Subduction zones are places where two plates, usually an oceanic plate and a continental plate, collide. In this case, the oceanic plate subducts, or submerges under the continental plate forming a deep ocean trench just offshore. In a process called flux melting, water released from the subducting plate lowers the melting temperature of the overlying mantle wedge, creating magma. This magma tends to be very viscous due to its high silica content, so it often does not reach the surface but cools at depth. When it does reach the surface, a volcano is formed. Typical examples of this kind of volcano are Mount Etna and the volcanoes in the Pacific Ring of Fire.
Ann
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 8:18 am
by BDanielMayfield
Ann wrote:Watch one effect of the Earth's plate tectonics at work.
Subduction zones are places where two plates, usually an oceanic plate and a continental plate, collide. In this case, the oceanic plate subducts, or submerges under the continental plate forming a deep ocean trench just offshore. In a process called flux melting, water released from the subducting plate lowers the melting temperature of the overlying mantle wedge, creating magma. This magma tends to be very viscous due to its high silica content, so it often does not reach the surface but cools at depth. When it does reach the surface, a volcano is formed. Typical examples of this kind of volcano are Mount Etna and the volcanoes in the Pacific Ring of Fire.
Ann
Weren't the Alps across Southern Europe also caused by the northward drift of the African Plate? Africa is not moving near as fast as India is, causing the Himalaya and numerous other ranges in Asia, but is the complete subduction of the Mediterranean basin expected in time?
Bruce
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 8:50 am
by heehaw
I've flown from Rome to Sicily many times ... and seen Etna once! Always hidden by clouds, in my own experience.
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 12:45 pm
by Ann
In the summer of 1965, my family went to Italy for three weeks. We visited Rome and Pompeii, and I have a fuzzy memory that suggests we went on a bus trip up a road along Mount Etna. I seem to remember that the bus stopped not too far from the caldera - or maybe, close to a smaller caldera? - and my brave brother happily went up to the rim to have a look. I respectfully stayed a few steps behind, and never actually looked down into the threatening maw. I seem to remember that the volcano was smoking and spreading a sulfurous smell.
Have I imagined it all? Not the trip to Italy, which was real enough, but the bus trip to the top of Mount Etna? Possibly.
Does anyone else remember Italian bus tours bringing tourists to the top of Mount Etna in the mid-sixties?
Ann
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 1:17 pm
by neufer
Ann wrote:
In the summer of 1965, my family went to Italy for three weeks. We visited Rome and Pompeii, and I have a fuzzy memory that suggests we went on a bus trip up a road along Mount Etna. I seem to remember that the bus stopped not too far from the caldera - or maybe, close to a smaller caldera? - and my brave brother happily went up to the rim to have a look. I respectfully stayed a few steps behind, and never actually looked down into the threatening maw. I seem to remember that the volcano was smoking and spreading a sulfurous smell.
Have I imagined it all? Not the trip to Italy, which was real enough, but the bus trip to the top of Mount Etna? Possibly.
Does anyone else remember Italian bus tours bringing tourists to the top of Mount Etna in the mid-sixties?
<<Etna is one of Sicily's main tourist attractions, with thousands of visitors every year. The most common route is through the road leading to Sapienza Refuge ski area, lying at the south of the crater at elevation of 1910 m. From the Refuge, a cableway runs uphill to an elevation of 2500 m, from where the crater area at 2920 m is accessible. Stage 9 of the 2011 Giro d'Italia finished at the Sapienza Refuge. Alberto Contador initially took the win, but he was later disqualified and the stage win passed onto Jose Rujano. Stage 4 of the 2017 Giro d'Italia will also finish at Sapienza, the other ski resort is Etna Nord-Linguaglossa.>>
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 1:27 pm
by Ann
neufer wrote:
Ann wrote:
In the summer of 1965, my family went to Italy for three weeks. We visited Rome and Pompeii, and I have a fuzzy memory that suggests we went on a bus trip up a road along Mount Etna. I seem to remember that the bus stopped not too far from the caldera - or maybe, close to a smaller caldera? - and my brave brother happily went up to the rim to have a look. I respectfully stayed a few steps behind, and never actually looked down into the threatening maw. I seem to remember that the volcano was smoking and spreading a sulfurous smell.
