scientists could understand what was going on inside Baker, its sister to the south — Mount St. Helens — roared to life, stealing the show and their attention.

Now geologists at Western Washington University are leading the effort to find out what's been percolating beneath the volcano's surface since its headline-grabbing antics in 1975.

"People are beginning to recognize there's a lack of understanding of Baker," said Juliet Crider, WWU associate professor of geology who has led a study into what happened when Baker heated up.

"Among the Cascade volcanoes, I would say it's one of the more active," she said. 'That doesn't mean an eruption is imminent. But it means it's interesting. Something is happening there."

What could be happening is the focus of The Geological Society of America meeting next month in Bellingham. Baker is one of 27 major volcanoes in the Cascade Range, which stretches from British Columbia down to Northern California.

The mountain has long been overshadowed by the 14,410-foot-high Mount Rainier, which towers over the Seattle-Tacoma area and its more than 3.2 million residents, and Mount St. Helens, which erupted on May 18, 1980 — hurling volcanic ash high into the air, decimating forests for miles around, and leaving 57 people dead.

These days, Baker trembles just once or twice a month with small earthquakes, an indicator of seismic activity. By comparison, seismometers record up to 10 times that number each month at Rainier and thousands of small earthquakes at St. Helens.

That has made the snowy hump of the 10,778-foot-high Mount Baker seem like a silent sentinel over the Whatcom County skyline.

But it hasn't always been a benign presence.

EARLIER RUMBLINGS

Volcanic activity in the Mount Baker area dates back more than 1 million years, with the largest eruption of today's Baker occurring 6,600 years ago. That sent what the U.S. Geological Survey describes as a "blanket of ash" more than 20 miles to the northeast.

In 1843, the volcano exploded and formed Sherman Crater. Explorers at the time described rock fragments coming down "like a snowfall" and the forest on "fire for miles around."

In 1975, plumes of steam from the same crater raised fears that increasing heat would melt nearby glaciers and cause lahars — flows of mud, debris and water capable of rushing down valleys and stream channels at 20 to 40 miles per hour. Lahars have enough power to move houses, trees and boulders close to the source of the flow, according to the USGS Cascades Volcano Observatory.

Worried that lahars would flow into Baker Lake or Lake Shannon, damaging the Upper Baker Dam and causing flooding, officials evacuated area residents and businesses, and closed campgrounds around Baker Lake in June 1975.

Then Baker calmed, Mount St. Helens exploded and no one returned to conduct an in-depth study of what had happened beneath the volcano's surface in 1975. Was there new magma? Was Baker's surface expanding? Could there be a repeat of 1975?

Then last summer, a group of researchers and graduate students made their way up to Baker to help answer those questions for a study led by Crider.

Using $107,039 from the National Science Foundation for a two-year project, members of WWU’s Geology Department set out to measure the gravity on Sherman Crater, the distance between survey points using high-tech global positioning systems, and to take gas samples from the fumaroles, or steam vents, in the crater. The team received help from researchers at USGS and Simon Fraser University in Burnaby, B.C.

EXAMINING BAKER

While studies on other volcanoes have delved into gas, GPS or gravity, Crider said none had looked at all three at the same time. As for Baker, it would be the most extensive study of the volcano since at least 1977. It marked the first time the USGS conducted ground-based monitoring since 1983.

They found increased acceleration of gravity, smaller distances between some survey points, and high emissions of carbon dioxide and sulfur dioxide.

Taken separately, each finding would have given ambiguous answers to the presence of magma.

Together, they suggest that new magma might have formed in the volcano in 1975, or earlier, but never erupted. Since then that magma, or molten rock, has been cooling, releasing gasses and contracting. Baker, essentially, seems to be taking a geologic nap.

And that is good news for the region's inhabitants — for now.

"We should recognize that Baker is an active volcano and be cognizant of the hazards associated (with that), but not be afraid that it's going to erupt," Crider said.

She will present the study’s findings during the regional meeting of The Geological Society of America at WWU next month.

Organized by Dave Tucker, a WWU research associate in geology who has published papers on the volcanic history of Baker, the May 4-6 event will include a daylong symposium on Mount Baker research.

"Western is the focus of research at Mount Baker. And it makes sense because it's in our backyard," said Tucker, whose field of study includes the volcano's 1843 eruption.

That eruption was the second-largest Baker eruption known in the geologic record and deposited ash 25 miles away, he said.

"That means people have to sit up and take notice of Mount Baker," Tucker said. "It ain't dead."

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