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More than 5,400 earthquakes have struck Christchurch since the big one on September 4th, with well over a hundred (142 to be exact) in the past seven days alone. (See http://www.christchurchquakemap.co.nz/ ) When readers first broached the idea of an imminent volcanic eruption, I laughed. But then I learned that Banks Peninsula, just south of Christchurch, consists of two overlapping "extinct" volcanoes, the Lyttelton Volcano and the Akaroa Volcano. (See http://www.iceagenow.com/Is_Christchurch_headed_for_a_volcanic_eruption.htm ) Long considered dormant, scientists have not been overly concerned about these volcanoes. However, new information may change their minds. No Such Thing as a Dormant Volcano
In a fortuitous bit of timing, Science Daily published an article just
this week entitled "Until now it was thought that once a volcano's magma chamber had cooled down it remained dormant for centuries before it could be remobilized by fresh magma," says the article. However, a theoretical model developed by by Alain Burgisser of the Orléans Institute of Earth Sciences and George Bergantz of the Earth and Space Science Department in Seattle, has completely overturned this hypothesis.
Reawakening could occur "in just a few months" The new research is published in the journal Nature dated 3 March 2011. According to previous theories, when a volcano is not erupting it cools down to an extremely viscous mush until fresh magma from deep inside Earth 'reawakens' it, a process thought to occur over a period of several hundred or even thousands of years. However, according to the new model, and depending on the size of the chamber and the viscosity of the magma it contains, "a few months may be sufficient to rekindle its activity." The two researchers tested the validity of their model against both the eruption of Mount Pinatubo in the Philippines in March 1991. Twenty to eighty days
The model "predicted that 20 to 80 days were sufficient to remobilize the
underlying chamber, whereas the conventional theory gave a figure of 500 years."
See entire article:
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