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Mount Rainier Volcano

 

If you were ever to visit or move to Seattle you would notice the tallest peak in the Cascade Mountains and that is Mount Rainier. Though it looks like a very tall mountain it is actually an active volcano. The Mount Rainier Volcano is the 21st in the list of the most prominent mountains in the world and it stands at 13,211 feet from its low point. It is also the most prominent mountain found in the lower continental United States. From peak of the Mount Rainier Volcano you can actually see another famous volcano in the area which is Mount St. Helens and you can also get a good look at Mount Adams, Glacier Peak, Mount Baker and Mount Hood.

Activity

The Mount Rainier Volcano is what is known as a giant stratovolcano and though it looks quiet it is still considered an active volcano. The last eruption from Mount Rainier took place in 1894 and it has been determined that the volcano has erupted at least a dozen times in 2,600 years. Its largest eruption took place close to 2,200 years ago. Due to the fact that the Mount Rainier Volcano is considered an active volcano there are several smaller high frequency tremors in the area. A lot of times the tremors take place every day. Each month there is a possibility of as many as five quakes taking place at the summit. According to scientists studying the mountain those earthquakes take place due to fluids which circulate inside Mount Rainier.

Craters

The Mount Rainier Volcano has two volcanic craters that overlap at the summit. Each one of these craters is over 1,000 feet around. There is also a small crater lake that can be found and that is 130 feet long and it has a 16 foot depth. This lake is the highest one in the continent when it comes to crater lakes. However, that lake is underneath 100 feet of ice and you can only reach it by going through a network of caves made of ice.

Dangers

The main danger that the Mount Rainier Volcano presents is that it is very close to a highly populated area. The Seattle-Tacoma region could be in grave danger should the volcano erupt again. At the moment scientists do not believe that there will be an eruption anytime soon but that could change as after all it is an active volcano. The population from both Seattle and Tacoma, in addition to the surrounding areas, adds up to close to 3.2 million people and evacuation would present challenges. Another problem is that the volcano is covered with ice. Because of that the USGS (US Geological Survey) has called Mount Rainier “potentially the most dangerous” volcano in the mainland US.

If an eruption took place at the Mount Rainier Volcano the ice on top could create lahars which are a volcanic mudflow that happens when rocks, lava and gas melt ice and create superheated slurry. When an eruption took place 5,600 years ago two of these giant lahars made their way and reached Puget Sound which pushed out the shoreline several miles. That possible danger is what makes Mount Rainier one of only two Decade volcanoes in the US.

Predictions

One of the best tools which geologists and other scientists have to predict volcanic activity is historic data. Unfortunately the Mount Rainier Volcano has not been very predictable. In fact, it could be called erratic for at least 1,000 years. Even so there are few volcanoes in the United States that are more monitored than Mount Rainier. The monitoring of Mount Rainier is done by the United States Geological Survey together with the University of Washington. Any potential hazards from the volcano’s activity will be assessed by those two entities. There are also plans to minimize any population growth in the area wherever it is possible, especially within the hazard zones. A response plan has been developed but due to the vast amount of people in the area it can be hard to put in place.

Facts About Mount Rainier

The name of the Mount Rainier Volcano was given by George Vancouver and it was in honor of Admiral Peter Rainier. There is a Native American name for Mount Rainier and that is Tahoma which means “the mountain that was God.” The peak of the mountain was not reached until August of 1870 by Hazard Stevens and by P. B. Van Trump. The area was designated a National Park in 1899 and every year 2 million people visit the area. Though it looks very close to Seattle it is actually located 87 miles away. Tacoma is a bit closer at only 65 miles and several smaller towns are even closer. Though the volcano is not considered very active at the moment other eruptions in other areas in the world are giving scientists clues about what to expect from Mount Rainier.

Location Map

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Mount St.Helens Volcano

 

Mount St. Helens is found in Skamania County in Washington State and is one of the active stratovolcanoes of the world. Its location in Skamania County puts it 50 miles to the northeast of Portland and 96 miles to the south of Seattle. This volcano is part of the Cascade Range and during the current Holocene period, it has actually been the most active in this range. In addition to being the most active, scientists predict that it is the most likely to erupt of all of the volcanoes found in the United States. The volcano has an elevation of 8,363 feet and contains a horseshoe-shaped crater which developed during its most famous eruption in 1980.

