Authorities in the Spanish Canary Island of La Palma have cautioned that an increase in earthquake activity in the coming days or weeks can trigger a volcanic eruption.
In the Cumbre Vieja national park, around the Teneguia volcano in the far south of the island, the National Geographic Institute has reported 4,222 tremors in an “earthquake swarm”. This earthquake swarm triggers volcano alert in Spain’s La Palma.
The Canary Islands regional government issued a yellow alert for an eruption on Tuesday. The quakes intensified and moved closer to the surface, the second of four levels of concern.
On Thursday, it said there was no obvious evidence of an impending eruption. But warned that the situation may quickly deteriorate.
“More intense earthquakes are expected in the coming days,” it said in a statement.
The Volcanic Institute of the Canaries said on Thursday that more than 11 million cubic meters (388 million cubic feet) of lava has leaked into Cumbre Vieja in recent days. Thereby, expanding the peak by roughly 6 millimeters.
The Canary Islands rise abruptly from the Atlantic around 100 kilometers west of southern Morocco. They are also home to some of Spain’s most active and well-known volcanoes. They include Teide in Tenerife and Timanfaya in Lanzarote.
Teneguia last erupted on the surface in 1971, making it Spain’s last active volcano. But a volcano off the coast of El Hierro erupted underwater in 2011.