|MadSci Network: Earth Sciences|
Hello, Mike. Can scientists prevent volcanic eruptions? In a word, no. The forces involved are quite enormous. For example, the Mt. St. Helens blast was estimated at something like the power of a 5 megaton hydrogen bomb, and Mt. St. Helens is not especially large for a volcanic event. Stopping such a release of energy is akin to trying to contain the explosion of a hydrogen bomb, which is...um...pretty hopeless with present technology or any that this Mad Scientist can forsee. It may be possible in the distant future (the technology for this does not now exist) to lessen the worst violence of eruptions, but the methods may be almost as bad as the original result. One can think of using nuclear devices to perhaps "defuse" the biggest events by starting them before their full fury builds up. But this is hardly stopping it, just spreading it out somewhat. The energy is down there, and it will come out one way or another. That said, scientists can and do ameliorate the loss of life from an eruption by predictive methods. Sensitive measurements of earthquake swarms, gravitational anomalies (helps to tell the magma is moving), physical swelling of the volcano, and so forth, have done a lot to be able to predict roughly when an eruption is coming. Thus they can with reasonable confidence predict that there is a high likelihood of an eruption coming within a few days. This can give enough time to carry out evacuations of potentially affected areas and save quite a number of lives and some personal property. As to the formation of volcanos, this is a subject of such size that I can not even begin to really address it here in a short note. You must read a book or two, as there are many kinds of volcanoes and igneous formations in general. This covers everything from steaming fumaroles to mantle hot spots to subduction zones to mid-ocean ridges to...the list is nearly endless. There are a number of books solely on volcanoes. Here are two that I happen to own: "Volcanoes", by Gordon A. MacDonald "Volcanoes", by Cliff Ollier (I note in passing that earth scientists might perhaps use a little more creativity in their quest for book titles :-) Both will serve as a reasonable introduction to volcanoes. As will many other books on the subject. There is a quite interesting and very informative episode of the television program "Nova" on volcanoes, and it had a good deal about the methods of prediction of eruptions. There is a lot in it about the Mt. Pinatubo eruption in the Phillipines that I found especially fascinating (not the least being some of the footage of the eruption itself). The Web has zillions of sites on volcanoes, so many that you could probably spend your whole life trying to read them all. Try starting at the web site of the US Geological Survey (http://www.usgs.gov); they alone have 987 references to volcanoes (using the search engine on their home page).
Try the links in the MadSci Library for more information on Earth Sciences.