Volcanoes!

Links to the work:
http://sciencematters.berkeley.edu/archives/volume1/issue2/story2.php
http://www.berkeley.edu/news/media/releases/2003/11/26_bubbles.shtml
http://www.nature.com/nature/journal/v426/n6965/full/nature02138.html

Researchers affiliated with the University of California Berkeley have created experiments that further human knowledge of volcanoes, and provide insight on how and why volcanoes explode. A consistent contributor to this project is UC Berkeley professor of Earth and Planetary Science, Michael Manga. Manga has an impressive educational background. He received his B.S. in geophysics at McGill, his S.M. in engineering sciences from Harvard, and his Ph.D. in earth and planetary sciences from Harvard as well. He has been a professor at UC Berkeley since fall of 2001. His work on volcano theories began with a graduate student named Helge Gonnermann. Together, they came up with a theory about why volcanoes sometimes viciously erupt, while other times the eruption is a slow ooze. I found their hypothesis from ScienceMatters@Berkeley, and it was also published in the journal, Nature. The article is Volume 1, Issue 2 in ScienceMatters@Berkeley, which was published on February 13, 2006. There was also a press release a few years earlier about this topic on UC Berkeley news. The press release was published on November 26, 2003. Manga and Gonnermann’s written hypothesis was received by Nature on May 19, 2003, and was accepted November 15, 2003.

Before I talk about any theories, let’s recap the elementary explanation about volcanic explosions. Inside a volcano is liquid magma. The liquid magma rises from the magma chamber located several miles down. In the volcano, dissolved gasses form bubbles. These bubbles grow because of increasing pressure. The magma pressure decreases while it rises. The bubbles then grow, which makes the volume of the magma increase, so then it rises faster. The loss of dissolved gas (which are now bubbles) make it harder for the magma to flow, so the probability that it will break is much higher. The pressure accelerates until the magma finally fragments and explosion occurs. It’s like a shaken soda. When a large volume of gas in bubble form (like the carbon dioxide in soda) releases, it blasts from the top (like a soda would explode when opened).

Predecessors to Manga and Gonnermann’s believed that explosive eruptions of volcanoes were simply caused by fragmentation (breaks). Fragmentation releases the gas bubbles which are trapped in the liquid. In a volcano, magma fragments as it rises to the surface. The pressure of escaping gas breaks the magma and blows it out, just like champagne escapes when the cork is released (Manga). Manga and Gonnermann challenged this idea, saying that fragmentation is definitely a huge part in volcanic eruptions, but not the only cause. In fact, their new theory said that fragmentation occurs in almost all volcanic eruptions. They believe that magma is always fragmenting while it surfaces, but when gas is steadily escaping the pressure is not enough to cause an explosion.

Manga and Gonnermann have explanations for both explosive (violent), and effusive (oozing) eruptions. For explosive eruptions, magma rises fast. Since the magma is rising at a rapid rate, the gas pressure increases, and bubbles grow at a higher rate. The magma cannot keep up with the growing rate of bubbles, so it can’t continuously release pressure. This pressure causes the magma to fragment quickly and there is an explosive release of the gas pressure.

Effusive eruptions, according to Manga and Gonnermann, constantly fragment while the magma rises to the surface. The constant fragmenting breaks the gas bubbles and releases a lot of gas before the magma even reaches the surface. Once the magma reaches the surface, there is little pressure, or bubbles left; therefore, there is no explosion.

To put the two different kinds of eruptions into perspective Manga gave a good, real-life example that makes the theory clear. "Silly Putty is the same way - it deforms smoothly if you pull slowly, but it breaks if you pull quickly." When magma is evenly stretched, at a slower rate, releasing gas along the way, an explosion won’t occur. However, if the gas bubbles are increasingly putting pressure on the magma, it cannot keep up and will suddenly break, causing an explosion.

