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Researchers Find Some Volcanoes 'Scream' At Increasing Pitches Until They Blow
vinces99 writes "Swarms of small earthquakes often precede a volcanic eruption. They can reach such rapid succession that they create a "harmonic tremor" that resembles sound made by some musical instruments. A new analysis of an eruption sequence at Alaska's Redoubt Volcano in March 2009 shows the harmonic tremor glided to substantially higher frequencies and then stopped abruptly just before six of the eruptions. Scientists at the U.S. Geological Survey's Alaska Volcano Observatory have dubbed the highest-frequency harmonic tremor at Redoubt Volcano 'the screams' because the episodes reach such high pitch compared with a 1-to-5 hertz starting point. Alicia Hotovec-Ellis, a University of Washington doctoral student in Earth and space sciences and an author of two papers examining the phenomenon, has created a 10-second recording and a one-minute recording that provides a 60-times faster representation of harmonic tremor and small earthquakes."
It's the thetans getting ready to take a massive shit in Tom Cruise's mouth and fill him with even more blessings.
So, it's like a teapot when it gets boiling?
There's gotta be!
...like my wife.
Gigidity
(the password is: squirt)
At their peak, just before they blow, these "screams" get to a high enough frequency that humans could hear them. Of course, to us it would sound like a low frequency rumble.
In other words, if you are standing on a volcano, and start to hear it grumble, get away. Fast.
Sounds like many a marriage, except after the wedding all blowing stops.
I bet the volcano's still have better pitch control than Justin Beiber.
sudo make me a sandwich
some volcanoes will erect before they blow.
after a night at Taco Bell
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Could this be a possible explanation to how animals sometimes perceive an impending disaster? What decibel would this be at from, say, five miles?
Check out the time compressed sound recordings- pretty awesome.
love is just extroverted narcissism
This obviously does not apply to volcanoes in space.
Because in space, no one can hear you scream.
More than coincidence?
Please do not read this sig. Thank you.
Have gnu, will travel.
There's a big bad boomin' system, blowing speakers, woofers and tweeters.
it's the giant lemongrabs
It's only a model.
If you RTFA you would see this:
She documented the rising tremor frequency, starting at about 1 hertz (or cycle per second) and gliding upward to about 30 hertz. In humans, the audible frequency range starts at about 20 hertz, but a person lying on the ground directly above the magma conduit might be able to hear the harmonic tremor when it reaches its highest point (it is not an activity she would advise, since the tremor is closely followed by an explosion).
However this is slashdot so no need to RTFA, just carry on with redundant questions veiled in the shape of a seemingly innocuous post.
Volcano IS a woman!
I swear to God...I swear to God! That is NOT how you treat your human!
my policy is to not follow links. if some information was important enough, it would be put in the summary / post. if it's not important, then you just refer people to the link. so i just stick to what's important and not waste time on the links.
You want to upvote/downvote? Go back to Reddit! Here we mod up/mod down.
But how else am I supposed to use the force to lava-surf?
Monstar L
Volcanoes always fascinated me, especially in my school days. I remember reading in history about how a whole city was carpeted by volcanic ashes and suffocated everything. Now to read about the ‘screaming’ volcanoes it seems more of a mythic happening. I’m certain people of old had some interesting stories to attach to this attribute of volcanoes. Sandra V. Bolee.com