Thursday, February 5, 2009

SWARM!!



Swarm

When you hear this word what is your first thought?? Mine is of a swarm of angry bees looking for unprotected flesh! But the last week of 2008 I heard this word used in an entirely different, and possibly more dangerous context.


Between December 26th and 29th more than 250 small earthquakes occurred in Yellowstone National Park . When that many tremors happen in a small span of time they are referred to as a swarm. Even though an earthquake swarm is problematic, it is what it could signal that is dangerous.

Yellowstone National Park is actually the caldera of a super volcano. For clarification, a caldera is defined as “a volcanic crater that has the diameter many times that of the vent and is formed by the collapse of the central part of a volcano or by explosions of extraordinary violence”. The entire park is the depression of a caldera more than twice the size of the island of Oahu that is the result of an eruption about 600,000 plus years ago.

To make a comparison with an event that most of us remember, Mt. Saint Helens ejected 1.4 billion cubic yards of ash that was detectable over an area of 22,000 square miles. The last Yellowstone eruption ejected 2,500 TIMES the ash of the Mt. Saint Helens eruption.

So what does this actually mean?? Yellowstone is continuously monitored by geologist. Since 1923, when scientist started measuring the elevation of the caldera it has risen 35 inches. Since mid-2004 the rate of upward movement has risen up to 3 inches a year, more than three times faster than previously measured. Does that mean an eruption is eminent? Who knows??

No one can predict when, but there are 8 known super volcanoes worldwide and a future eruption is inevitable with 100% probability. So how does one prepare for such a catastrophic event???

We cannot….it is impossible.

1 comments:

Anonymous said...

Make sure you have some cold Milwaukee on hand!!!