• Old Southeast Crater (last active 7 May 2007)
  • New Southeast Crater, source of 13 paroxysmal eruptive episodes between January and early September 2011
  • the breached eastern to southeastern portion of the New Southeast Crater cone
  • the rocky "spine", or pinnacle, formed during the 8 September 2011 paroxysmal eruptive episode
  • the site of short-lived explosive activity (emission of dark brown ash and white vapor) at a later stage of the 8 September 2011 paroxysmal eruptive episode, and possibly the source of a small lava flow
  • the site of the first ash emission on the north flank of the New Southeast Crater cone during the 8 September 2011 paroxysmal eruptive episode
  • eruptive fissure of the 2008-2009 flank eruption

The twin Southeast Craters and that strange rock needle

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As devoted followers of my photostream will have noted, there has been quite a lot of change to the shape of Etna's summit area this year. This is mostly the growth of a large new cone made of loose volcanic (pyroclastic) material, which is piling up around the New Southeast Crater - not long ago, it was still called "pit crater" - and had become more than 150 m tall before the latest two paroxysmal episodes on 29 August and 8 September 2011. The southern and northern rims of the crater have grown further during these latest two episodes, but the eastern and southeastern flanks of the cone have suffered from more destructive, mass wasting processes, involving landslides, opening of fissures, and entrainment of sections of the cone by lava flows.

The most peculiar effect of the latest paroxysm on 8 September is the formation of a rather conspicuous pinnacle of rock, or a "needle", on the lower southeast flank of the new cone. This thing is widely visible especially from northeast and north, even from Taormina, and there are already a few rather spectacular close-up views of it on Flickr (which I will link to in the comments below). Its height was initially about 25-30 m, though since then chunks of it have repeatedly fallen off, reducing both its height and width. This structure, which consists of an uplifted and rotated portion of the cone's flank (presumably entrained by lava flows and rotated when encountering an obstacle), composed of stratified scoriae, is certainly rather weak and might disintegrate even before the next paroxysmal episode will definitely cancel any trace of it.

This view was taken from the "Mareneve" road on Etna's northeast flank on the morning of 10 September; it shows the "old" (sulfur-coated) Southeast Crater cone at right, the "new" Southeast Crater cone in the center, and the rock needle at left. Furthermore, near the left margin of the image, a reddish-brown patch corresponds to the zone where lava was emitted and sporadic explosions took place during the 8 September paroxysm, presumably when new vents opened there. A similar, though much smaller brown spot lies a bit further upslope, just a little below the yellow sulfur patch, and this is the first of these vents that opened early during the paroxysm of 8 September.

Etna continues to surprise us, and this makes it more and more fascinating and intriguing.

piccola*020511, Mirko Chessari, and 4 other people added this photo to their favorites.

  1. etnaboris 32 months ago | reply

    A spectacular view of the disrupted southeast flank of the New Southeast Crater and the rock spine taken by Rianetna on 9 September 2011

    Another wonderful shot by EtnaWalk, also on 9 September 2011

    ... and a much closer zoom on that thing, by Marco Restivo, 9 September 2011

  2. tedesco57 32 months ago | reply

    There's a ot going on on Etna

  3. piccola*020511 32 months ago | reply

    è veramente spettacolare la sua metamorfosi ... !!

  4. Etna Walk 32 months ago | reply

    Quasi la stessa posizione e con gli stessi protagonisti! :D


  5. tightorbit 32 months ago | reply

    tightorbit (5 seconds ago | edit | delete)

    Prosit for the very detailed account of the "openings" from where phenomena are occurring on Etna. For the record, a few minutes ago (08.15h local) Etna was fuming from two vents but I could not say which of those shown on the photo these were. Also, there was a 2.1 mag. earthquake 10 km deep on the western rim of the volcano at 03.15h local and the ESVO seismic tracking has been quite perturbed for this time of in-between paroxysms. On the basis of the 6.5 and 10 day time-lapse estimate , we may be set for another event between Thursday and Sunday, if not earlier.
    More, on the needle shaped object. Watching closely Rianetna's third photo above, this object is accompanied by a downslope flow of material to the right which makes one think of a solid mass of material impeding a falling blob from taking level position on the ground. The blob then solidified in mid-air due to a sudden change of temperature from scalding hot to mountain-top cold and possibly prevailing winds. In that case, more than a needle shaped object I would rather style it a massive cold drop!

  6. etnaboris 32 months ago | reply

    the two fuming vents that you refer to are the Northeast Crater and the Bocca Nuova, neither of which is visible in the view in this photo (they're beyond the right margin of the view) :-D

    The drop-shaped "spine" is clearly a section of the disrupted cone, because it consists of neatly layered scoriae and bombs, the same material that also makes up the remaining crater rim. Only thing is that the layers are not showing the same inclination as those in the still intact crater rim, but they point vertically toward the sky, evidence that this thing has been somehow rotated into its current position. In any case, it's one rather remarkable creation of Etna, and unfortunately it will not last for long because it's already crumbling and falling to pieces and what will remain until the next paroxysm will most likely be overwhelmed and cancelled by that event :-(

    a verità è :-D
    Già si vede come fra le due foto, la forma della "spina" è cambiata, come essenzialmente questo coso si sta disintegrando ...

  7. piero giuffrida | jebel 32 months ago | reply

    gran reportage post parossismo ... tanti occhi che vedono e fotografano i cambiamenti morfologici del SEC ....grazie a tutti ... :)

  8. tightorbit 32 months ago | reply

    @ etna walk

    Si puo vedere di piu` questo cambiamento se si guarda alla foto pubblicata dal INGV-CT nell'Aggiornamento Etna del 8 Settembre. Li si vede molto chiaramente nella seconda foto della spina che c'e`una struttura ben definita con due altre spine laterali in altitudine uguale, benche` un rigonfiamento uguale alla base, che dimostrano una simmetria eccezionale. Sopra le due spine laterali ci sono anche due altri prelevamenti verticali corti su ambedue lati, mentre il lato destro gia` si disintegra per vedere piu` somiglianze. Per me tutto questo indica un gocciolone di magma con i relativi spruzzi simmetrici che si formano quando un liquido batte una superficie dura che non lo assorbe interamente. E` anche da vedere se le scoriae e le bombe provengono dalla massa stessa o se erano spostati ed incollati alla massa durante il suo impatto duro con il suolo.

  9. plasticisnotfantastic 32 months ago | reply

    woow! such a great view! must be very impresive i'm sure!

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