Unusual eruptions

23. August 1998

At 17:26 local time, a powerful explosion, probably located at the NE Crater, occurred in the summital area of the volcano. A strong blast was heard throughout the island, and a column of ash and lapilli was shot over the craters. Incandescent bombs thrown out by the explosion fell on a vast area and in many different directions, including Vallonazzo, Labronzo, Forgia Vecchia, etc. At least another explosion followed the first one. Several fires were started in the vegetation on the upper volcano slopes (the biggest one, near Forgia Vecchia, was stopped only the following day, 24 August). It seems that no tourists were affected by the explosion. From Ginostra the emission of a big, light ash cloud is reported after the first dark column, and small lapilli fell over the village.

Worried tourists watch the volcano after the eruption. Photo Gianfranco Cincotta.	Growth of the eruption cloud. Photos Susanna Cincotta.

A first survey made by Stromboli volcano guides has shown the presence of bombs on the tourist path down to an altitude of 750 m a.m.s.l. In other directions the bombs fell as low as 500 m a.m.s.l. The explosion also caused significant morphological changes to the rim of Crater 1 towards Semaforo Labronzo. The authorities immediately blocked puhlic access to the upper part of the volcano. Prof. Franco Barberi personally visited the island for the Civil Defense.

Our seismic station has recorded the event associated with the explosion. These are the first 50 seconds: