返回列表 回復 發帖

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 tvb now,tvbnow,bttvb" f+ ^, e( u3 K, G6 m0 c
eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are 公仔箱論壇3 v1 q5 Q: M# |, w' x  _
active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.公仔箱論壇" C* t! J3 i, t
Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens, 公仔箱論壇  e& \3 B% p" o* V. k) I
erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous
/ C! R5 _! O- e4 }* x0 r- cand explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions. 公仔箱論壇/ e# _* B  c6 S4 a5 k5 b, a9 Q
They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.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。# n4 K, W0 X; V+ M) o( R

& K( z$ T0 K$ r% J0 ?* M+ V8 A2 H4 t: Y7 t9 K! M& j& P. S

. y* u1 i& L( h* U. n# Z( wtvb now,tvbnow,bttvbMany of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above
4 L4 B- o' [! U$ J: Xof Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas公仔箱論壇8 X% R9 x4 L" |3 b
taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash 公仔箱論壇9 f% X0 N# h' ]+ j; U- V
plume reached as high as 50,000 feet.8 m9 C: J% E; E& J0 [: T
! q* d# E: \; W8 @  M" M  N
+ S/ A' O6 }7 _2 k* w! M
5.39.217.767 H7 ^2 J  C9 S: }& o( z8 T
Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
2 d( R- E& Q. i% f4 A- ntvb now,tvbnow,bttvbsatellite 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。& N+ [  c6 w5 o  i- ~
years. The island’s jagged edges were created by massive avalanches.- F6 u& p" }% Z$ t* O" }
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。% S* e% e' G1 J
Augustine lies in the Cook Inlet at the eastern end of the Aleutian trench which marks the northernmost portion of the Pacific Ring
; T1 a2 T, w4 ?) \  e3 wof Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet 5.39.217.769 f% G5 e6 Z! \
ocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of tvb now,tvbnow,bttvb# W/ r; {4 E3 k5 h- S
the continental crust, creating magma that drives the volcanic eruptions公仔箱論壇$ @6 C6 k# D2 k' }% }9 ], T% O( H
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。+ h$ Y6 E3 N8 c" i% T* R  G% i5 e
tvb now,tvbnow,bttvb& v" P1 t- E7 O" ?% S' d  f
tvb now,tvbnow,bttvb7 J- b  ?( O8 Q0 ~
Astronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev Volcano tvb now,tvbnow,bttvb; ?) M% g) Z' T. C0 C( [
in the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.
# K$ W- a- R+ K# d3 f- ]9 S) @4 g- 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。1 [- [# x; j7 |: q
The smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising
  n4 U$ e2 I" l$ M, J# Y: h5.39.217.76and 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
9 \+ D; a8 R9 O) [as a pyroclastic flow.tvb now,tvbnow,bttvb% g$ a% Q# T4 P( {0 g

  B, H% t' Y2 A' f5.39.217.76This photo sparked a debate among scientists about what caused the hole in the clouds above the eruption. Three possible options came up:
9 Q8 z% }/ n- KTVBNOW 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。! v/ e. \( t. e- X
    * It could have nothing to do with the eruption and simply be caused by the contrast in temperatures between the ocean and the island.
1 q2 Y; d! P8 H" g# i2 E. C  D( ^    * A shockwave from the eruption could have blown a hole in the cloud deck.
* w2 E; R+ l% k2 t* ?3 a; F公仔箱論壇    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.2 z% w3 J3 G6 P3 n$ I# o1 O2 S( S* T: q
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。0 l) h# T. ^7 i/ s& o
. E4 i/ o  }9 V- ^( M9 w# ?' R  I3 D

% ?+ Z' J  U3 p' A  g" aAlaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet. tvb now,tvbnow,bttvb0 s3 n& b4 ]  W: a! p7 o
It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when公仔箱論壇% X4 n. s2 k0 ?5 p) v' K
the ash reached heights of 27,000 feet. The volcano’s alert level is still “advisory,” and the aviation color code is yellow.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。! v! D. O4 W0 b# V" k# V

