googleplus linkedin pinterest snapchat vimeo youtube
utulsa.edu

Geosciences alumna studying jet acoustics of volcanoes

As a young girl at a Girl Scout camp out, Kathleen McKee (BS ’08) discovered the wonders of nature. Today, she studies jet acoustics in volcanoes and has developed a fascination with geology. When the TU Department of Geosciences recruited her to Tulsa, she seized an opportunity to arrive early the summer before her freshman year to participate in a six-week internship. Under the advisement of Associate Professor Bryan Tapp, she studied brine scars at the Tallgrass Prairie Preserve.

“TU had great advisers who taught us you can do anything you put your mind to,” she said. “I received support and inspira- tion from Dr. Tapp.”

Kathleen McKee

Kathleen McKee spent a summer at the rim of Japan’s Aso Volcano installing microphones to record jet noise.

After graduating in 2008, McKee earned a master’s degree in geology from Michigan Technological University while serving in the Peace Corps. Living abroad in Peru allowed McKee to learn about other elements of her field and participate in commu-

nity development projects. She worked as a trained water and sanitation volunteer, teaching hand washing and water treatment methods, building latrines and organizing a library in cooperation with local schools and community leadership. McKee returned

to Michigan Tech after the Peace Corps to finish research for her degree. She said volunteering abroad was invaluable: “It was very fulfilling, living in another country and culture and learning the language.”

McKee found a way to incorporate science with her passion for humanitarian service during a volcano seismology class in grad school. By producing rivers of lava and suffocating showers of ash, volcanoes directly affect human life. McKee decided
to specialize in volcano geophysics as a doctoral student at the University of Alaska Fairbanks. She and her adviser study and use infrasound, low frequency sound below human hearing, to better detect, locate and characterize volcanic activity. When volcanoes erupt, they generate sound as gas and ash are ejected into the atmosphere. If this thrusting of gas and ash is sustained, it produces a vibration similar to the sound of jet flow from a rocket or airplane engine but inaudible to the human ear. McKee hopes to solve many of the mysteries of volcanic activity through application of jet acoustics.

“The massive flow coming out of a volcano disturbs the atmosphere in a very similar way,” she said. “The shape of sound waves from rockets and jet engines is the same. We’re just shifting to lower frequencies.”

McKee spent the summer of 2015 collaborating with local scientists to record sound waves at Aso Volcano in southern Japan. She positioned six microphones at the crater rim to record the sound produced by a small vent at the bottom of the crater. Known as a fumarole, the vent releases hot gas in a volcanic envi- ronment and can sound like an airplane.

“If we can determine how much gas is coming out and how fast, we can better predict the hazards,” McKee said.

Equations have been empirically derived to determine jet flow parameters, such as velocity, from the recorded sound, but she said those methods don’t hold true for volcanoes. The study of volcanic jet noise has additional complexities and challenges such as the presence of solids within the jet flow, complex vent geom- etry and limited recording opportunities and locations. McKee is analyzing last summer’s data in hopes the sounds from the small vent will prove to be jet noise. Gas-jetting fumaroles could serve as natural laboratories in future studies to develop new equations for volcanic jet flow.

A geology journey that began in Tulsa has taken McKee around the world, and she expects to complete her doctoral thesis next summer. Following her degree, she hopes to continue research at a volcano observatory in the United States — maybe even in Alaska.

“There’s amazing geology here right in your face,” she said. “It isn’t easy, but the wilderness is an adventure in itself.”