Have I imagined it all? Not the trip to Italy, which was real enough, but the bus trip to the top of Mount Etna? Possibly.
Does anyone else remember Italian bus tours bringing tourists to the top of Mount Etna in the mid-sixties?
<<Etna is one of Sicily's main tourist attractions, with thousands of visitors every year. The most common route is through the road leading to Sapienza Refuge ski area, lying at the south of the crater at elevation of 1910 m. From the Refuge, a cableway runs uphill to an elevation of 2500 m, from where the crater area at 2920 m is accessible. Stage 9 of the 2011 Giro d'Italia finished at the Sapienza Refuge. Alberto Contador initially took the win, but he was later disqualified and the stage win passed onto Jose Rujano. Stage 4 of the 2017 Giro d'Italia will also finish at Sapienza, the other ski resort is Etna Nord-Linguaglossa.>>
Well then, I doubt that we made it all the way to the top of Mount Etna. The cableway sounds like something my parents would have been keen on, but would we have walked, or climbed, an additional 400 meters straight up to get to a threatening caldera?
Ann
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 9:53 pm
by BDanielMayfield
Ann wrote:
neufer wrote:
Ann wrote:
In the summer of 1965, my family went to Italy for three weeks. We visited Rome and Pompeii, and I have a fuzzy memory that suggests we went on a bus trip up a road along Mount Etna. I seem to remember that the bus stopped not too far from the caldera - or maybe, close to a smaller caldera? - and my brave brother happily went up to the rim to have a look. I respectfully stayed a few steps behind, and never actually looked down into the threatening maw. I seem to remember that the volcano was smoking and spreading a sulfurous smell.
Have I imagined it all? Not the trip to Italy, which was real enough, but the bus trip to the top of Mount Etna? Possibly.
Well then, I doubt that we made it all the way to the top of Mount Etna. The cableway sounds like something my parents would have been keen on, but would we have walked, or climbed, an additional 400 meters straight up to get to a threatening caldera?
Ann
Sounds like it may have Mt Vesuvius you climbed, the one that wiped out Pompeii.
Bruce
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 9:55 pm
by neufer
Ann wrote:
Well then, I doubt that we made it all the way to the top of Mount Etna. The cableway sounds like something my parents would have been keen on, but would we have walked, or climbed, an additional 400 meters straight up to get to a threatening caldera?
<<The area around Vesuvius was officially declared a national park on June 5, 1995. The summit of Vesuvius is open to visitors and there is a small network of paths around the volcano that are maintained by the park authorities on weekends. There is access by road to within 200 metres of the summit (measured vertically), but thereafter access is on foot only. There is a spiral walkway around the volcano from the road to the crater.
The first funicular cable car on Mount Vesuvius opened in 1880. It was later destroyed by the March 1944 eruption. "Funiculì, Funiculà", a famous Neapolitan language song with lyrics by journalist Peppino Turco set to music by composer Luigi Denza, commemorates its opening.>>
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Wed Apr 26, 2017 10:44 pm
by Ann
BDanielMayfield wrote:
Ann wrote:
neufer wrote:
Sounds like it may have Mt Vesuvius you climbed, the one that wiped out Pompeii.
<<"Funiculì, Funiculà" is a famous Neapolitan song composed in 1880 by Luigi Denza to lyrics by Peppino Turco. It was Turco who prompted Denza to compose it, perhaps as a joke, to commemorate the opening of the first funicular on Mount Vesuvius in that year. Six years after "Funiculì, Funiculà" was written, the German composer Richard Strauss heard the song while on a tour of Italy. Thinking that it was a traditional Neapolitan folk song, he incorporated it into his Aus Italien tone poem. Denza filed a lawsuit against Strauss and won; Strauss was forced to pay him a royalty fee. The Russian composer Nikolai Rimsky-Korsakov also mistook "Funiculì, Funiculà" for a traditional folk song and used it in his 1907 "Neapolitanskaya pesenka" (Neapolitan Song). Modernist composer Arnold Schoenberg arranged a version for ensemble in 1921 which was used in an episode of the TV sitcom Seinfeld.>>
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Thu Apr 27, 2017 1:15 pm
by Ann
Okay - my brother, with his photographic memory, has just written to me and told me that we did indeed go to the top of Mount Etna. "There was a guide with us who kept smoking, and then he blew some smoke down a hole in the volcano (not the caldera, I think), and then the volcano retorted by spitting out a big puff of smoke into our faces!"
