao Jorge in a little over 24 hours, although there have been no reports of damage.
Sao Jorge’s Urzelina volcano last erupted in 1808 and the Azores Civil Protection authority has requested an evaluation by experts from the region’s volcanic surveillance center.
