The 22 July 1998 eruption of the Voragine

Many of the following photos were kindly provided by Sandro Privitera (22-23 July 1998) and Carmelo Monaco (20 August 1998), both of Dipartimento di Scienze Geologiche of Catania University. Other photos of 22 July 1998 are courtesy of photographs credited in the captions. Photos are by Boris Behncke unless otherwise noted; thanks again to Carmelo Monaco for lending me his camera during my round trip to Bocca Nuova and SE Crater on 20 August 1998.

	The view from Catania (southern flank) Left: Huge mushroom-shaped eruption column rising above Etna's summit at about 1835 h (local time). The view is from south and was taken by Sandro Privitera from the balcony of his home in Catania-Ognina. Top right: Top of the eruption column, seen from same location. Photo by Sandro Privitera. Bottom right: View from the same location of Etna's summit with continuing, though diminished, ash emission from the Voragine. The umbrella region of the huge eruption column is still visible in the upper right portion of the photo. Photo by Sandro Privitera.
	The view from Bronte (western flank) These three photos were taken by a photographer working for "Ottica Mary" of Maria Messina, Bronte, at intervals ranging from a few minutes to about ten minutes. Top left: Shortly after the beginning of the eruption. A part of the spreading top of the eruption column can be seen at the top of the image. Bottom left: The umbrella-shaped cloud at the top of the eruption column is extending northeastwards while ash is falling to the south of the eruption column. Right: Further growth of the eruption column. Dense fallout is occurring on the southern, and to a lesser degree, on the northern and eastern sides of the eruption column.
	The view from Piano Provenzana (northern flank) This series was taken by a person working in one of the tourist shops on Piano Provenzana, near the hotel "Le Betulle". The images were taken with an amateur camera and the negatives have suffered from scratches and dirt (see the yellow dots in the first photo), but nonetheless render a good idea of the event. Note that these thumbnails are only small sections of the original photos which are shown completely in the enlargements. Times when the photos were taken are not known, but it is assumed that about 15-20 minutes passed from the first to the last photo. Photo 1: This photo shows a dense gas plume rising from the Voragine; the plume contains no ash and may form at the top of a lava fountain. The steep cone visible at the summit of Etna (at the base of the plume) is NE Crater which stands in straight line with the Voragine as viewed from Piano Provenzana. Clouds at right base of the eruption plume are weather clouds. Photo 2: The plume rising from the Voragine is getting denser and is mixing with ash. Photo 3: As the intensity of the eruption increases, more ash is rising with the eruption column, and the column is getting broader as heavy fallout is occurring in the summit area. NE Crater with its vapor plume is still visible. Photo 4: The paroxysmal phase of the eruption is now in full swing, and the eruption column is heavily charged with ash. Note the dark plume extending at the left base of the main eruption column, possibly caused by an inclined fountain to the eastern side of the Voragine (this is probably not a pyroclastic flow). NE Crater is no longer visible. Photos 5, 6 and 7: The eruption increases in vigor, and the entire summit area is concealed by falling pyroclastics. Photo 8: The eruption column is pitch black, and the summit area is subjected to heavy fallout. Photo 9: A panoramic view of the eruption column developing a mushroom shape. Height of the column above the summit is at least 7 km. A dense pall of fallout extends to the southeast (left of the eruption column). One of the mountain guides working on the northern side of Etna was near the summit of Etna when the eruption began. First he was curious to see what was going on at the Voragine and tried to get closer. As the activity became ever stronger, he felt "real fear, more than at any other time in many years of working on Etna" and left the area. Fortunately, there was no one at the Voragine at the time of the initial explosion which occurred without any warning - otherwise the eruption would certainly have killed somebody. The point from which the best view of the Voragine can be obtained, the southern rim of the NE Crater, was buried under up to ten meters of agglutinated pyroclastics.
	Two spectacular views of the huge mushroom-shaped plume as seen from the island of Salina (Aeolian Islands), more than 100 km to the north. The photos were kindly submitted by Paul Oord and contrast-enhanced to make the plume more apparent.
	Photos at left: Top: Street in Milo, on the E flank of Etna, the morning after the great eruption: ash is lying everywhere, having a thickness of more than 1 centimeter. Photo by Sandro Privitera. Middle: Residents of Milo clearing streets and squares from the freshly fallen ash, on the morning of 23 July 1998. Photo by Sandro Privitera. Bottom: Ash-covered car in a village on the eastern flank of Etna, 23 July 1998. Photo by Sandro Privitera. Photos at right: Top: Press photo of the Bocca Nuova a few days after the 22 July 1998 eruption, showing the crater floor covered with steaming black lava that has cascaded into the Bocca Nuova from the Voragine. This photo was published in the journal "La Sicilia" several weeks after the eruption but clearly was taken shortly after the eruption. Bottom: SE Crater in Strombolian activity, with two lava rivers flowing down its northeastern side, on the evening of 24 July 1998. This activity ended a few days later, after more than 20 months of uninterrupted eruptions from the crater; activity resumed on 15 September 1998. Photo scanned from "La Sicilia" of 25 July 1998.
	Photos from a summit visit, 20 August 1998 Photos at left: Top: View of SE Crater looking down from the southeastern rim of the main summit cone. Much of the area is mantled with a thick scoria deposit of the 22 July 1998 eruption. Activity at the SE Crater ceased in late July 1998, after about 20 months of uninterrupted Strombolian eruptions and lava effusion. Middle: Gaping fractures on the eastern side of the former summit crater, some 100 m southeast of the Voragine. These fractures formed during the 22 July 1998 eruption but apparently were not the site of eruptive activity. By the time this photo was taken there were no emissions from the fractures, but vivid incandescence was visible within them during the days after the eruption. Bottom: Intracrater cone of SE Crater viewed from the southwestern crater rim. Lava and pyroclastics have filled the pre-1996 crater depression to the rim. Photos at right: Top: View from the western rim of Bocca Nuova of the lowered "diaframma", the wall between Bocca Nuova (in the foreground) and Voragine. The formerly craggy outline of the crest of the "diaframma" has been smoothed by a vigorous lava flow cascading from the vent behind it into the Bocca Nuova during the 22 July 1998 eruption. Middle: Both vent areas of the Bocca Nuova are visible in this image, taken from the western rim of the crater. TheNW cone with at least 4 vents is at left while the mainly collapsed SE cone is visible in the right background. The lava flow that cascaded into the Bocca Nuova during the Voragine eruption of 22 July 1998 is visible as a chaotic, fractured terrain between the two vent areas and in the lower right corner of the image. Bottom: Lava flow (the craggy, light gray-brown streak in the middle of the photo) erupted from Voragine on 22 July 1998 on the NW side of main summit cone. This flow, the first from the area of the former Central Crater (which now hosts both Voragine and Bocca Nuova) since 1964, stopped after crossing the vehicle track that connects the southern and northern flanks of Etna. In the background the destroyed southern flank of the NE Crater cone, carried away with the flow as it streamed out of the Voragine.
	Left: The huge scar carved out of the southern flank of the NE Crater cone during the lava outflow from the Voragine on 22 July 1998, photographed on 20 August 1998. The height of the collapsed zone is several tens of meters. Right: Zoom of Boris Behncke standing on the southern rim of NE Crater, with vigorous explosive activity from the two main vents within the Voragine on 20 August 1998. Ash is exploding from the central vent while huge bombs are being ejected from the southwestern vent, near the "diaframma". Photo was taken by Carmelo Monaco.

Copyright © Boris Behncke, "Italy's Volcanoes: The Cradle of Volcanology"