; D$ \) N! {4 O6 X5 A9 e4 {公仔箱論壇Redoubt is a 10,200-foot tall stratovolcano 100 miles southwest of Anchorage in the Aleutian Range, west of the Cook Inlet.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。+ i! m) G- n  ~6 O4 ^5 R
tvb now,tvbnow,bttvb/ |. p% r* V) W9 C" t
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。9 g7 t/ w2 R( ?& T3 e% C1 A# e, v7 ]
tvb now,tvbnow,bttvb2 Q) I+ h' \* X  b: K. O! o  q# W  B
Mount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in
, u( l6 d( \! [* Q" I4 x7 P5 utvb now,tvbnow,bttvb the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one
4 w& `& P0 {' }0 b0 v% r" F$ W5.39.217.76captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in
& h9 g3 n  g" h1 }' m5.39.217.76this picture are from forest fires ignited by lava.
; T. {5 s9 V( Z, wtvb now,tvbnow,bttvb5 V* L  d& ~/ l% P: j, }/ j
Etna 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 may5.39.217.76/ V' Y" E# D, L9 ]; l, b+ q
also be the oldest-known active volcano.tvb now,tvbnow,bttvb0 n$ [8 S! J3 [) E2 f' m: _
& i% i5 k2 R3 [% `
公仔箱論壇) e- a+ G7 C# P$ y% Y0 G
tvb now,tvbnow,bttvb" w6 U$ r5 f: |: }
A NASA astronaut spotted this eruption of Cleveland Volcano from the International Space Station in 2006. The volcano is 5,700 feet high 5.39.217.765 w0 k# N4 G* B, e0 W. S% Q' t, ^
and claimed the only known eruption-related death in Alaska’s Aleutian Islands in 1944. Its symmetrical, cone shape is typical of stratovolcanoes.
- p% S: @8 N8 \6 m5.39.217.76TVBNOW 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。# b/ S, W& m* P2 U9 N# a, N
( ]' U0 w1 z8 W' Z# M8 Z$ {
: |! w* n4 g) K, Y3 G
Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City. 4 D, n( `9 F. m8 M6 o' q, Q$ ~8 R/ f
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
) H) v5 n, p) m$ y8 u5 N. f  `& K5.39.217.76multiple 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
  a' j3 t* g) z3 S公仔箱論壇of frequent activity. The plume reached heights of around 30,000 feet.
# l$ e3 b: r1 s  K$ M/ ?tvb now,tvbnow,bttvb6 X% |) n# ^8 N; w+ n" c

# x' G6 R/ Q/ A0 L1 I% \5.39.217.76& Y1 R; r4 w+ R9 V

9 F! i8 q1 p& i( \3 m5.39.217.76  w& E3 h4 ?' l3 N& n- r* \
This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the 5.39.217.76; j& K& e! E$ k' o4 _# k0 @
west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.) Z5 {, W  f; M8 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。6 p3 P& A7 [5 a) L
Chaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic
: ^0 ^% V3 x' v* XTVBNOW 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。flows 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.
' s9 n3 V( M! _8 X: @公仔箱論壇
! J1 ?* O7 Y& @: J2 ^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。tvb now,tvbnow,bttvb3 |! U3 y9 H7 W4 s

4 E3 ], x% u3 w' GThis image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra 公仔箱論壇5 B' U/ ~2 D' w! B
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 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。( q% ]+ U* x, @7 h& T' q* X
formed 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
' v$ n( T6 C: ^: q" ]0 N  ustationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.
8 c8 r: [. Q" ~- N8 C6 }tvb now,tvbnow,bttvb
% \+ t/ E% h+ [
  K6 t8 z8 E+ r( X$ S! ~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。9 H, H4 B% }2 v
NASA’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. . A2 h1 Y/ i1 f- d
A 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 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。2 i6 Y5 S$ Q& q  [0 o0 Q
that 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, tvb now,tvbnow,bttvb) `: m+ W/ t! h
causing avalanches of debris into the crater.

1

評分次數

  • k23bb

唔知自已寫乜好唔識形容
返回列表