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
  b# Y- k4 d( Q$ r6 p. S& l8 E' eeruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are
% j+ m/ H7 t. w- Y5 ?active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.
: c7 |! c9 F9 y3 u# ]公仔箱論壇Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens,
' l: ]; u6 s" M, h* q$ r4 U公仔箱論壇erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous 公仔箱論壇3 ^4 z1 S0 ~3 K  b' m: z7 T! E
and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions.
) W, ^/ c- _! F1 @/ [. Qtvb now,tvbnow,bttvbThey tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.
: ]7 o, e& w( c9 U
2 L& F, {7 O$ P! _) M/ m' U$ R( {5.39.217.76
1 i# b- R2 H( N% ~, a2 w! v  rTVBNOW 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。公仔箱論壇/ V/ R$ [) @' D+ K5 R6 C2 u9 n3 n8 T7 D
Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above
2 V  y2 ]; P9 j; k/ lof Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas
- ^8 x. ]' J7 O2 V5 b' WTVBNOW 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。taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash tvb now,tvbnow,bttvb; w. v, R3 h+ `  I- n2 Q$ Q
plume reached as high as 50,000 feet.3 @3 M5 v8 L4 l
公仔箱論壇5 t+ v  a3 O+ u0 w# x* a
公仔箱論壇8 b& m1 t7 O# |$ e$ Q) I4 c
公仔箱論壇& z5 K, z9 |- o  I" g
Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra 公仔箱論壇: U% v9 E: O, m1 h) Z$ Y
satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
0 S+ c9 g# s, V& S( `5 H0 n( k公仔箱論壇years. The island’s jagged edges were created by massive avalanches.5.39.217.76. F7 ~, l9 F4 U4 w3 `, p; 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。8 I6 C& R( w# L
Augustine lies in the Cook Inlet at the eastern end of the Aleutian trench which marks the northernmost portion of the Pacific Ring 1 E. N" f# T+ [
of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
+ @; @3 N  s6 I  u+ htvb now,tvbnow,bttvbocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of
4 g4 M) O" o5 R公仔箱論壇the continental crust, creating magma that drives the volcanic eruptions
. i% g2 E+ X6 |7 k, \! 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。5.39.217.76# D, f0 m  k9 K2 v/ N! K

) v$ b+ W# p0 B% [" o公仔箱論壇
; v3 z( g( M* r8 Mtvb now,tvbnow,bttvbAstronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev Volcano ( R, H) V& {4 m# a4 _1 s
in the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.5.39.217.76* e5 Q- A2 [& N7 k2 K/ B! B
tvb now,tvbnow,bttvb8 X. Z/ Z" W4 x! O
The smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising 5 h# v. x' @' E" R2 \2 B, L) g
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 tvb now,tvbnow,bttvb0 M# y3 z8 J) Q
as a pyroclastic flow.
4 W; `7 N# \/ y% i/ @0 }公仔箱論壇5 I: p0 d( B# v/ i! R5 D3 L
This photo sparked a debate among scientists about what caused the hole in the clouds above the eruption. Three possible options came up:
+ X  h( K: R8 U# v9 ~" K5.39.217.765.39.217.766 E6 I8 g8 H! B0 [- _1 V* f
    * It could have nothing to do with the eruption and simply be caused by the contrast in temperatures between the ocean and the island.
: ^# @5 S) Z7 K1 p& @5.39.217.76    * A shockwave from the eruption could have blown a hole in the cloud deck.5.39.217.763 m; d$ j: a* x$ y
    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.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 p* T6 h1 v+ P- H$ U7 j1 J9 Q3 m0 |