Early History

Mount St. Helens has been active for around 275,000 years during which time it has experienced all sorts of volcanic activity ranging from quiet lava outpourings to violent explosive eruptions. During the previous few thousand years Mount St. Helens finally reached the elevation of 8363 feet (before had 9,677 feet) which made it the fifth tallest peak in Washington. It reached its current height after the eruption in 1980 due to an avalanche.

Volcanologists have divided the volcano’s activity into four stages: Ape Canyon (275 – 35 thousand years ago), Cougar (28 – 18 thousand years ago), Swift Creek (16 – 12.8 thousand years ago) and Spirit Lake (3.9 thousand years ago – present). Because each stage changes the composition of the volcano, destroying evidence of previous stages in the process, more is known about the more recent stages than the older ones.

Semi-Recent Eruptive Periods

The Sugar Bowl Eruptive Period took place between 850 and 900 and during this time, three lava domes developed on Mount St. Helens’ flanks. Despite these additions, there was no significant change to the volcano’s appearance during this period.

The Kalama Eruptive Period took place between 1479 and 1720 and this period is when Mount St. Helens achieved its pre-1980 height and form as around 1,600 feet of elevation were added to the volcano during this period. In the beginning of this period there were two large and explosive eruptions which took place in the years 1479 and 1482, a rare phenomenon as those dates are very close together. The early part of this period also produced many pyroclastic flows and lahars. The middle phase began around 1510 and during this point there were few lava flows but many pyroclastic flows. The Summit Dome grew during the late phase of the Kalama Period at Mount St. Helens and most likely took around 100 years to be created.

The Goat Rocks Eruptive Period at Mount St. Helens took place from 1800 to 1857 and this is when the Floating Island, a lava flow in 1801, was created. Scientists believe that the last significant eruption during this period (and in fact until 1980) took place in 1857 although there minor explosions in 1898, 1903 and 1921.

1980 Eruption

The eruption of Mount St. Helens in 1980 is probably the most well-known for this volcano. The first eruption in that group occurred on March 27th and was the first in more than 100 years. Eruptions continued, occurring about once an hour during March and going down to about once a day by the 22nd of April. Eruptions then paused until May 7th at which point small eruptions occurred until the 17th. Mount St. Helens had experienced over 10,000 earthquakes, causing the north flank to grow about 250 feet. This bulge kept growing, indicating a pool of magma that would erupt in the future.

The magnitude 5.1 earthquake mentioned above occurred on May 18th at which point both the summit and the northern bulge became a large landslide. This was in fact the largest avalanche of debris ever recorded in Earth’s history with a total volume of around 3.3 billion cubic yards. The landslide removed the northern flank of Mount St. Helens which in turn triggered a huge lateral blast of hot debris that traveled at around 300 miles per hour. The change in pressure caused a 9 hour long eruption that included a tall eruption column as well as many pyroclastic flows and a great deal of ash fall. The eruption also created lahars (volcanic mudflows) when the snow and ice that had topped the volcano melted and mixed with the volcanic debris.

Mount St. Helens – Future Eruptions

Although this volcano is the most likely one in the Cascades to erupt again within our lifetime, experts do not believe it will be as damaging as the eruption of 1980. They do not think that a lateral blast or such a large avalanche of debris is likely. The main hazards for renewed activity on the volcano are lahars, explosive eruptions causing pyroclastic flows and a continuation of the growth of the lava-dome. Because scientists are not able to predict the next eruption very far in advance, they are keeping close tabs on the volcano using a wide range of geological equipment.

Location

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Mount Vesuvius Volcano

 

Mount Vesuvius is one of the most well-known volcanoes around the world with most of its fame coming from its eruption in 79 A.D. that completely buried the city of Pompeii. The volcano is located in Italy in the Gulf of Naples and is one of the volcanoes making up the Campanian volcanic arc. This volcano is in fact the only volcano located in Europe’s mainland that is active and measures at 1,281 meters tall.

Plate Tectonics

As mentioned above, Mount Vesuvius is one of the volcanoes found in the Campanian volcanic arc. Some of the others volcano also found in this arc are Stromboli, Vulcano, Campi Flegrei (Phlegraean Fields) and Mount Etna. These volcanoes are all part of the same subduction zone which was created by the Eurasian and African tectonic plates converging.

First Recorded Eruption

One of the main reasons Mount Vesuvius is so famous is that it is actually one of the first volcanoes to have an eruption described in detail. During the eruption in 79 A.D., Pliny the Younger saw the volcanic eruption from his location in Misenum, around 18 miles away. A short time later, he wrote about what he saw, giving us an early written record of volcanic eruptions. He described the eruption as a large cloud resembling a tree, complete with a trunk and branches of smoke and ash. Pliny the Younger is actually the namesake of the term Plinian which geologists use to describe eruptions that are similar to the one in 79 A.D. in that they are violent and produce a large volume of quickly-expanding gases, ash and rock.

