In the olden days, people thought of them as punishments from the
god, but these days, we know it’s actually tectonic plates shuffling
and releasing the red-hot magma from the earth’s core. Volcanoes go
about their work silently, showing their presence in full might when
they are totally prepared catching the people around unawares. The
recent eruption of Eyjafjallajokull in April 2010 has made the list more
interesting than ever, an Icelandic volcano whose name only a few dare
to pronounce ,
made people realize once again how powerful the nature can be and how
destructive it might be. Still, it’s nothing compared to the calamities
eruptions may cause, wiping out cities and claiming thousands of
lives. Classification of the world’s most dangerous volcanoes is subject
to debate. Nothing ensures a date in history like a volcano
eruption, it happens just when the mother nature flexes her biceps
spewing ash and steam miles into the sky. Below are listed some of the
most dangerous and vigorous volcanoes due to their explosive history
and proximity to large populations.
10. Mauna Loa – Hawaii
Mauna Loa is the largest volcano on Earth in terms of volume and area
covered and one of five volcanoes that form the Island of Hawaii in
the U.S. state of Hawaiʻi in the Pacific Ocean. It is an active shield
volcano, with a volume estimated at approximately 18,000 cubic miles,
although its peak is about 120 feet (37 m) lower than that of its
neighbors.
The volcano has probably been erupting for at least 700,000 years.
Mauna Loa’s most recent eruption occurred from March 24, 1984, to April
15, 1984. In view of the hazards it poses to population centers, Mauna
Loa is part of the Decade Volcanoes program, which encourages studies
of the most dangerous volcanoes.
Mauna Loa is the world’s largest shield volcano in terms of area
covered. Mauna Loa is shaped like a shield, because its lava is
extremely fluid (it has low viscosity), and therefore although the
eruptions are not so explosive, the fluidity speeds up the lava causing
more fires and threat to the population.
9. Taal Volcano – Phillipines
Taal Volcano is a complex volcano on the island of Luzon in the
Philippines. It consists of an island in Lake Taal, which is situated
within a caldera formed by an earlier, very powerful eruption. It is
located about 50 km (31 Miles) from the capital, Manila. It is one of
the active volcanoes in the Philippines, all part of the Pacific ring
of fire.
The volcano has erupted violently several times, causing loss of life
in the populated areas surrounding the lake, the current death toll
standing at around 5,000 to 6,000. It was thought to be named as “a
volcano inside a volcano” because many believed that the lake that
circles the volcano was once a crater or mouth of a volcano.
One of the more devastating eruptions occurred in 1911, which claimed
more than a thousand lives. The deposits of that eruption consisted of
a yellowish, fairly decomposed tephra with a high sulfur content. The
last eruption was in 1977 but it has shown signs of unrest since 1991,
with strong seismic activity and ground fracturing events, as well as
the formation of small mud pots and mud geysers on parts of the island.
Recently, on 8th June’ 2010, the Philippine Institute of Volcanology
and Seismology rose its alert level, which indicates the volcano is
undergoing magmatic intrusion which could eventually lead to an
eruption.
8. Ulawun, Papua New Guinea
A steam plume over the sea from the Ulawun is clearly visible on a
satellite image. Ulawun is one of the most active volcanoes in Papua New
Guinea and one of its most dangerous. It is the highest volcano in the
1000 km long Bismarck volcanic arc. Ulawun volcano is composed of lava
flows interbedded with tephra.
The first recorded eruption of Ulawun was in 1700. Several thousand
people live near the volcano.There have been 22 recorded eruptions
since the 1700s. The last few years have seen almost constant activity
at Ulawun, with frequent small explosions. Eruptions originate from a
central crater. Its eruptions devastated the NW flank of Ulawun and
modified the summit crater. An eruption in 1980 ejected ash to 60,000
ft and produced pyroclastic flows which swept all flanks of the volcano
and devastated an area of 20 sq km. The most serious volcanic
hazard at Ulawun volcano is catastrophic structural collapse, producing
an eruption which could devastate hundreds of sq km in area.
