Trough

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1990s: John-arranges in addition, The Position and volume of the lava-fields

Is it love, is it obsession? It is a bit of both, grants to John Murray , who this Year celebrates the 50-Year -old on the Etna.

The British professor heads to Sicily in the summer for the measurement of the changing curves of the famous volcano.

"I just never tired to see it; the eruptions are spectacular," he says.

family, friends and former assistants, will gather this weekend to celebrate his life's work, at a party in Nicolosi, the "gate" of the city to the mountain.

"We will show some pictures and a few memories to share," he told Bbc News .

John Murray today: "for heaven's sake, it is not As If this is a job,"

John also refers to his latest findings.

The new one is a bit different, but, because, in a sense, summarize the results, everything he has done, on the volcano in The Last half-century.

But in order to understand, what he learned, you need to know a little of the nature of the Open University-scientists are working.

He is a surveyor at heart, and since 1975, he is made carefully, which is exactly the same thing each Year - to measure heights at various points on The Summit .

It's behavior by tracking the changing shape of the Etna, which you can get insights into the "engine" that drives its eruptive.

John made his first visit to Etna in 1969 and fell in love with the mountain

Today, you might think this is a job for specialists-GPS-instruments; and it is true, the satellites are now lying to a significant part of the volcano's toolkit. But John also keeps faith with the traditional technique of leveling.

2000: John to continue with The Techniques that he always uses

you have seen this method practiced on many a Construction Site .

A person holding a staff while the other is some distance from the vertical ruler looks through a small telescope. Moving in tandem through a sequence of points, The Team created a series of height of the markers relative to a known baseline or date. Done correctly, it mm long precision.

Every summer, John and his assistants lead to the leveling of 3,100 m, in the vicinity of The Top of Mount Etna , up to 1,300 meters.

"I don't know anyone else who does this now; and I think, maybe it was not Worth It . But in The Last couple of years, it was very satisfying, because the pieces have begun in the Puzzle to fall into place," he said.

So, what's he seen? John's latest paper waned in detail how a section of The Summit of Mount Etna has almost 4m in the course of the 43 years he's been leveling.

The area of subsidence extends in a North-South Trough (what geologists call a graben), turn East at the Northern end. To be moved over the same period, the country on both sides of the subsiding Trough the walls of the trench, if you will - has, in addition to More Than 8m.

- 1970S : The frequent eruptions are spectacular

John only The Levelling says " procedure found had this feature. Ashfall and frequent lava flows make it very difficult for the radar satellite, for example, to anchor your Vision On a ground target and make consistent measurements.

"This function has been almost certainly caused by a combination of sliding-slope of Mount Etna in the direction of The Sea , () on, and radially outward gravitational spreading of the building," explains John.

"For me, The Most interesting thing is that it suggests a self-perpetuating eruptive mechanisms, which has continued for hundreds and probably thousands of years in The Past and will continue to in the foreseeable future. "

John is Looking Forward to the reunion with many of his former assistants at the Nicolosi-party. They were all his students, and he is extremely proud that so many went on to forge a successful career in the Geosciences.

As for his future, he always wants to return to the Mount Etna , Year for Year , for "the next 300 years at least," he jokes. "I'm going to continue doing it for as long as I can. For heaven's sake, it is not As If , that's a job. "

Jonathan. Amos-INTERNET@bbc. co. uk or follow Jon on Twitter :

volcanoes, earth science, sicily

Source of news: bbc.com