& v8 U% V7 X# g& V. [9 w5.39.217.76# z& [7 \. j* Z$ B, f  C
5.39.217.762 g$ G! k( z2 S% d5 b# s) ?
Alaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
, j; t) H- c, d: K8 P4 _It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when
" v4 N; e! @, C8 r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.
) M- ~( E; h' M" z5 b. {1 F0 \8 b5.39.217.76
8 a: Q4 H3 g- N7 G  T( S  t' \8 {# e5.39.217.76Redoubt 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。% o5 E5 j6 T! s/ \8 i; u: F
2 `  `8 W- s) O

  L) T6 z% t( ?# J! F2 D, L9 A# rTVBNOW 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。
$ l6 S! s/ s% |tvb now,tvbnow,bttvbMount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in公仔箱論壇+ f! y3 H5 U/ x' R6 `
the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one
) J7 L+ ~# A2 V公仔箱論壇captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in 1 e. E, ~" ^) D5 c
this picture are from forest fires ignited by lava.5.39.217.760 b9 `' T! o/ k8 D8 |1 C

3 }2 D  g( G* |( v  [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。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 may
" S  V6 @& A/ |" X1 `/ C, F: [公仔箱論壇also be the oldest-known active volcano.
4 d8 [3 K& d5 t. y公仔箱論壇
& p! }: ]) i6 ^  o4 \  P5.39.217.76
5 F% _! P/ U8 w% [6 j
% }. D- D. K2 q/ j; OA NASA astronaut spotted this eruption of Cleveland Volcano from the International Space Station in 2006. The volcano is 5,700 feet high / m( K' f0 j6 d8 ^
and claimed the only known eruption-related death in Alaska’s Aleutian Islands in 1944. Its symmetrical, cone shape is typical of stratovolcanoes.tvb now,tvbnow,bttvb  b* L* [1 B% b2 H. u* k
1 [6 I4 r5 O+ ?- N& f0 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。) Y5 n$ G& O( b/ j7 Q. [( n+ W) K* k9 o
+ ~2 ~/ J4 s  ~3 O* z
Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City. 5.39.217.76. T! G, C0 j/ v3 B+ f% E
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 5.39.217.763 B, b7 v# H/ E+ T' q' D& G. x
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
. g2 D* E5 Z$ ~1 W' X# 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。of frequent activity. The plume reached heights of around 30,000 feet.公仔箱論壇; h) J  n7 t% d8 h) r% N, A5 A

3 p5 {" b6 p" Y0 u8 x; H5.39.217.76
+ v$ E9 p) V/ U& u6 |+ ~( A* O公仔箱論壇公仔箱論壇( r5 t. w- r% V  C+ `* N% q9 f

- B' ^2 U. u, B5.39.217.76
5 O# [& K- H8 p( I; j. w7 \9 F公仔箱論壇This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the 0 {& M4 {2 I$ j: I  X, J& V/ ]4 L
west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.tvb now,tvbnow,bttvb8 N& f/ q" f9 ^& b
' Z1 f- U' B7 X, O; ?
Chaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic
6 I9 a% f! Y$ s1 Q7 }- z3 O% e公仔箱論壇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.5.39.217.762 k9 I4 \$ s4 x/ |: M# G
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。( l* Y5 J" m1 v' ^! |1 n" i* L
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 d, M8 J* y, }7 k' Q

' ]; }$ O6 p8 r. PThis image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra 3 \/ K! a  R4 w+ A% `) L
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 $ ^8 V# a% G" k. ]" P/ S
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
! x/ W' S- Q/ X- W! L$ f2 d公仔箱論壇stationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.tvb now,tvbnow,bttvb  ]$ z& I% h/ p: J1 X! Q8 O& M
5.39.217.764 ?6 M5 I9 R+ ~/ `% f

" E( ~( M4 t; U; r' QTVBNOW 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。
- k. F3 m* O9 V7 I7 v- r% [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。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.
! u: B1 ~. z2 C" d1 C& G5 {( m, }( A& ntvb now,tvbnow,bttvbA 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 tvb now,tvbnow,bttvb) v* ]. v4 u( k" \1 U; i' S
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,
* o# C9 Y% z8 G( @. Qcausing 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