Manga and Gonnermann came up with their theory that fragmentation is universal because of their studies on California’s Big Glass Mountain Volcano. There were multi-colored bands on the rocks that they studied. “The bands, which contain different concentrations of microcrystals of the mineral pyroxene, are created by shear forces as the magma rises under the volcano and as it flows on the surface” (ScienceMatters@Berkeley).

From their joint hypothesis, Manga started doing funded research by the National Science Foundation and the Sloan Foundation with post-doctoral researcher, Atsuko Namiki. This pair of researchers do experiments with an “in lab volcano simulator” (ScienceMatters@Berkeley). Their work it to try to test their theories about magma fragmentation, and specifically the fascination on how and why magma fragments. Using a corn-syrup type liquid they use their machine to test fragmentation with pressure change. In their volcano simulator they have a camera which “captures 2,000 frames per second, enabling the researchers to analyze the liquid fragmentation” (ScienceMatters@Berkeley). Manga explaines, "these kinds of experiments help us predict whether something like a big landslide at Mount Saint Helens, for example, would change the pressure enough to cause an explosive eruption."

Elementary schools have to find fascinating topics to keep children engaged in learning. Things like mummies, sharks, and volcanoes typically spark children’s interests, as well as mine. Ten years later, I still find myself reading the news about new discoveries on these topics. When I was looking for a “present meaningful scientific contribution to human knowledge” I decided to take a look at the source Professor Wade provided. I looked through a few issues of science related topics to find one that I could not only partially understand, but one that also sparked my interest. I came across an article called, “An Explosive Theory About Volcanoes” by David Pescovitz. I don’t know if I have spent too many hours thinking about journalism class, but the headline caught my attention because of the play on words. Also, I figured it was time that I update myself on this type of science I had once found fascinating in the fifth grade.

The impact this will have on the world is that these theories and experiments may lead to one day being able to predict when a volcano will erupt, and whether it will explode or effuse. Also, this research will help determine other natural contributions to the eruption of volcanoes, like previously stated, landslides.
I definitely think that this is science, because volcanoes are a part of nature, because they are not manmade, and nature is science. Science, as defined by Merriam Webster is “knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method.” Based on that definition, this study of volcanoes is science. The researchers are gaining knowledge about volcanoes, and are proving truths about them. Also, they are studying the general laws of how volcanoes work, while discovering new ones. The laws Manga and Namiki are trying to define are tested through scientific method, their volcano simulator.

This connects with what we have been learning in class, especially with Fancis Bacon’s optimism towards knowledge and his book Instauratio Magna. There is a quote from the bible from the Book of David that states, “ Many shall pass to and fo, and science shall be increased (Shapin 20). This applies to the new knowledge about volcanoes because there is a continuous need to know more about them. There have been many scientists before Manga, Gonnermann, and Namiki, but their knowledge has helped the three understand what they do now. There will also be people after them who will continue to find new discoveries.

Dictionary and Thesaurus - Merriam-Webster Online. Web. 16 Oct. 2009. .

Manga, Michael, and Helge Gonnermann. "Explosive volcanism may not be an inevitable consequence of magma fragmentation." Nature (2003). Nature: International Weekly Journal Of Science. 15 Nov. 2003. Web. 12 Oct. 2009. .

Pescovitz, David. "An Explosive Theory About Volcanoes." ScienceMatters@Berkeley. University of California, Berkeley, 13 Feb. 2006. Web. 12 Oct. 2009. .

Sanders, Robert. "What makes volcanoes explode? It's the bubbles." UC Berkeley News. University of California, Berkeley, 26 Nov. 2003. Web. 12 Oct. 2009. .

Shapin, Steven. The Scientific Revoltuion. Chicago: University of Chicago, 1998. Print.

"Volcano Facts, Volcano Information, Volcano Videos, Volcano Photos - National Geographic." Environment Facts, Environment Science, Global Warming, Natural Disasters, Ecosystems, Green Living - National Geographic. Web. 17 Oct. 2009. .