Ulawun volcano is 400 m higher than most of the volcanoes in the
Bismarck which indicates it may be at the limit of structural
stability. Seismic activity remained high at Ulawun Volcano in 2008. A
magnitude 5.1 earthquake hit 10 km west of Ulawun volcano on 28th May
2009. On 14-15 February 2010 ash emissions from Ulawun volcano reached a
height of 3.7 km and drifted 95 km.
7. Mount Nyiragongo – DR Congo
Nyiragongo volcano is one of the most active volcanoes in Africa. It
is noted for long active lava lakes which appear in the summit crater.
Nyiragongo is one of eight volcanoes in the Virunga Mountains. The
volcano is located near the town of Goma in the eastern Democratic
Republic of Congo. It is a stratovolcano located inside Virunga National
Park. Apparently, nowhere else on the globe does such a steep-sided
stratovolcano contain a lake of such fluid lava like Nyiragongo.
Nyiragongo’s lava lake has at times been the most voluminous known lava
lake in recent history.
Since 1882, it has erupted at least 34 times, including many periods
where activity was continuous for years at a time. The last
devastating eruption of Nyiragongo occurred on 17th January 17,
2002, when lava flows down the flank of Nyiragongo covered
approximately 40% of the town of Goma, rendering at least 120,000
people homeless, displacing most of Goma’s population of 500,000. This
volcano is currently active, with Nyiragongo in an eruption that has
been ongoing since May 2002. Nyiragongo’s lava lake remains
active to this day.
Since January 2009, recurrent seismic swarms have been detected at
Rusayo seismic station. The volcanic earthquakes have come mainly from
Nyiragongo volcano, which contains an active lava lake. According to a
report by scientists from the volcano observatory in Goma the same
signs that preceded the 1977 and 2002 eruptions have been identified.
Possibly this means another eruption in near future.
6. Mount Merapi – Indonesia
Mount Merapi (literally Mountain of Fire) is a conical volcano
located on the border between Central Java and Yogyakarta, Indonesia.
It is the most active volcano in Indonesia and has erupted regularly
since 1548. It is very close to the city of Yogyakarta, and thousands of
people live on the flanks of the volcano.
Merapi is one of the most active volcanoes in Indonesia and has
produced more pyroclastic flows than any other volcano in the world. It
has been active for 10,000 years. Most eruptions of Merapi involve a
collapse of the lava dome creating pyroclastic flows which travel 6 to
7 km from the summit. Some flows have traveled as far as 13 km from the
summit, such as the deposit generated during the 1969 eruption.
Velocity of these flows can reach up to 110 km/hour. A slow up flow of
magma leads to an extrusion of viscous magma, which accumulate and
construct a dome in the crater.
There has been no late eruption. Typically, small eruptions occur
every two to three years, and larger ones every 10–15 years or so. Its
volcanic devastation is claimed to have led to the collapse of the Hindu
Kingdom of Mataram. Since 2006, there is increased seismicity at more
regular intervals and a detected bulge in the volcano’s cone indicating
that fresh eruptions were imminent. Authorities put the volcano’s
neighboring villages on high alert and local residents prepared for a
likely evacuation. The eruption in 2006 was followed with quakes of
long-period oscillation rendering over 3,00,000 people homeless.
5. Galeras – Colombia
Galeras has been an active volcano for at least a million years. It
is located in southern Colombia close to the border with Ecuador. Its
summit rises 4,276 metres above sea level. It has erupted frequently
since the Spanish conquest, with its first historical eruption being
recorded on December 7, 1580. It is currently the most active volcano in
Colombia. The city of Pasto with 450,000 inhabitants is located on the
eastern slope of Galeras.
