(Photo by Shelly Hanks, WSU Photo Services).
Several volcano eruptions were witnessed on campus recently. Water volcanoes that is…Geology students watched simulations of how a volcano’s pressure builds up and releases energy, sending a trail of water about 30 feet high in the air.
According to Kurt Wilkie, an instructor in the Geology department, Geology 101 uses the water volcano to demonstrate why composite volcanoes like Mount St. Helen’s or Mount Rainier have pyroclastic style eruptions.
Magmas generated at convergent plate boundaries contain dissolved gasses and as the magmas rise the gasses are released from the molten rock. The magma and overlying volcano are unable to slowly release the gas, much like a shaken bottle of soda pop. This causes the pressure to continue to build until the strength of the rock is overcome and the volcano erupts, Wilkie said.
In the water volcano demonstration, a plastic soda bottle is over pressurized until it ruptures, releasing the gas and forming the water volcano, Wilkie said.
