The Sezione di Catania - Osservatorio Etneo (INGV) reported that eruptive activity at Etna’s summit craters during 18-24 August was characterized by lava effusion from two vents, Strombolian activity and ash emissions at SE Crater, and gas emissions at NE, Bocca Nuova, and Voragine craters. Activity was observed through webcams and by observatory staff doing daily fieldwork in the summit area. Lava effusion continued at a vent around 2,980 m elevation located along the N-S-trending fissure between Bocca Nuova and SE Crater. Lava flows were overlapping at the distal end of the flow field; the longest flow reached 2 km.

Two new vents opened on 20 August. The first vent was located at 3,100 m elevation at the base of the saddle between Bocca Nuova Crater and the Southeast Crater. Observatory staff witnessed the opening of the vent during the morning and saw spattering and lava flows that descended the W flank. The flows were 670 m long by 24 August. The second vent opened at 1340 on 20 August on the S flank of SE Crater, at 3,200 m elevation. The vent produced several branching lava flows that advanced S and SW. By 24 August the flow was 880 m long with the S branch reaching 2,980 m elevation and the SW flow reaching 2,950 m elevation. The new flows were estimated to be about 1.5 m thick.

Geological Summary. Mount Etna, towering above Catania on the island of Sicily, has one of the world's longest documented records of volcanism, dating back to 1500 BCE. Historical lava flows of basaltic composition cover much of the surface of this massive volcano, whose edifice is the highest and most voluminous in Italy. The Mongibello stratovolcano, truncated by several small calderas, was constructed during the late Pleistocene and Holocene over an older shield volcano. The most prominent morphological feature of Etna is the Valle del Bove, a 5 x 10 km caldera open to the east. Two styles of eruptive activity typically occur, sometimes simultaneously. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more summit craters. Flank vents, typically with higher effusion rates, are less frequently active and originate from fissures that open progressively downward from near the summit (usually accompanied by Strombolian eruptions at the upper end). Cinder cones are commonly constructed over the vents of lower-flank lava flows. Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank.

Source: Sezione di Catania - Osservatorio Etneo (INGV)