The eruption Pliny the Younger saw occur in 79 A.D. is the famous eruption that completely covered the cities of Pompeii and Herculaneum. Historians estimate that this eruption may have killed over 16,000 people. The main cause of death during this eruption was due to suffocation on the volcanic ash. The most interesting part about this famous Mount Vesuvius eruption is that due to the hot ash in the air, casts were formed which preserved the deceased in great detail. The only hints that the eruption was to come were a few days before when the underground water sources ran dry and a minor earthquake occurred.

Sunset at Pompeii
Vesuvio volcano, Italy.

Volcanic Activity

In the previous 17,000 years, Mount Vesuvius has had 8 major eruptions, including the one in 79 A.D. Around 3,780 years ago, the Avellino eruption occurred which not only caught the residents of surrounding areas by surprise but was powerful enough to cause the surrounding area (thousands of miles of it) to become desert for over 200 years.

Immediately after the eruption in 79 A.D., the volcano erupted around every 100 years until 1037, at which point it temporarily stopped. This long period of quiet caused its eruption in 1631 to kill 4,000 people in the area.

More recently Mount Vesuvius erupted on April 7, 1906, the eruption which ejected the highest amount of lava ever to be recorded from this volcano. This eruption killed 100 people and completely changed the plans for the Summer Olympics of 1908. The most recent major eruption occurred on March 18, 1944 and destroyed several nearby villages, killing 26 people.

The Volcano Today

Mount Vesuvius and its surrounding area is a national park and is open to visitors. There are several paths around it including access to the summit. Despite the imminent eruption, visiting the site should be safe as scientists expect to have warning prior to the next eruption.

Today there are 18 towns found around the base of Mount Vesuvius and together these contain 600,000 people, all living within the red zone. This zone is in the direct line of fire in case an eruption occurs and would see most of the damage.

What Would Happen In An Eruption?

Scientists have measured that Mount Vesuvius currently sits on top of a larger layer of magma that lies deep inside the earth and is 154 square miles, which is a very large amount of magma compared to other volcanoes around the world. In addition, scientists believe that the next eruption, like the one in 79 A.D. will be a Plinian eruption, meaning that it can contain flying ash and rock that reaches speeds of around 100 mph. Because of its proximity to Naples and the large number of people living nearby, an eruption could put over 3 million people at risk.

Due to new technology, the Italian government hopes to have two weeks to 20 days warning before the next eruption, hopefully providing enough time to put their evacuation plan into effect and save all of the people living in the area. Despite this, they are aware of the dangers for the people around the volcano and have offered to pay them to move out of the area, although few people have taken them up on their offer.

Location

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Pacific Ring Of Fire Facts

 

The Pacific Ring of Fire is the name that is given to a horseshoe shaped area in the Pacific Ocean which extends from South America and North America to Eastern Asia, Australia and New Zealand. This area is famous for its constant seismic activity and because of the amount of active volcanoes that can be found here. 75% of dormant and active volcanoes are found in the Pacific Ring of Fire. Now it is known that the area is very close to several tectonic plates which may be what influences the violent activity in the area.

Volcanoes In The Area

It is believed that the Pacific Ring of Fire has a total of 452 volcanoes. Some of the world’s most active volcanoes are found here. Kilauea which is considered the most active volcano in the world is located in the Pacific Ring of Fire. Other volcanoes worth noting are Mt Fuji in Japan, Mt. Saint Helens and Mt. Rainier in the American North West, Krakatoa in Indonesia, Mauna Loa in Hawaii, Galeras in Colombia and Sangay in Ecuador. Those are all volcanoes that are well known and some that could be very dangerous to the population nearby.

Most Dangerous Volcanoes

Because of all the activity in the Pacific Ring of Fire it is very possible that one of those volcanoes could cause a lot of trouble for a lot of people. If Mt Rainier were to erupt for example the 2.5 million people in the area near Seattle and Tacoma would have to evacuate fast. Adding to the danger is the snowy cap of the volcano which could make the dangers much worse.

The Santa Maria Volcano in Guatemala has already shown its power with one of the most catastrophic eruptions in the 20th century taking place in 1902. Back then the volcano affected a very large part of the south west of the country; today with many more people in the area the impact of this volcano in the Pacific Ring of Fire could be much greater.

