The city of Clearlake, Calif., is home to an active volcano that may erupt violently within the next 10,000 years, said Lisa Hammersley, professor of geology.

Hammersley was the speaker for the inaugural lecture for Sacramento State’s Center for Science, Technology, Engineering and Mathematics (STEM) Excellence at 7:30 p.m. Tuesday, Nov. 14 in the University Union’s Redwood Room.

Hammersley said the next eruption in Clearlake, a city about 80 miles west of Sacramento, would probably be a violent explosion of magma, not a small lava flow. Past eruptions in Clearlake “have been everything from small eruptions to large eruptions,” she said.

Hammersley has been one of the only geologists to conduct extensive volcanic research in Clearlake, a location that the United States Geology Survey recently named as a “high threat” location that should be monitored more closely.

Hammersley’s research indicated that the volcano in Clearlake, which she said last erupted around 10,000 years ago, may be “actively recharging” for a future eruption for several reasons.

The Earth’s crust around the volcano is giving off an usual amount of heat, and is emitting gases that are chemically similar to magma, Hammersley said.

“Gases don’t stick around very long . . . so there must be magma in the crust,” Hammersley said. She also explained that geologists have observed earthquakes below the Earth’s surface in Clearlake, and they “have a fluid signature,” which points to the existence of magma below the Earth’s surface. Geologists can tell the difference between earthquakes where something solid is breaking and where a liquid is moving, she said.

Hammersley explained some of the challenges she faced during her research, such as the difficulty in taking samples of the Earth’s crust in Clearlake.

“People there are quite private and don’t want you on their land,” Hammersley said. “Access to that land can be quite difficult.”

Although Hammersley’s lecture contained complex mathematical theories, some students found it easy to understand.

“It’s great that they make (these lectures) so approachable,” said junior Christine O’Neill, a geology major.

“(Hammersley’s lectures) are based in complex math that she explains really well to undergraduates,” said senior Tiffany Pratt, a geology major.

For a schedule of STEM’s future lectures or more information about the program, visit its website.

Cody Kitaura can be reached at [email protected]