That's what my brother just told me!
Ann
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Thu Apr 27, 2017 2:59 pm
by rstevenson
And what exactly was it your brother was smoking?
Rob
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Fri Apr 28, 2017 4:56 pm
by Ann
rstevenson wrote:And what exactly was it your brother was smoking?
Rob
Certainly nothing back then. Possibly something now.
But I have the greatest respect for my brother's ability to remember all kinds of things from our childhood. So if he says it happened, I'll take his word for it.
That guide must have known a few tricks he could use to impress gullible tourists, though!
Ann
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Mon May 01, 2017 3:11 pm
by ildiora
if you go to Rifugio Sapienza, you can take the cableway and then from there the jeeps with guides up to the top!
ciao
Dario
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Mon May 01, 2017 5:28 pm
by neufer
ildiora wrote:
if you go to Rifugio Sapienza, you can take the cableway and then from there the jeeps with guides up to the top!
<<Eugene the Jeep is a character in the Popeye comic strip. A mysterious animal with magical abilities, the Jeep first appeared in the March 16, 1936, appearance of Thimble Theatre strip. He was also present in animated versions of Popeye's adventures, including three appearances in the Fleischer Studios shorts of the late 1930s/early 1940s, with more extensive appearances in later Popeye cartoons produced for TV.
In the August 9, 1936, strip, headlined "Wha's a Jeep?" [sic] Popeye asks Professor Brainstine what exactly a Jeep is. He gets the following response: “A Jeep is an animal living in a three dimensional world—in this case our world—but really belonging to a fourth dimensional world. Here's what happened. A number of Jeep life cells were somehow forced through the dimensional barrier into our world. They combined at a favorable time with free life cells of the African Hooey Hound. The electrical vibrations of the Hooey Hound cell and the foreign cell were the same. They were kindred cells. In fact, all things are, to some extent, relative, whether they be of this or some other world, now you see. The extremely favorable conditions of germination in Africa caused a fusion of these life cells. So the uniting of kindred cells caused a transmutation. The result, a mysterious strange animal.”
When asked if he had any further questions, Popeye, totally unenlightened by this explanation, repeated, "Wha's a Jeep?"
Many, including R. Lee Ermey, suggest that soldiers of World War II were so impressed with the then-new Willys MB that they informally named it after Eugene the Jeep as it was "small, able to move between dimensions and could solve seemingly impossible problems."
In Popeye Presents Eugene the Jeep (1940), Eugene was a gift to Popeye's girlfriend Olive Oyl from her Uncle Ben who found the Jeep in Africa. Eugene is a yellow creature about the size of a dog who walks on his hind legs. He has a bear-like head and ears but a large nose, long tail, and protruding belly. The Jeep's diet consists only of orchids. As his language is limited to the word "jeep," Eugene primarily communicates through body language. Eugene always tells the truth, even to crooks. He possesses high intelligence, so is able to help humans such as Popeye and Olive Oyl solve complex problems. He makes use of a limited form of teleportation: he can disappear from one place and reappear in another, and can walk through and on walls and ceilings. These teleportation powers are said to stem from the Jeep's ability to cross into the fourth dimension.>>
Re: APOD: Mt. Etna Lava Plume (2017 Apr 26)
Posted: Fri May 05, 2017 7:01 pm
by ildiora
This post reply is really funny!!!!..... but it does not discuss about this APOD as it should do. If you do not know what a jeep is, a quick search on google would be helpfull for you but not for topic of this tread.
Clear sky!
Dario