Mount Yasur in Vanuatu is what’s called a stratovolcano and it has been erupting for close to a hundred years. The dangers that Mount Yasur presents are real, and yet tourists risk the dangers of toxic gases and lava flows by getting to the crater every day. This volcano has already taking a few lives from tourists and a tour guide who got too close to the danger zone.

Constant Changes

The Pacific Ring of Fire is different today than it was thousands of years ago because of the changes caused by tectonic plates. The Pacific Plate will hit other plates nearby and that causes them to sink. The crust melts producing the magma that feeds the different volcanoes in the Pacific Ring of Fire or it will help produce new volcanoes. The tectonic plates are also the reason for the many violent earthquakes in the entire area of the pacific.

Risks

If you are in a city that is located in the Pacific Ring of Fire then you already know that there are several risk factors that you have to be ready for. Close to 90 percent of the earthquakes reported around the world take place in the Ring of Fire. Add to that the possibility of volcano eruptions and that can really be a dangerous area to live in. People not only have to look at the active volcanoes as the dormant ones also pose a threat. Mt. Saint Helens was a dormant volcano before its eruption in 1980 which caused several deaths and over a billion dollars in damage.

 

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Shield Volcano Facts

 

A shield volcano resembles the appearance of a Hawaiian warrior’s shield in that they have a low-angle profile. In almost all cases the comparison to a shield is done because the width of these volcanoes is typically around 20 times the size of their height. Despite this, they can vary greatly in terms of size with some having small diameters of a few kilometers while others can be over 95 kilometers. Some located in Hawaii reaching an altitude of 8,000 meters above the sea floor, which is 12,000 meters above their base. In fact, some of the largest volcanoes you will find on the planet are actually shield volcanoes, with Mauna Loa, located on Big Island in Hawaii, being the largest of this type.

Formation

A shield volcano is most likely to form during a lava flow of fluid basaltic material, usually those that flow down from either a flank fissure system or the summit itself. The most common type of shield volcano is those that form during one long-term eruption. Some shield volcanoes, however, are pyroclastic shields meaning that their low-angle slopes have been formed from the accumulation of fragmented material over the course of several eruptions.

Because of the variety of formation, you will see slightly different shapes in the various shield volcanoes around the world. The ones in Iceland, for example, are generally much smaller in size and almost perfectly symmetrical while those found in Hawaii are much larger (think of Mauna Loa) and elongated. The shields found on the Galapagos Islands are different from both of these, having flat tops, steep middle slopes and deep calderas at the summit. These differences not only show variations in formation but also in the eruption types generally found in the region.

Eruptions

Although the type of eruptions found in a shield volcano can vary slightly, most experience Hawaiian eruptions. These eruptions will usually have ground flows of lava that is capable of traveling great distances. Because the flows travel a longer distance, the individual sheets of lava are generally thinner. These longer lava flows from the eruptions are what gives the shied volcano their distinctive shape.

Hawaiian Volcanoes

Hawaii is home to a great deal of the planet’s shield volcanoes as the Pacific Plate and the Hawaii hotspot have combined to form a large chain of various volcanoes of all types. This chain includes more than 43 major volcanoes, including Mauna Loa. As mentioned earlier, Mauna Loa is the largest shield volcano. It is also Hawaii’s highest volcano, reaching 4,170 meters above sea level in addition to traveling 13 kilometers down below the waterline. This volcano has most likely been eruption for over 700,000 years and the most recent eruption took place in 1984.

Mauna Kea is another shield volcano found in Hawaii and it has an altitude 4,205 meters above sea level and from its base below sea level it is 10,200 meters. This means that although Mauna Kea has a higher elevation than Mauna Loa, its total height is smaller. Mauna Kea is probably around a million years old, attributing to its steeper and smoother profile. Despite this, this shield volcano has experienced several explosive eruptions late in its life which created several cinder cones on its summit.

Another one of Hawaii’s shield volcanoes is Kilauea which is in fact the most active of the island’s volcanoes. This volcano is only between 300,000 and 600,000 years old, making it one of the youngest in the area. At first scientists actually thought Kilauea was part of Mauna Loa; however they have since discovered that it acts independently. Interestingly enough, Kilauea’s current eruption began on January 3, 1983, meaning it has been going on for 30 years to date.

Iceland

Another place that you can find multiple shield volcanoes is in Iceland. The shield volcanoes found there usually range from 5,000 to 10,000 years old. These volcanoes are also usually smaller than those in other locations and are generally symmetrical and their eruptions usually occur from their summit calderas.

