Mount
Etna, towering above Catania, Sicily's second largest city, has one of
the world's longest documented records of historical volcanism, dating
back to 1500 BC. Historical lava flows of basaltic composition cover
much of the surface of this massive volcano, whose edifice is the
highest and most voluminous in Italy. The Mongibello stratovolcano,
truncated by several small calderas, was constructed during the late
Pleistocene and Holocene over an older shield volcano. The most
prominent morphological feature of Etna is the Valle del Bove, a 5 x
10 km horseshoe-shaped caldera open to the east. Two styles of
eruptive activity typically occur at Etna. Persistent explosive
eruptions, sometimes with minor lava emissions, take place from one or
more of the three prominent summit craters, the Central Crater, NE
Crater, and SE Crater (the latter formed in 1978). Flank vents,
typically with higher effusion rates, are less frequently active and
originate from fissures that open progressively downward from near the
summit (usually accompanied by strombolian eruptions at the upper
end). Cinder cones are commonly constructed over the vents of
lower-flank lava flows. Lava flows extend to the foot of the volcano
on all sides and have reached the sea over a broad area on the SE
flank.
Sicily's
greatest natural attraction is also its highest mountain. To the ancient Greeks,
Mount Etna was the realm of Vulcan, god of fire, and the home of the one-eyed
monster known as the Cyclopses and where the giant Enceladus laid (eruptions
being his breath and earthquakes his motion).
Eruption
of Etna Volcano December 2006 video Thomas Reichart
At approximately 3350 meters, it is Europe's
highest active volcano. The size of the summit changes with each eruption, and
over the centuries a few lava flows have reached the coast. Over 1200 square
meters of Etna's surface is covered with solidified lava. Etna offers skiing in
the Winter months and breathtaking hikes in the woods during the Summer. There
are also a number of smaller peaks on the slopes of Etna, and some interesting
caverns. Since Etna is a strato volcano, with relatively cool lava temperatures
and numerous openings (vents), nobody ever knows precisely where on its vast
surface the next eruption will be.
There
was a series of eruptions on Etna in January and June which showered local
villages with ash but caused no damage or injuries. Some believe this may be a
prelude to the volcano's first significant eruption in six years.
Etna
- named after the ancient Greek word for "I burn"
Etna
is the highest active volcano in Europe at more than 10,000 ft (3,200 m).
Greeks
legends say Etna was the workshop of Hephaestus and the Cyclops. Underneath
the giant Typhon lay, making the Earth tremble when he turned.
Etna
covers an area of 600 square miles
Geologists
estimate it to have been active for more than 2,500,000 years.
NASA
Jacques Descloitres, MODIS Land Rapid Response Team Satellite: Terra Sensor:
MODIS
The
Eruption of Mt. Etna NASA TERRA
Located
near the east coast of Italy's province of Sicily, Mount Etna is Europe's most
active volcano and is one of the world's largest continental volcanoes, standing
about 3,350 m (10,991 feet) tall. Mount Etna has a broad base (or shield)
spanning roughly 60 by 40 km (36 by 24 miles) and reaching an altitude of about
2,900 m (9,500 feet). The remaining 400 m (1,200 feet) at its top is a
stratovolcano made from several vents that have coalesced.
Most of the surface of Mount Etna
is covered by historic lava flows dating back to eruptions as old as 300,000
years. Scientists believe Mount Etna started as a submarine volcano that
gradually grew to stand above sea level on layer upon layer of solidified lava.
Among all the world's volcanoes,
Mount Etna has the longest recorded history of eruptions, dating back to 1500
B.C. Since then, the volcano has erupted about 200 times and has been very
active in recent decades. In particular, 2001 has been a busy year for Mount
Etna, as there have been 16 eruptive episodes to date. The most recent began on
July 13, 2001, accompanied by earthquakes and the opening of at least five vents
on the volcano that released thick lava flows and vast columns of steam and
smoke. Officials have been watching closely as the lava flowed to within 5 km (3
miles) of the town of Nicolosi (as of July 21).
NASA/GSFC/MITI/ERSDAC/JAROS,
and U.S./Japan ASTER Science Team Satellite: Terra Sensor: ASTER
These perspective views of Mount
Etna were acquired by the Advanced Spaceborne Thermal Emission and Reflection
Radiometer (ASTER), flying aboard NASA's Terra
satellite. The top image is a false-color image, acquired July 5, 2001, and
produced using a combination of ASTER's visible and near-infrared channels. In
that image, the blue-white pixels on the volcano's north slope are snow. The
dark brown and black pixels radiating out away from Etna's caldera are exposed
rock surfaces from previous lava flows. The deep red hues around the edges of
the image indicate the presence of vegetation.The bottom pair of images were
acquired by ASTER on June 22 (left) and July 5, 2001 (right). They were produced
using ASTER's thermal infrared (heat) detector. The bright yellow-white pixels
show the lava dome at the top of Mount Etna, as well as the locations of several
vents, where heat is escaping.
These Multi-angle
Imaging SpectroRadiometer (MISR) images capture the July 22, 2001 explosion of
the Mt. Etna volcano.At the bottom of this image set are true-color views from
MISR's 70-degree forward-viewing camera, the vertical-viewing (nadir) camera,
and the 70-degree backward-viewing camera. Each covers an area of 143 kilometers
x 88 kilometers. The upper image is a stereo anaglyph created from the
instrument's 70-degree and 46-degree forward views, and covers an area of 438
kilometers x 300 kilometers. To facilitate stereo viewing, the images are
oriented with north at the left. Viewing the stereo image in 3-D requires
red/blue glasses with the red filter placed over your left eye. Two plumes of
differing compositions are seen to be emanating from Etna. The bright, brownish
plume drifting southeast over the Ionian Sea is composed primarily of tiny
frozen fragments of lava, known as ash. A fainter, bluish-white plume is also
visible, especially near the summit, and is most apparent in the 70-degree
forward view. It contains very fine droplets of dilute sulfuric acid. In
addition to the particulate plumes visible in these images, the volcano also
expels gases such as water vapor, sulfur dioxide, and carbon dioxide.
Activity on
Mount Etna
In late June 2008,
Sicily’s Mount Etna was releasing continuous plumes of ash and steam,
according to the U.S. Air Force Weather Agency. The Advanced Spaceborne Thermal
Emission and Reflection Radiometer (ASTER)
on NASA’s Terra satellite caught the
volcano’s activity in this picture taken on June 21, 2008. The volcano
continued releasing plumes in early July.
In this false-color image, made
with a combination of visible and infrared light, vegetation appears bright red,
bare ground appears charcoal, and the volcanic plume ranges in color from nearly
white to pale blue. Signs of past eruptions appear in the rivulets of rock left
over from old lava flows that spread out from the summit.
Mount Etna is a stratovolcano
composed of alternating layers of hardened lava, solidified ash, and rocks
ejected by past eruptions. The plume shown in this image is mild compared to
some of Etna’s past activity. Records of the volcano’s activity data back to
1500 BC. At 3,330 meters (10,925 feet) high, Etna towers over Catania,
Sicily’s second-largest city.
NASA image created by Jesse
Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and
U.S./Japan ASTER Science Team.
Caption by Michon Scott.
credit: NASA, The Discovery
Channel, The Smithsonian Institute, USGS, Volcano World
Data
compiled from The British Antarctic Study, NASA, Environment Canada,
UNEP, EPA and
other sources as stated and credited Researched by Charles
Welch-Updated dailyThis
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