Galeras became active again in 1988 after only a 10 years of
dormancy. A Decade Volcano conference in the city of Pasto, in 1993,
ended in disaster when several of the scientists present mounted an
impromptu expedition on 14 January to the crater of Galeras. An
eruption occurred unexpectedly while they were at the summit, which
resulted in the deaths of six scientists and three tourists.
The volcano has been erupting almost every year since 2000. It is
dangerous because of the frequency of unexpected eruptions and the
number of lives it has claimed. Two small eruption occurred in 2000
after seven years of quiet at Galeras volcano. The eruptions were
preceded by tornillo earthquakes. A hydrothermal eruption occurred in
2002 which ejected lapilli, ash, and clay. Elevated levels of gas
emission were recorded and in November 2004 there was an explosive
eruption at Galeras. An eruption with shock waves felt as far away as
miles was seen in 2005. Between January and June 2006 a lava dome
continued to grow in the crater at Galeras volcano. In following
years, there was a four-fold increase in daily long-period earthquakes
and many eruptive explosions were seen. Ash plumes were visible at
Galeras volcano that reached a maximum height of 6 km above sea level.
Thousands of people were evacuated from the area. And most recently, the
volcano erupted on January 3, 2010, forcing the evacuation of 8,000
people. This is the 10th such eruption of the volcano in the past year,
and the first of 2010. Ash was ejected to a height of 12 km. Hot lava
fell 3.5 km from the volcano and started fires. Colombian authorities
also stated that it could remain volatile in the weeks to come.
4. Sakurajima – Japan
Sakurajima is an active composite volcano and a
former island (now connected to the mainland) of the same name in
Kyūshū, Japan due to the lava flows of the 1914 eruption which caused
the former island to be connected with the Osumi Peninsula in Japan. It
is often called the Vesuvius of the east, and has been erupting almost
constantly.
The volcanic activity still continues, dropping large amounts of
volcanic ash on the surroundings. Earlier eruptions built the white
sands highlands in the region. Thousands of small explosions occur each
year, throwing ash to heights of up to a few kilometers above the
mountain. It is dangerous because of its location in a densely populated
area, with the city of Kagoshima’s 700,000 residents just a few
kilometers from the volcano.
Sakurajima’s activity became more prominent again in 1955, and the
volcano has been erupting almost constantly ever since, with 7,300
eruptions recorded in the last 45 years. In light of the dangers it
presents to nearby populations, Sakurajima was designated a Decade
Volcano in 1991, identifying it as worthy of particular study as part
of the United Nations’ International Decade for Natural Disaster
Reduction. The city has even built special shelters where people can
take refuge from falling debris. On March 10, 2009, Sakurajima erupted,
sending debris up to 2 km away. An eruption had been expected
following a series of smaller explosions over the weekend.
3. Popocatépetl – Mexico
Popocatépetl is an active volcano and, at 5,426 m
(17,802 ft), the second highest peak in Mexico and lies in the eastern
half of the Trans-Mexican volcanic belt, is a natural born killer which
could be a serious threat to the capital city (inhabited by fairly 9
million people). The residents of Puebla, a mere 40 km east of the
volcano, enjoy the views of the snowy and glacier-clad mountain almost
all year long. The name loosely translates to “smoking mountain” and the
volcano has had more than 20 known eruptions since 1519.
The latest episode began in December 1994 and there’s been almost
continuous volcanic activity ever since. The last major eruption was in
the year 2000. Thankfully, scientists were able to warn the Mexican
government and had thousands of people evacuated from the area. The
eruption in December of that year was the largest documented, most
likely in thousands of years.
Mexican culture has accounts of this mountain. They say Iztaccíhuatl
was a princess in an Aztec tribe. When she came of age, her father
wanted her to marry an Aztec prince; but she wanted to marry
Popocatépetl. This made emperor furious but agreed to it on one
condition: Popo’s tribe must help the his troops in a war. He intended
on Popo dying in the war. Popo and his tribe joined the Aztecs in war,
but they abandoned them at the height of battle. Miraculously, they
were still triumphant. Even so, the emperor told Iztaccíhuatl that Popo
had died, and wrote a letter to Popo saying Iztac died of sadness.