Galapagos Volcanoes

Another area with a great deal of shield volcanoes is the Galapagos Islands, with the volcanoes ranging from 700,000 to 4.2 million years old. Several of the islands are in fact shield volcanoes, such as Fernandina. This shield volcano has steep upper flanks but low-angle lower flanks. It has been currently erupting since April of 2009.

In terms of composition, the lava flows found in the Galapagos Islands are very similar to those in Hawaii although unlike other sets of volcanoes formed by one hotspot, they do not create a line.

Other Volcanoes

In the Auckland volcanic field in New Zealand you can find Rangitoto which actually forms its own island with a width of 5.5 kilometers. This volcano erupted around 550 years ago. In the United States, you can find the Belknap volcano in the Cascade Range in Oregon in addition to the Newberry volcano which takes up around 1600 square kilometers of land.

 

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Stratovolcano

 

Stratovolcanoes, or composite volcanoes, are similar to cinder cone volcanoes in terms of their shape, but that is one of their few similarities. These volcanoes have gentle lower slopes but much steeper upper slopes, creating an upwardly concave cone and generally have many distinct vents. The summit crater of these volcanoes is usually relatively small.

Despite their general shape, there are some variations within stratovolcanoes due to various composition and types of eruptions. For example some of these volcanoes may have features such as calderas or amphitheaters due to past lateral blasts, such as you can see with Mount St. Helens.

These volcanoes generally take between tens of thousands and several hundred thousand years to form. Most of the stratovolcanoes in the world that are currently active are less than 100,000 years old but some are much older, possibly over a million, such as Mount Rainier.

Eruptions

Stratovolcanoes are one of the most deadly types of volcanoes and their most common type of eruption is Plinian, which is highly explosive and dangerous. These eruptions will generally produce pyroclastic flows containing toxic gases and hot volcanic fragments that move at very fast speeds. Stratovolcanoes can erupt any variety of magma types with levels of basalt, andesite, dacite or rhyolite, but most of the time the lava cools and then hardens before it spreads very far, meaning that they will generally have a narrower base than other types, such as shield volcanoes. Unlike several other types of volcanoes, a stratovolcano usually has a large rest between eruptions.

Chilean Andes

Nevado Ojos del Salado is the highest volcano on earth. This Chilean stratovolcano rises to 6,887 meters above sea level. Close to it, also in the Chilean Andes, is Llullaillaco which is the tallest volcano to have eruptions in recorded history, measuring 6,739 meters. Nevado Ojos del Salado has a crater lake at around 6,390 meters above sea level, which is one of the highest lakes in the world, if not the highest. Scientists believe that the most recent eruption took place about 1,300 years ago, but are not positive. There is a possibility that the volcano emitted a small bit of ash in 1993 which would make it historically active and the tallest historically active volcano instead of Llullaillaco.

Llullaillaco is actually right on Chile’s border with Argentina. This stratovolcano is made up of a younger volcano that developed on top of an older one whose upper area collapsed around 150,000 years ago. The younger volcano began developing around 10,000 years ago.

Mount St. Helens

Although Mount St. Helens has the title of one of the youngest stratovolcanoes located in the Cascades, it is the most active. Just within the last 3,500 years, at least 35 layers of tephra have been created by its eruptions. This stratovolcano is most well-known for its eruption in 1980 which killed 57 people in addition to destroying 185 miles of highway, 15 miles of railways, 47 bridges and 250 homes. This eruption was triggered by a 5.1 earthquake and created an avalanche of debris that had a volume of around 0.7 cubic miles.

Mount Rainier

Mount Rainier is the tallest peak of the Cascade Range and measures in at an elevation of 4,392 meters. Although Mount Rainier itself has developed within the last half a million years, between one and two million years ago there was a similar cone in its place. An eruption that took place 5,600 years ago created a large crater at its top but this was later filled when the summit was rebuilt by later eruptions. Although the most recent magmatic eruption of this stratovolcano took place around 1,000 years ago, it has had several dozen highly explosive eruptions since the previous ice age which have spread tephra all across the state of Washington.

Krakatoa

Krakatoa is a volcanic island located that is part of the Sunda Strait. In 1883 this stratovolcano had a series of violent eruptions which sent ash flying more than 50 miles into the atmosphere in addition to being heard at least 2,200 miles away from its location. The large release of energy from its eruption caused tsunamis which in turn took the lives of 36,400 people on Sumatra and Java.

