Etna update, 25 July 2011

Etna erupting on the morning of 25 July 2011, generating a plume of ash that is blown eastward by the wind. At the source of the eruptive plume, an incandescent lava fountain can be seen, which is rising from the active crater on the east flank of the Southeast Crater cone; the summit of the volcano is covered by a lenticular cloud associated with strong wind. View is from south-southeast. Photo taken by Agatino Reitano and published with kind permission of the author

Seventh paroxysmal episode from Etna's Southeast Crater

On the evening of 24 July 2011, vigorous Strombolian activity started within the crater located on the east flank of the Southeast Crater cone; this activity showed a gradual increase through the night, and culminated the next morning between 0230 and 0630 GMT (= local time -2) in a new paroxysmal eruptive episode. A lava flow started to travel through the breach left in the eastern crater rim by the previous lava overflows at about 0130; between 0230 and 0300 the Strombolian activity gradually passed into a pulsating lava fountain, accompanied by increasingly voluminous ash emission. During this time interval, the lava flow split into several parallel branches, following the same path as the lava flows emitted during the previous paroxysms, reaching the base of the steep western slope of the Valle del Bove near Monte Centenari. The lava fountain reached its maximum heights, fluctuating around 250-300 m, between 0400 and 0500 GMT, with a few jets rising up to 350 m high. The plume of gas and ash was blown eastward by strong wind, leading to ash falls in the area between the villages of Fornazzo and Milo on the mountain slope, and the Ionian coast near Riposto. As in the case of the preceding paroxysm (19 July), the final phase of this episode consisted of a prolonged series of violent explosions, which generated loud detonations heard over a wide area in the eastern and southeastern sectors of the volcano.

This has been the seventh paroxysm from the same crater since the beginning of this year (the previous episodes had occurred on 12-13 January, 18 February, 10 Aprio, 12 May, 9 July, and 19 July); the interval between this and the previous episode was 6 days, and thus the shortest interval since the onset of the current series of paroxysms.