Popo did not believe, sneaked into the palace to and ran away with her
to get married, they lived happily for a few years. Suddenly, Iztac got
sick and died. An earthquake occurred. A voice from heavens ordered
Popo to bring her body to the peak. He obeyed and then laid down next to
her and waited to die. Years later, snow covered them and they became
two mountains. The two mountains are named after the lovers to this
day.
2. Mount Vesuvius – Italy
Mount Vesuvius is a stratovolcano on the Bay of
Naples, Italy, about 9 kilometres east of Naples and a short distance
from the shore. It is the only volcano on the European mainland to have
erupted within the last hundred years. Mount Vesuvius is best known for
its eruption in AD 79 that led to the destruction of the Roman cities
of Pompeii and Herculaneum, the ruins of this volcano stand to tell the
story.
Vesuvius has erupted many times since, most recently in 1944 and is
today regarded as one of the most devastating volcanoes in the world
because of the population of 3,000,000 people living nearby and its
tendency towards explosive eruptions. It is the most densely populated
volcanic region in the world. A two week long eruption of Mt Vesuvius
volcano began on 18th March 1944 with a lava flow from the summit
crater. Eruptions changed to explosive activity on 21st March with
eight lava fountains. The lava fountains increased with time, and the
last one on 22nd March was the most intense, reaching heights of 1000
m.
The volcano has an eruption cycle of about 20 years, so we are lucky
that it didn’t explode for many years over. Since 1944, seismicity at Mt
Vesuvius has been marked by moderate-energy events with a frequency of
a few hundred per year.
1. Yellowstone Caldera, United States
It is most dangerous because it is an active super-volcano which
means a volcano capable of producing a volcanic eruption with ejecta
greater than 1,000 cubic kilometers which is nearly a thousands of
times larger than most historic volcanic eruptions. Super volcanic
eruptions typically cover huge areas with lava and volcanic ash
sufficient to threaten the extinction of species and can even be one of
the causes to bring end to the world because once this volcano erupts, it causes all other volcanoes to erupt causing massive tectonic activity.
One of the largest supervolcanoes in the world lying beneath
Yellowstone National Park and scientists say it is still active and even
the activity is increasing! Though the Yellowstone system, which spans
parts of Wyoming, Montana and Idaho, is active and expected to
eventually blow its top, scientists think it will erupt any time soon.
Supervolcanoes can sleep for centuries or millenniams before producing
incredibly massive eruptions that can drop ash across an entire
continent.
Erupting every 6 lac years and it’s already 40 thousand years over,
significant activity is mounting beneath the surface, scientists say it
can erupt anytime. Back to 640,000 years ago, the area that we know as
Yellowstone National Park was the epicenter of a cataclysmic volcanic
eruption—an eruption one thousand times larger than Mt. St. Helens. The
eruption blasted away mountains, unearthed a vast ocean of lava and
spewed hundreds of miles of debris into the atmosphere, burying half of
the United States with deadly ash. Largely unknown today, this
destructive super volcano is still active, turning the picturesque
landscape of Yellowstone into one of the harshest environments on the
planet. Due to the volcanic and tectonic nature of the region, the
Yellowstone Caldera experiences between 1000 and 2000 measurable
earthquakes a year, though most are relatively minor. Brutally cold
winters fade into majestic summers, but for the animals that call the
park home—including Yellowstone’s great icons: the grey wolf, grizzly
bear, buffalo and antelope—this unique and hostile land creates a
daily, dramatic battle for survival. Yellowstone captures the essence
of this bitter and mercurial environment as it follows the animals that
live in the midst of this treasured wilderness.
Worth Mentioning are Mount Unzen (Japan), Mount Etna (Italy), Mount St Helens (USA) and Kilauea (USA).
source : http://www.smashinglists.com/10-most-dangerous-active-volcanoes-on-earth/
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