Tambora

Tambora is an Indonesian stratovolcano that erupted in 1815. In fact, these eruptions were so violently explosive that they are one of the largest in the entirety of recorded history. When the volcano erupted, the global temperatures dropped around three degrees Celsius, which is no surprise as ash was ejected 50 kilometers into the atmosphere. Because the stratovolcano erupted so much material, it caved in after the eruption was complete and in the process created a caldera that is large enough to be visible from space.

 

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Subglacial Volcano

 

A subglacial volcano is a volcano that is located either underneath a glacier itself or under the water in a lake which is inside a glacier. These volcanoes are very different from the other types in terms of shape as they usually have steep sides and a flat top. The exception is in the cases when the subglacial volcano produces enough heat to melt the ice layer above it, in which case its shape will be more conventional.

Because of their proximity to glaciers, these volcanoes are most common in Antarctica and Iceland although some older volcanoes can be found in Canada as well. These volcanoes can be very beautiful due to the snow and ice; however, these features make them very hard to access.

Eruption

Usually when a subglacial volcano erupts the heat associated with the flow of lava will cause the overlying ice to melt. When this happens, the water cools the lava very quickly in a manner similar to what happens with a submarine volcano and will therefore produce a flow with pillow shapes similar to an underwater eruption. With these eruptions however, the pillows will break off and fall down the slopes of the volcano, causing a formation of hyaloclastite, tuff breccia and pillow breccia (breccia is a type of sedimentary rock). Because of the water present during a subglacial volcano eruption, they can also produce lahars and dangerous floods.

Jökulhlaup

A jökulhlaup is an outburst flood that is produced from a glacier. They are most commonly associated with a subglacial volcano and will occur when the heat from the eruption causes the surrounding glacier to melt, creating the flood. Although the term originated in Iceland to describe this occurrence in relation to their volcanoes, it is now used by geologists around the world. A classic example of a jökulhlaup is when Katla in Iceland erupts, it causes the glacier Mýrdalsjökull to experience this phenomenon.

Antarctica

The most popular locations in the world to find a subglacial volcano is Antarctica. This is because volcanoes in this area can be found spanning around 5000 kilometers, going all the way from East Antarctica to the Antarctic Peninsula and all the way to the South Sandwich Islands which are sub-Antarctic. Because of the large quantity of volcanoes combined with the cold environment and presence of glaciers, it is no surprise that the area is home to a large proportion of the subglacial volcano population.

A subglacial volcano in Antarctica that was only recently discovered is actually over 20,000 square miles. Scientists believe that this volcano erupted over 2,000 years ago and the heat from the eruption actually created a hole in the ice sheet. They also believe that this volcano probably produced a large plume of gas and ash that reached 8 miles in the sky. The combination of factors leads the scientists believe that the eruption of this volcano was the largest eruption that took place in Antarctica within the previous 10,000 years.

The most interesting thing about this volcano is that it most likely still active, making scientists wonder what would happen to the surrounding glaciers if it were to erupt again.

Iceland

Due to its cold environment and large number of volcanoes, Iceland is another place to find these subglacial volcanoes. In fact, in 2010 the subglacial volcano Eyjafjallajökull began erupting after 200 years of being dormant. There is another similar volcano nearby named Katla, whose eruption from one of its fissures in 934 A.D. created one of the largest known lava flows to take place during the Holocene. Although this volcano was more active in historical times than at present, there is still occasional small activity.

 

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Photo taken by: United States Geological Survey

Kilauea Volcano Facts

 

The Kilauea Volcano is the youngest volcano on Hawaii’s Big Island. Because when viewed from above it seems tiny in comparison to the neighboring volcano Mauna Loa, Kilauea was originally believed to simply be a satellite of Mauna Loa instead of a distinct volcano. Research that has taken place during the last decades, however, shows that not only is Kilauea a separate volcano, but its magna-plumbing system actually goes over 60 kilometers deep into the earth. The Kilauea Volcano sits on a curved line made up of other volcanoes such as Kohala and Mauna Kea.

Description

The highest point on the Kilauea Volcano is slightly less than 4,200 feet. In addition, it has a large caldera at the summit that is 3 kilometers by 5 kilometers wide at the main depression but is 6 kilometers by 6 kilometers at the outermost faults and goes down 165 meters deep. The entire area of the volcano is 552 square meters. The oldest rocks found on the volcano date back 23,000 years and scientists estimate that the first eruption occurred between 300,000 and 600,000 years ago. Despite this, about 90% of the basaltic shield volcano found on the surface is made from lava flows that occurred less than 1000 years ago while 70% of the actual volcano’s surface is 600 years old or younger. The volcano gets its name, Kilauea, from the Hawaiian word meaning much spreading or spewing, referencing the frequent lava flows.

