EOS 1048: Volcanology

March 31, 2004
relief sculpture on campus

In a field where change typically occurs at a glacial pace (erosion, sedimentation, continental drift), geology professor Alan Boudreau's EOS (Earth and Ocean Sciences) 104S, "Volcanology," is almost too much excitement for one class--eruption after awesome eruption, a highlight reel of nature's most explosive moments, past and present, all in the name of science.

The course, "suitable for both geology majors and those interested in environmental and land-use planning problems," looks at the geology of volcanoes and the benefits and hazards they present to society. According to Boudreau, volcanoes are mostly harmful to their surroundings. There's the 2,000-degree (Fahrenheit) lava, the atmospheric effects of ash clouds, the landslides, and the air pollution. "Mount Kilauea [in Hawaii] emits more sulfur dioxide, a serious greenhouse gas, than any anthropogenic source in the United States," he says.

On the other hand, even the most devastating of eruptions can do the world good. "Volcanic rocks tend to form fertile soil," he says. "And," he says, exploding with enthusiasm, "the pumaceous rocks are the source of griddle bricks used to clean the grills in fast-food restaurants!"

Class is divided into two major research projects. For the first half of the semester, students review in detail a historical eruption of their choosing, say, Mount Vesuvius, which, in 79 A.D., buried the towns of Herculaneum and Pompeii, and, incidentally, gave rise to the geologic term "lava," coined by Neapolitans who took the Italian word meaning "a stream caused suddenly by rain" and used it to describe the molten rock streaming down the mountain. For the second half, students assess a current site of known volcanic risk (Mount Pinatubo in the Philippines, Mount Santiaguito in Guatemala) and what is being done to understand and alleviate the hazards.

"One cannot control an eruption," says Boudreau. "Where they tend to be explosive, like Mount Saint Helens, the main mitigation technique is land-use planning: Do not allow large communities to settle in known hazard areas. In Japan they have a number of diverter dams to channel lava and small pyroclastic flows [from Mount Unzen] away from populated areas."

Lectures and discussions cover the physical nature of various kinds of magmas, eruptive mechanisms, volcanic geomorphologic features, gases, hydrothermal phenomena, and effects on atmosphere and climate.


Introductory Geology (EOS 41)


Volcanology by McBirney and Williams


There are two midterms

Research reports and presentation on two topics: one historical eruption and one site of known volcanic risk


Alan Boudreau's expertise lies in origins of igneous layering, specifically the numerical modeling of "post-cumulus" processes such as crystal aging and compaction. He also teaches EOS 108: "Geology of the Hawaiian Islands," a class on the geology and natural history of the Hawaiian Island chain, featuring a ten-day field trip to Maui and the Big Island over spring break. "It is always amazing to me that one can be walking on what appears to be solid rock but is actually still molten six inches beneath the surface," he says. "It's the excitement of experiencing active geology. And it's hot. One has to be careful not to melt the soles of one's shoes."