Posted: Feb 28, 2010 9:17 PM
Updated: Feb 28, 2010 9:17 PM
GREAT FALLS - The disaster in Haiti and the magnitude 8.8 earthquake in Chile over the weekend, along with the tsunami warnings for Hawaii and Japan, are raising awareness about these natural disasters. We took a closer look at the science and if Montana could be affected.
Millions of lives have been lost in the Haitian earthquake and the death toll is rising in central Chile and a logical question would be, why are there so many earthquakes?
Walter Mooney of the U.S. Geological Survey said, "The answer is really quite simple. We do have 14, on average, 14 magnitude 7.0 earthquakes per year, most of them are harmless - they occur out in the ocean basin."
Although the recent earthquakes have not been so harmless, Mooney says there is nothing unusual going on here.
"In Chile we have 8.0 earthquake or larger about every decade. So this magnitude 8.8, although it's really quite a remarkably large earthquake, the third-largest in the last hundred years, Chile is the place that has those kinds of earthquakes" he explained. "In short, we aren't seeing any unusual patterns, we're just seeing a lot of earthquakes ocurring nearby to where people live, and so we're noticing them more."
Mooney says earthquakes spread energy to the rest of the earth, especially when they are of a large magnitude like the one in Chile. So how will all that energy affect the Treasure State?
"What we expect in Montana, and in Yellowstone and neighboring areas, is that there will be an increase in the number of micro-earthquakes" Mooney explained. "These are the earthquakes that people don't normally think about or even notice (with) magnitudes as low as one or two or three. Very much like the kind of fizzing you'd get if you shook a can of soda."
The recent swarm of small earthquake near Yellowstone National Park served as a reminder that Montana is one of the most seismically-active states; fortunately, the vast majority of earthquakes are minor, primarily of interest only to geologists and researches.
But occasionally, Montana earthquakes can be larger - and deadly. According to the Federal Emergency Management Agency, in 1935 there were a series of earthquakes between Yellowstone and Helena that killed four people and caused more than $4 million dollars worth of damage.
The 1959 Hebgen Lake earthquake in Montana killed 28 people, and caused more than $11 million dollars worth of damage.
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