Nearby Wildlife

Because of the constant activity of the Kilauea Volcano, there are semi-frequent acid rains in the nearby Ka’u Desert, a barren region to the south of the volcano’s southwestern rift zone. Despite this, wildlife still manages to flourish in several nearby areas, especially those that are more or less undisturbed by the volcanic activity. In the Hawaii Volcanoes National Park, which contains most of Kilauea’s southern ecosystem, you will find a wide range of bird species in addition to several endangered species of sea turtles.

Eruption History

In addition to being the youngest volcano on Hawaii’s Big Island, the Kilauea Volcano is actually the most active of the state’s volcanoes in recent years; in fact it is one of the most active volcanoes on the entire planet. The volcano has been present in many Polynesian legends and it has been almost constantly active since the first recorded eruption which occurred around the year 1750. Most of the volcanic activity at Kilauea between 1750 and 1924 was smaller and originated in the lava lake found at the summit. In 1924, however, the volcano had an explosive eruption and from then to 1955 there was a period of short eruptions.

Current Eruption

Impressively enough, the current eruption of the Kilauea Volcano, named Pu’u O’o started 30 years ago! It began on January 3, 1983 at which point ground fissures opened and thin streams of molten lava appeared from a 7 kilometer long fissure. Throughout the course of the current eruption, the main exit point of the lava has shifted several times. It spent the first 3.5 years erupting from a central vent but in July of 1986, it suddenly moved down the rift 3 kilometers to the Kupaianaha shield, where it stayed until early 1992. When the eruption point changed, so did the style, shifting from high fountaining occurring in episodes to a continuous but quiet effusion in a lava pond.

In November of 1986, lava from this eruption point met the ocean at a point 12 kilometers away and covered Kapa’ahu along the way. The most destructive phase of the Kilauea Volcano’s current eruption began in 1990 when its lava flows flooded Kalapana, a nearby village where it destroyed more than 100 homes in just 9 months. The lava flow declined throughout 1991 but in 1992, eruptions began once again. Now lava flows usually come through the lava tubes and go into the ocean and there are few surface flows.

Throughout the current eruption, lava flows have varied greatly, ranging from 300,000 to 600,000 cubic meters each day and there were actually 24 days during early 1997 in which there was no eruptive activity.

Research And Preservation

At the rim of the Kilauea Volcano you will find the Hawaiian Volcano Observatory, which was founded in 1912 by Thomas Jagger and this is where most of the research on the volcano takes place. In addition, the Hawaii Volcanoes National Park was created in 1916 by Woodrow Wilson. This began the area’s path towards becoming a World Heritage Site.

Tourism

The first hotels appeared around the rim of the Kilauea Volcano in the 1840s. After the area became a National Park in 1916, tourism continued to increase greatly. Today around 2.6 million tourists visit the volcano and surrounding areas each year, mostly due to its location in beautiful Hawaii combined with its active yet docile nature.

Location

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Mud Volcano

 

A mud volcano is a formation that was created by any geo-excreted gases and liquids and the formation process can vary slightly. This type of volcano is usually found in subduction zones and around the world, many have been recognized. Most of the gases that are released from a mud volcano are methane although they also release much smaller quantities of nitrogen and carbon dioxide. Generally the ejections from these volcanoes will be fine solids which are suspended in liquids that can include acidic water.

These volcanoes have been identified all around the world including United States, Canada, Taiwan, Italy, Iran, India, Pakistan, Romania, Burma, China, Indonesia, Japan, Colombia and Venezuela just to name a few countries. Most, however, appear in Eastern Azerbaijan. Scientists think there may even be a few on Mars.

Structure

As mentioned earlier, it is more likely to find a mud volcano near a subduction zone, but they are also common near petroleum deposits. It is also possible to find them near other types of volcanoes. This type of volcano has a similar shape to other types of volcanoes and contains several cones. The gryphon is cone with steep sides that is shorter in height than 3 meters and will emit mud while the mud cone is less than 10 meters and will emit both rock fragments and mud.

A mud volcano can also contain scoria cones which form when the mud is heated during fires. In general these volcanoes never grow as large as other types as the largest have a height of around 700 meters and a diameter of around 10 kilometers.

