Small quakes reported near Old Faithful

[katatonically]

Wed Oct 25, 2006 6:53 am (PST)
YELLOWSTONE NATIONAL PARK, Wyo. - A swarm of more than 70 small
earthquakes shook the ground near Old Faithful geyser earlier this
month. The largest was a magnitude 2.4, barely enough to be felt. The
swarm of 74 quakes lasted several hours Oct. 14, according to
information released by the Yellowstone Volcano Observatory.

The tight cluster of earthquakes was moderate compared with others in
Yellowstone' s past, including one in April 2004 in which more than 400
earthquakes were recorded over three days.

"It piques our curiosity, but it's not out of the range of normal
behavior," Henry Heasler, Yellowstone' s principal geologist, said of the
Oct. 14 activities.

Park officials said the earthquakes were more likely caused by the
underground movement of hot water and gas, rather than the migration of
magma.

The largest swarm recorded in Yellowstone was in the fall of 1985 when
about 1,800 earthquakes were registered, ranging in magnitude from 1 to
4.9. Around the same time, the huge Yellowstone caldera stopped slowly
rising and began slowly falling.

___

http://news. yahoo.com/ s/ap/yellowstone _quake_swarm

On the Net:

Yellowstone Volcano Observatory: http://volcanoes. usgs.gov/ yvo/

 

[the_hammer]

Saw a programme on TV about a year or two ago about super volcano's. I think it was on the Discovery Channel. They predicted that the most likely place for a super volcano to erupt was in the Yellowstone National Park.

Found this link when looking for super volcano's: http://armageddononline(dot)tripod.com/volcano.htm
This page says pretty much the same thing as they said on the programme.

What is a super volcano?
A super volcano is the most destructive force on this planet. Only a few exist in the world and when they erupt they do so with a force tens of thousands of times greater than other eruptions. They lie dormant for hundreds of thousands of years as a vast reservoir of magma builds up inside them before finally they unleash their apocalyptic force, capable of obliterating continents. They threaten the survival of mankind.

What happened during the last eruption of a super volcano?
The last eruption of a super volcano was in Toba, Sumatra, 75,000 years ago. It had 10,000 times the explosive force of Mount St. Helens and changed life on Earth forever. Thousands of cubic kilometres of ash was thrown into the atmosphere - so much that it blocked out light from the sun all over the world. 2,500 miles away 35 centimetres of ash coated the ground. Global temperatures plummeted by 21 degrees. The rain would have been so poisoned by the gasses that it would have turned black and strongly acidic. Man was pushed to the edge of extinction, the population forced down to just a couple of thousand. Three quarters of all plants in the northern hemisphere were killed.

What causes super volcanoes?
Super volcanoes differ from normal volcanoes in many ways. The stereotypical volcano is a towering cone, but super volcanoes form in depressions in the ground called calderas. When a normal volcano erupts lava gradually builds up in the mountain before releasing it. In super volcanoes when magma nears the surface it does not reach it, instead it begins to fill massive underground reservoirs. The magma melts the nearby rock to form more extremely thick magma. The magma is so viscous that volcanic gasses that normally trigger an eruption cannot pass, so a massive amount of pressure begins to build up. This continues for hundreds of thousands of years until an eruption occurs, which blasts away a huge amount of ground, forming a new caldera.

Where are there other super volcanoes?
Not all super volcanoes have been found, but one of the largest is in Yellowstone Park, USA. Scientists searching for the caldera in the park could not see it because it was so huge - only when satellite images were taken did the scale of the caldera become apparent - the whole park, 85km by 45km, is one massive reservoir of magma. The idyll landscape of Yellowstone (below) could soon explode with devastating consequences.

When will it next erupt?
Scientist have discovered that the ground in Yellowstone if 74cm higher than in was in 1923 - indicating a massive swelling underneath the park. The reservoir is filling with magma at an alarming rate. The volcano erupts with a near-clockwork cycle of every 600,000 years. The last eruption was more than 640,000 years ago - we are overdue for annihilation.

ect...