9 March 2007: Pyroclastic Flows on Sciara del Fuoco
After a short pause during the effusive eruption on 8 March, Stromboli "woke up" again next morning and reached a climax of activity during the afternoon of 9 March: A new vent opened at 500m.a.s.l., in the middle of Sciara del Fuoco, causing a new lava flow which produced remarkable pyroclastic flows towards the sea. All times are local (GMT + 1hr). Focal length of the lenses used on a digicam is given (to be multiplied by 1.5 to obtain the equivalent focal length on 24x36 film).
8 March, 18h, f=50mm. Fishermen in a boat below Sciara are surprised: «Has the eruption already come to its end?».
9 March, 15h10m-15h30m, f=16mm. Small steam puffs in the middle of the Sciara slope (left of center in lower photo) mark the onset of a new flow.
9 March, 15h20m, f=135mm. Eruptions of ash from the summit craters stopped at mid afternoon, while the lava flows reach their highest rate.
9 March, 16h, f=300mm. Since mid morning, the lava flow fed by the vent at 420m.a.s.l. is also quickly advancing towards the lava delta in the sea.
9 March, 16h, f=300mm. The lava front of the new flow fed by the vent at 500m.a.s.l. appears in the middle of Sciara del Fuoco.
9 March, 16h, f=135mm. Unusual white steam is emitted by the lava front: is a new fissure opening towards the sea?
9 March, 17h, f=50mm. Suddenly, the lava front becomes unstable, and plunges towards the sea, quickly generating a pyroclastic flow.
9 March, 17h, f=135mm. Other pyroclastic flows reach the coast, then stop, after which dust clouds rise: note the incadescent bombs just below the flow head.
9 March, 17h30m, f=300mm. Zoom on the front of another pyroclastic flow: note incandescent blocks in the avalanche of hot ash and rocks.
9 March, 17h30m, f=300mm. This photo was taken only 3 seconds after the previous one, and thus shows the speed of the pyroclastic flow.
9 March, 18h, f=135mm. Meanwhile, the other lava flow fed by the vent at 420m.a.s.l. is approaching the sea, again scaring the seagulls.
9 March, 18h, f=50mm. Wide angle view of the lava flow in the foreground and a pyroclastic flow further back.
9 March, 18h, f=16mm. During twilight the lava front stabilizes, and the pyroclastic flows stop, but many red blocks continue to fall into the sea.
9 March, 18h, f=50mm. Lava flow in the foreground and individual, rolling incandescent blocks in the background.
9 March, 18h, f=50mm. Many red blocks plunge into the sea. Some surf for many meters over the water surface before they disappear.
9 March, 18h, f=50mm. Twilight scenes at Sciara del Fuoco.
|Copyright: M. Fulle.|