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Erupting Volcanoes on Earth as Seen From Space

One of the most violent but beautiful reminders that we live on ageologically restless planet are volcanic
: P; j$ ^' A9 F2 k1 O" N2 J! S公仔箱論壇eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are # k! ^5 ~, w5 T: }% \0 q
active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.
4 b5 ]3 V4 ?: b; S# K% C2 M6 ySome volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens, & F# L6 |6 A; M/ v& f; o. Y2 D
erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous tvb now,tvbnow,bttvb5 F' E8 @# E3 ]+ S' o( v& X# `
and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions. tvb now,tvbnow,bttvb) V$ @" R6 B' u4 O
They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.
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Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above   `7 x& W& f  S; u2 r
of Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas8 }0 Q  v- }* N# d3 @
taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
3 e! x* L8 @6 n* f0 g' `% f公仔箱論壇plume reached as high as 50,000 feet.
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TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。$ o6 ?5 E3 }6 G5 p  ~

) v. d% O# ^- p2 F. pTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
) N# r* b- e7 j公仔箱論壇satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000 TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。. t! l1 B% G9 H! g) U
years. The island’s jagged edges were created by massive avalanches.
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Augustine lies in the Cook Inlet at the eastern end of the Aleutian trench which marks the northernmost portion of the Pacific Ring
7 W$ S" q7 L' G公仔箱論壇of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet tvb now,tvbnow,bttvb* r4 b1 o+ q% s
ocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。4 _; u7 A! W& v$ {- }5 k2 Z
the continental crust, creating magma that drives the volcanic eruptions5.39.217.77:8898* n' p+ P5 E; N) E/ |: t
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. Y  W; _- z( U' ~1 o5.39.217.77:8898Astronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev Volcano
( ?! Q1 s6 G" X+ i; H- Etvb now,tvbnow,bttvbin the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.5.39.217.77:8898: o" j  j% L. z+ R6 |7 M; U
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The smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising ) c4 |& Z# L: L: q" L
and cooling of the air above. In contrast, a dark gray cloud of ash near the ground is probably an avalanche of hot ash and rock known 公仔箱論壇4 s9 r6 j# C4 Q, d  L2 U* _
as a pyroclastic flow.tvb now,tvbnow,bttvb2 q% c/ G1 }/ V) C% k7 I
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This photo sparked a debate among scientists about what caused the hole in the clouds above the eruption. Three possible options came up:
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    * It could have nothing to do with the eruption and simply be caused by the contrast in temperatures between the ocean and the island.
7 j) @8 l! R+ z$ o5 v2 g3 P0 n3 c+ tTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。    * A shockwave from the eruption could have blown a hole in the cloud deck.5.39.217.77:8898( I- s, _+ j- {; w/ I, b2 r8 ^1 j
    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.
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" L# q" O- b9 K+ z9 fAlaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
0 M$ k0 ^2 `- yTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when
  Z0 B. M6 B$ s7 m$ C: r* s公仔箱論壇 the ash reached heights of 27,000 feet. The volcano’s alert level is still “advisory,” and the aviation color code is yellow.
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Redoubt is a 10,200-foot tall stratovolcano 100 miles southwest of Anchorage in the Aleutian Range, west of the Cook Inlet.
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Mount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in
- X) O2 w2 B4 B: z: m! U- ~' H5.39.217.77:8898 the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one
, h* j& ^# T9 s: scaptured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in
/ N& M" [& d6 X7 ^. I1 g2 jthis picture are from forest fires ignited by lava.5.39.217.77:8898$ b- o( B' B1 a* e& P

1 ]0 `7 d# Y7 u# g( S5.39.217.77:8898Etna is a stratovolcano located on the island of Sicily. It is one of the most studied volcanoes in the world and. at 500,000 years old, it maytvb now,tvbnow,bttvb$ F( D% @& }/ n: S% ~+ r  y) ~7 V9 `
also be the oldest-known active volcano.9 |! i' N  i- K8 H% g/ ?; l  ]5 w
TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。! f7 v% @# h6 b- T+ g

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! R7 g7 U2 p, l4 s3 C- y; ~TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。A NASA astronaut spotted this eruption of Cleveland Volcano from the International Space Station in 2006. The volcano is 5,700 feet high tvb now,tvbnow,bttvb, N; u% V1 }8 I# X# B7 v
and claimed the only known eruption-related death in Alaska’s Aleutian Islands in 1944. Its symmetrical, cone shape is typical of stratovolcanoes.
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2 \0 [6 Q2 c+ A2 U* yPopoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City. TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。! s1 q* Q4 {  \# F) I: i- G
The second highest peak in Mexico at 17,800 feet, this glacier-covered stratovolcano has erupted at least 20 times in the last 500 years and has caused TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。) f. o% B8 y6 a, R/ ~7 l7 ~
multiple evacuations of the city. This eruption in 2001 was caught by astronauts on the International Space Station, near the end of a seven-year period 公仔箱論壇4 c( o& T0 Y/ q+ }
of frequent activity. The plume reached heights of around 30,000 feet.
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This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the
' ?* H4 I  x! Xwest coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.
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2 V1 |7 K6 M( S' I3 ?Chaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic
, U- c! W- Y4 i! c1 y+ kflows and volcanic mudflows called lahars. The caldera is relatively small at less than two miles wide, and sits on the flank of the larger Michinmahuida volcano.
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This image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra ( v7 T7 K) @1 t0 V$ s
is a shield volcano, which are made mostly of previous lava flows and tend to be broad and gently sloping. The Galapagos are part of an island chain
& M  r2 ~  j5 _. Ptvb now,tvbnow,bttvbformed by a hot spot where a plume of hot mantle rises up and melts the base of the ocean crust. As the Pacific plate moves over the relatively
0 W/ u7 h0 u) Y, a/ |" j, Lstationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.: f* s! @4 n6 i) S
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  M  s$ P: @3 Etvb now,tvbnow,bttvbNASA’s Terra satellite snapped this image of Shiveluch volcano erupting on Russia’s Kamchatka peninsula at the edge of the Pacific Ring of Fire in 2004.
+ ~$ G1 q: E. [" U% N; kA lava dome had been growing in the volcano’s crater, followed by intermittent eruptions that lasted weeks. Shiveluch is a 10,400-foot-high stratovolcano
/ l+ b( V  A& H4 c0 rthat is at least 60,000 years old and has been erupting fairly often for the past 10 years. Its dome has collapsed multiple times, most recently in 1964, 5.39.217.77:88980 T$ F' g7 }4 [% j* ]6 Q1 w) `- ~
causing avalanches of debris into the crater.

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唔知自已寫乜好唔識形容
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