Part 2: The paroxysm on 16 February 2000

Start of the paroxysm

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SEC seen from Torre del Filosofo on 16 February, around noon. The fracture through the cone that had been created by the previous paroxysms is well visible. 


The start of the paroxysm is marked by increased steaming (left +´middle), occasional ash emission and strombolian explosions (middle) and the opening of a small lava-fountaining vent on the fissure below the central crater (right). 

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The explosions quickly increase in size and a lava tongue begins to flow down from the lower vent.

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Two lava fountains develop. At the top, gas-rich magma explodes and produces dark, ash-loaded clouds; at the vent below, more degassed magma escapes in a lower fountain and produces mainly white steam. Finally, the lava flow relieves the rest of magmatic gasses (blue-colored, mainly sulphur dioxide).

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Zoom to the lava fountain at the lower vent and the lava flow issuing from it.

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After just 10 minutes, the fountain has reached about 200-300 m height ! 
Right: some large bombs are thrown very far against the wind and a second fracture is opened right of the main fracture in the lower half of the the cone.

The fountain at its maximum





To the left, an oblique jet is seen that is directed against the strong wind. 
2nd left: a third vent near the base of the cone has opened on the fissure (lowest lava fountain). At least 3 fountains are now on this side of the cone. The fracrure is almost completely open and the cone split into two parts. 
Also on the right photo, jets of pressurized gas escaping the fountain and expelling bombs to the left are visible.

The dying fountain

Towards the end of the paroxysm, the fountain becomes richer in ash. Wide-angular shots showing the dying fountain now consisting of several pulses, bombs ejected into all directions and the dark, ash-loaded cloud. The lava flow has reached the base of the cone.  

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Left: ash-fall below the eruption cloud. 
Middle+right: the eruption fades quickly and ends with few spectacular ash-emissions; the pressure in the vent sinks below the point to cause violent explosions and the magma has reached a stable level close to the base of the cone from where it continues flowing out.

After the paroxysm


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After the end of the paroxysm, the second fracture in the lower part of the cone that opened during the eruption is now well visible. 30 minutes later, a new effusive vent opens at the base of the cone about 50 m E of the main fissure and a small lava flow escapes. This flow ends after some hours.

The still advancing lava front.
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Lava meets ash-covered snow... Ca. 150 cm thick section of snow and ash layers from the Torre del Filosofo. Thick white snow below is from December-January. The thin ash layers above are from paroxysmal episodes of SEC before 14 February. The thick discordant ash layer is from eruption on 14 February. No ash from 15 and 16 February fell on this area. The upper snow layer is from 17-20 February. Photo taken on 21 February.