Tuesday, January 04, 2011

Mt Etna Awakens With Strombian Explosions

It was an educated guess when I wrote in December:
Mount Etna is overdue for an eruption if the earlier pattern of Vulcanology is anything to go by. Preceding patterns of Etna's eruptions listed on the USGS 'Global Volcanism Program' site, reveals the last activity was in May 2008: "6-km-long lava flow; ash emissions; 13 May 2008 opening of a new eruptive fissure". The last 2 year no-activity phase was 1972-1973, after which Etna began a lengthy but gentle series of activity until May 2008:
12/1971 (CSLP 33-71)
Periodic explosions from La Voragine crater
02/1974 (CSLP 20-74)
W-flank eruption rapidly builds cone; explosions and lava flows

Erik Klemetti @ BigThink.com reported that .. Etna has also greeted the new year with some new strombolian explosions and impressive fountaining early Monday morning (1/3).

If I were a Vulcan(spock)ologist that would fascinate me... I mean, how is it that volcanoes have patterns of behaviour? What is behind this? Where do volcanoes get their timing from? What does this tell us about the Earth we live on?

The Italian National Institute of Geophysics and Volcanology reported Monday that Mount Etna has once again become active - erupting large amounts of ash and rocks. The eruption at Mount Etna is accompanied by the ejection of volcanic ‘bombs’ (large stones) with large amounts of ash in the area southeast of the crater on Monday night.

Mount Etna is Europe’s highest and most active volcano. Etna’s most powerful recorded eruption was in 1669, when explosions destroyed part of the summit and lava flows from a fissure on the volcano’s flank reached the sea and the town of Catania, more than ten miles away.

An interesting fact: In 122 BC, when an explosive eruption rained so much ash and lapilli onto the town of Catania that many of its buildings were destroyed by roof collapses, the town’s inhabitants were exempted from paying taxes to Rome for ten years. Geology.com

Is Etna long overdue for a big one?

Are the big volcanoes on Earth the prime tension joints whose activity is designed to take the stress and release it, because they are big enough and strong enough to do the job? Recently (and not unrelated), a giant solar explosion spread across an entire hemisphere of the sun's surface caused NASA to reconsider the sun's activity.

NASA Science News released: Global Eruption Rocks the Sun.
Dec. 13, 2010: On August 1, 2010, an entire hemisphere of the sun erupted. Filaments of magnetism snapped and exploded, shock waves raced across the stellar surface, billion-ton clouds of hot gas billowed into space. Astronomers knew they had witnessed something big.
It was so big, it may have shattered old ideas about solar activity.

It would have to be the same for the Earth .. I mean that the whole planet is affected by large movements in the planet's core magnetism that all at once alter the continental plates, weather streams, magma, volcanic activity (or create a decrease in activity).

We could probably better understand this observing how the outer planets of our Solar System react. Perhaps they are mirrors, to help us better understand our own world. I find it hard to understand why scientists divide local tectonic and volcanism into tiny areas unrelated to the whole and imagine that activity in one area is not related to activity elsewhere on the Earth.

I don't know why; but I have this feeling that the Earth's volcanoes have an important role to play in the restructuring of the planet and restructuring the future. Volcanoes play a much bigger long term role in altering societies than we realise. Not only on the surface of the planet (above sea level), as I am sure underwater volcanoes are just as relevant.

Lava flows from a volcano can be catastrophic for the people and the land around the base of the volcano; but as years pass and the lava cools that land becomes highly fertile. The cooling volcanic soil is rich in nutrients and is of high value to farming communities. In those first moments a volcano can destroy lives, livestock, farmland and homes - but later the process of that eruption create life and is a source of wealth for people in the future.

Volcanoes are almost Zen like, with the breath of death and life contained in one event.