Whats going on at yellowstone?, page 5

I think that some here are giving in to the fear monster a bit. Yes Yellowstone is a supervolcano and yes it is seismically active, and yes it could erupt but just a few minutes of reading can help us understand that there are many telltales leading up to an eruption.

General principles of volcano seismology

Seismic activity (earthquakes and tremors) always occurs as volcanoes awaken and prepare to erupt and are a very important link to eruptions. Some volcanoes normally have continuing low-level seismic activity, but an increase may signal a greater likelihood of an eruption. The types of earthquakes that occur and where they start and end are also key signs. Volcanic seismicity has three major forms: short-period earthquake, long-period earthquake, and harmonic tremor.

* Short-period earthquakes are like normal fault-generated earthquakes. They are caused by the fracturing of brittle rock as magma forces its way upward. These short-period earthquakes signify the growth of a magma body near the surface and are known as 'A' waves. These type of seismic events are often also referred to as Volcano-Tectonic (or VT) events or earthquakes.

* Long-period earthquakes are believed to indicate increased gas pressure in a volcano's plumbing system. They are similar to the clanging sometimes heard in a house's plumbing system, which is known as "water hammer". These oscillations are the equivalent of acoustic vibrations in a chamber, in the context of magma chambers within the volcanic dome and are known as 'B' waves. These are also known as resonance waves and long period resonance events.

* Harmonic tremors are often the result of magma pushing against the overlying rock below the surface. They can sometimes be strong enough to be felt as humming or buzzing by people and animals, hence the name.

Patterns of seismicity are complex and often difficult to interpret; however, increasing seismic activity is a good indicator of increasing eruption risk, especially if long-period events become dominant and episodes of harmonic tremor appear.

Using a similar method, researchers can detect volcanic eruptions by monitoring infra-sound—sub-audible sound below 20Hz. The IMS Global Infrasound Network, originally set up to verify compliance with nuclear test ban treaties, has 60 stations around the world that work to detect and locate erupting volcanoes.

So earthquakes are happening here but they are diagnosed closely by vulcanolgists as would a doctor closely monitor a patients symptoms in order to clarify exactly what is happening inside a patient.

If you take a look at the wiki on Prediction of volcanic activity you will get a better understanding of what happens and how seismologists and vulcanologists monitor the changes underground in order to predict volcanic eruptions.

The above paragraph I quoted is from this wiki Is there reason to worry? Of course, but not yet I think. Be prepared is the only advice I can see that would be a sound course of action.

There are many signs that can precede an eruption and I don't think that this swarm should be cause for concern, yet. Fascinating to see and understand our Planet is alive and deadly.

Krakatoa is another volcanic eruption to take a better look at, as well as Mt.StHelens. I took the wife and kids to see Helens 2 yrs ago and it is just freakin crazy the amount of energy released in one instant, they had a really nice museum on johnston ridge right across from the volcano and a great presentation that showed what led up to the eruption.

Most telling was not only the seismic swarms but the intense Ground Swelling that took place. Something like 5 to 6 feet in a relatively short period of time.

Be prepared. Make sure if you live near that beast you have a plan, but don't go running around saying the sky is falling yet. I would bet the USGS keeps a close tabs on it.