Emissions

As mentioned above, when a mud volcano is by itself, the main gas it emits is usually methane, but in cases when they are located near to other volcanoes they will usually emit incombustible gases such as helium instead. Although most of the material is emitted during eruptions, some seeping can take place even when the volcano is dormant.

Formation

There are several different models for the formation of a mud volcano but the easiest to understand is the following. The process begins when decompaction occurs (the opposite of compaction) which will create gases at a high rate. The gases cause the mud to become buoyant and because there is more pressure by the mud than there is outside of the forming mud volcano, the mud leaves the structure via vents or fractures and takes some of the gas with to relieve the pressure.

Azerbaijan

Azerbaijan has the largest concentration of mud volcanoes with at least 400, 200 of which are within a range of few thousand square kilometers. Some of the volcanoes in this area have created islands, both permanent and temporary, in addition to submarine banks.  Some of the largest of this type of volcano are actually found in Azerbaijan and are Turaghai and Boyuk Khanizadagh. In 2001, a mud volcano only 15 kilometers from Baku, the capital, erupted, shooting flames that reached 49 feet in the air.

Indonesia

One of the most famous mud volcanoes is Lusi located in Indonesia. When this mud volcano first showed activity in May of 2006 it killed 14 people and displaced 25,000. Five years after the eruption began, it was still going on and scientists predicted it would continue for 25 more years. The volcano has continually spewed mud and gases and as of 2001, it had already emitted millions of cubic meters of muddy liquids, reaching an emission up to 180,000 cubic meters of mud per day.

Scientists are unsure what caused the volcano to begin erupting. Some believe that the previous 6.3 earthquake (which occurred 2 days before at 280 kilometers away from the site) triggered it while others believe there was an explosion underground which triggered it.

 

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Submarine Volcano

 

A submarine volcano is different than all of the other types because they are found underwater. These volcanoes are in fact some of the most productive of the volcanic systems, producing around three quarters of the year’s output of magma but most people do not think of them because they are usually located around 8,500 feet underwater on average. Some scientists estimate that in the Pacific Ocean in just a million square kilometers of the ocean floor you will find around 4,000 volcanoes. Like other types, a submarine volcano can vary greatly in height, although it is estimated that around 75,000 of those in the Pacific Ocean rise half a mile over the ocean floor.

Eruptions

Although each submarine volcano is located underwater, it will still produce eruptions while active and the products of these eruptions are what shape the way the sea floor looks. Scientists estimate that out of the million or so of these volcanoes that can be found around the world, many thousands of them are active. Despite this because of their location underwater, it can be hard to catch a submarine volcano in the eruption process. However, scientists do know that most eruptions from these volcanoes will take place in shallow water although recent technological advances have helped scientists document those that take place in deeper water well.

Deposits

Because a submarine volcano is located underwater, the deposits that are created during the eruption can be very different than those of other types of volcanoes. Volcanologists are actually unsure if an explosive eruption of a submarine volcano is even possible. That is because due to the high pressure created by the water (250 times the atmospheric pressure) bubbles are hard to form in the magma and lava. Because the water will almost instantly quench the lava, the outer surface of volcanic flows becomes glass.

Lava Flows

The shape of the flows of a submarine volcano tends to be pillow-like as compared to the blocky flows that are typical of land volcanoes. These pillows are created when the crust of a flow will split causing the lava to ooze out at which point it flows a very short distance and solidifies. The process then repeats with the new piece of lava and ends up creating what seems to be a large stack of pillows. The lava flows can also take other shapes, such as sheet flows and tumuli, which is an inflation feature.

Volcanic Ecosystems

Like all volcanoes, a submarine volcano is associated with a unique volcanic ecosystem. These are usually located by hydrothermal vents, or black smokers, which have been located at all of the mid-ocean ridges around the world. At these vents, hydrogen sulfide and water in addition to other minerals exit these vents, creating an ecosystem of organisms that live using sulfur instead of sunlight. Here you can find tube worms, mussels, giant clams and other organisms.

Detection Of Eruptions

As mentioned earlier, despite recent advances in technology it is still difficult for scientists to detect the eruption of a submarine volcano. In fact, they have only been capable of detecting them at all since around the year 1990. Long before they were first detected, oceanographers and volcanologists alike were aware that submarine volcano eruptions were occurring but had no way to know where and when. In recent decades, however, they created a new system that measures the small earthquakes that are normally part of magma migration.

Instead of relying on feeling vibrations like they do with earthquakes on land, this system listens for them as the vibrations underwater will produce an acoustic wave. Since this system was created, it has been much easier for scientists to pinpoint the location of these underwater eruptions.

 

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