Residents on Spain’s La Palma island are bracing for the possibility of bigger earthquakes more than five weeks after a volcano erupted.

Seismologists said a 4.6 magnitude earthquake shook the island a day after they recorded a 4.9 magnitude quake that was the strongest so far of the hundreds that have occurred under La Palma since the Cumbre Vieja volcano’s September 19 eruption.

So far, the earthquakes have either been small enough or far enough under La Palma to do no harm, other than adding to the anxiety of the island residents.

The Tuesday earthquake was felt up to 60 miles away on three other segments of the Canary Islands, an archipelago off northwest Africa.

“The scientific committee has been warning for more than a week that we could see earthquakes, given their recent depth of around 12 kilometres (7.4 miles) and their magnitude, that reach a magnitude of 6 (on the Richter scale),” María Jose Blanco, director of Spain’s National Geographic Institute on the Canary Islands, told Spanish national broadcaster RTVE.

Flows of molten rock from the Cumbre Vieja volcano itself have caused the evacuations of about 7,500 people and destroyed more than 2,000 buildings, mostly homes.

The rivers of lava cover over 900 hectares (2,200 acres) of mostly farmland, while one major flow is extending the island into the Atlantic as it cools.

No deaths have resulted from the eruption. Other than in an area on the island’s western side, life continues as normal for La Palma’s 85,000 residents except for having to clean up volcanic ash.

The last eruption on the island, in 1971, lasted 24 days. Its longest, in 1949, lasted 47 days. The current activity is on day 39 and shows no signs of stopping.

“We saw the worst-case scenario in the 1949 eruption, when a second volcano mouth opened up and cut off the southern part of the island, which had to be supplied by boat,” volcano scientist Vicente Soler said.

“That is highly improbable, although not impossible, today.”