Monday, 18 July 2011

Large Earthquakes Trigger A Surge In Volcanic Eruptions

In 2012 there will be fire raining from the skies, tsunamis, bringing civilisation to its knees. 


Is this possible, it is clear that the planet is going through unprecedented change, could this be the prelude to fire raining down from the skies? Mountains falling into the seas?

A study carried out by Oxford university showed that there is a direct link between earthquakes and volcanoes erupting.

It is interesting that in recent years there has been an increase in earthquakes, extreme weather, solar activity, etc. As we get closer to 2012 will these earth changes become even more dramatic?

There are a lot of dangerous volcanoes that could erupt at anytime, such as:
Italy's Mount Vesuvius is most famous for the A.D. 79 eruption that buried the cities of Pompeii and Herculaneum. Despite the dark history, millions of people today live near the volcano. The thriving mass of humanity in such close proximity to the volcano makes Vesuvius a serious contender for the world's most dangerous volcano. Scientists fear that a catastrophic eruption could hurl scalding gas-rich magma, water vapor and debris at the masses with insufficient warning time for an evacuation. 
After 9,000 years of dormancy, the Chaiten volcano in southern Chile awoke in 2008 and began a series of eruptions that spewed ash miles into the sky, as shown in this image. The volcano's namesake town of 4,500, just 6 miles from the spewing crater, was devastated by falling ash and floods. The eruption claimed at least one life and serves as a stark reminder that slumbering volcanoes pose grave dangers. Click on the "Next" label to learn about seven more dangerous volcanoes around the world. 
Mexico City, a metropolis of 18 million people, sits 40 miles to the east of Popocatepetl, the second tallest volcano in North America. Puebla, a town of 2 million, lies 30 miles to the west. A major eruption, scientists say, could choke the skies with ash and send massive mudslides into the crowded valleys below. The result could prove catastrophic. The volcano has been relatively quiet since a bout of activity between 1920 and 1922, though it rumbled back to life in 2000, as shown in this image, prompting evacuation orders and worries that "Popo" is ready to blow. 
Merapi in Indonesia is one of the world's most active volcanoes, regularly spewing hot gas and ash miles into the sky, and sending mud and fragmented rocks down the sides. In 1994, 60 people were killed by a searing gas cloud, and about 1,300 people died when it erupted in 1930. During a bout of eruptions in 2006, many villagers, including the woman in this picture, refused orders to evacuate. They believe the spirits will warn when a catastrophic eruption is imminent. 
Lava flows, while hot, are rarely deadly: They usually ooze slow enough that people can easily outrun them. That's not the case with the lava that flows from Nyirangongo in Africa's Democratic Republic of Congo. It has very low levels of silica, the mineral that thickens and slows lavas. In 2002, Nyirangongo's lava suddenly gushed at speeds up to 60 mph into the town of Goma, which is home to half a million people. Scientists fear that lava pooling in the crater could suddenly drain again and cause even more devastation. 
After nearly a year of minor earthquakes and eruptions, Colombia's Nevada del Ruiz volcano exploded on Nov. 13, 1985. Pyroclastic flows melted the summit's snowcap. Mudflows, called lahars, raced down the mountainside. One mudflow wiped out the village of Chinchina and killed 1,927 people, according to reports. A second followed the same path as earlier lahars and swept away the town of Armero, shown in this image. An estimated 23,000 people died, making it Colombia's worst natural disaster. Scientists said an early warning system could have averted the loss of life. Now that one is in place, will it work when the volcano wakes again? 
The islands of Japan harbor more than 100 volcanoes, and a handful or so erupt every year. The majestic Mount Fuji, shown here, has not erupted since 1707, but a swarm of low-frequency earthquakes in 2000 and 2001 raised the specter that the mountain was awakening from its 300-year slumber. Though Fuji has since quieted down, the risk to Tokyo, a city of 30 million people just 70 miles to the east, is very real, scientists say. A 2004 government study put the price tag of a worst-case eruption at more than $20 billion. 
Washington's 14,410-foot-tall Mount Rainier, shown in this image, is a big attraction for many people in the Pacific Northwest. It is also a big threat, according to scientists. An estimated 3 million people live in its shadow — at least 100,000 on top of old mudflows from previous eruptions. The flows, known as lahars, are the greatest risk. Though commonly associated with major eruptions that strike with ample warning, an earthquake or small burp of rock, ash and gas could also trigger a lahar, giving residents in the path only 10 to 15 minutes to escape. 
Yellowstone Park Volcano. 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. 
 

April 2011 - YELLOWSTONE has 4.1 magnitude earthquake


video
Yellowstone is an active volcano, however there has been an increase in earthquakes in and around the area over the last few years. If the the Oxford University findings are correct, earthquakes trigger volcanic eruptions, then Yellowstone may be on the verge of a catastrophe. The only question is why hasn't it happened yet?

Large Earthquakes Trigger A Surge In Volcanic Eruptions 
ScienceDaily (Jan. 12, 2009) — New evidence showing that very large earthquakes can trigger an increase in activity at nearby volcanoes has been uncovered by Oxford University scientists. 
An analysis of records in southern Chile has shown that up to four times as many volcanic eruptions occur during the year following very large earthquakes than in other years. This ‘volcanic surge’ can affect volcanoes up to at least 500 km away from an earthquake’s epicentre. 
A report of the work will be published in the journal Earth and Planetary Science Letters.
Previously, scientists had identified a few cases where volcanic eruptions follow very large earthquakes – but up until now it had been difficult to show statistically that such earthquakes may be the cause of an increase in eruptions, rather than the events just being a coincidence. 
‘The most unexpected part of this discovery was the considerable distance from the earthquake rupture where these eruptions took place, and the length of time for which we saw increased volcanic activity,’ said Sebastian Watt, a Dphil student in Oxford’s Department of Earth Sciences, who conducted the analysis. 
‘This suggests that seismic waves, radiating from the earthquake rupture, may trigger an eruption by stirring or shaking the molten rock beneath volcanoes. The disturbances that result from this lead to eruption but, because of the time it takes for pressure to build up inside a volcano and for magma to move towards the surface, an eruption may not occur until some months after the earthquake,’ Sebastian added. 
Sebastian examined the volcanic eruption and earthquake records of southern Chile – where, in 1835, Charles Darwin first speculated on the link between earthquakes and eruptions. By careful analysis of historical records, he discovered that volcanic activity increased for about a year after each of the very largest earthquakes in southern Chile during the past 150 years. The volcanoes most likely to be affected lay within about 500 km of the earthquake epicentre, and included both dormant and active volcanoes. 
The great Chilean earthquakes in 1906 and 1960 (the largest earthquake ever recorded) were each followed by activity at six or seven volcanoes – a significant increase on the average eruption rate of about 1 per year. Sebastian said: ‘This work is important because it shows that the risk of volcanic eruption increases dramatically following large earthquakes in parts of the world, such as Chile, affected by these phenomena. Hopefully, our findings could help governments and aid agencies in these regions to manage volcanic hazards by showing the need for increased awareness of volcanic activity after large earthquakes.’
source: http://www.sciencedaily.com/releases/2009/01/090110084653.htm




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