A Feeling for Land

March 01, 1983

"The mountain was spouting ash then, and steam. At dusk, it sent up these marvelous orange columns. I pitched my tent on the ridge above Maratta Creek and stayed there a couple of days. I read reports, and watched the mountain, and let the geology run around inside my head."

B&W photo of a volcano erupting

Barry Voight was at Mount St. Helens in April 1980. The U.S. Geological Survey had asked Voight and other geologists to help monitor the mountain, whose discharges and earthquakes warned of imminent eruption. They survey wanted to predict when the volcano might erupt and where the eruption would go. Voight says, "They asked my opinion on whether the potential existed for a massive avalanche on the mountain's north flank. The answer they got was ‘Yes.'"

After 10 days at St. Helens, Voight returned to Penn State. A month later—May 18—the mountain exploded. The eruption was the first volcanic event in the contiguous 48 states in 63 years. It removed 1,300 feet of the mountain's summit, snapped 150-foot Douglas firs 17 miles away, and leveled 200 square miles of forest. Its ash, ice, magma, and mudflows killed over 2 million birds, fish, and mammals, including 61 people.

When Voight heard the news, he arranged for fellow faculty members to take his classes. He reached the mountain three days later.

"We came in by helicopter, flying up the Toutle River," he says. "The whole goddam valley was gone—filled in. Everything was gray. There was no visual reference that I could tie into."

Barry Voight's office is a small, square room with a window to the south. It contains nine filing cabinets, three map files, four bookcases, and a half-dozen shelves (all full), a pronghorn antelope skull, a cowrie shell, rock corings, a desk, typewriter, and, on the floor, cardboard boxes of rocks and papers. A creamy piece of pumice—the size of a fist, the weight of a pack of cigarettes—sits on the desk. A gray, dark-fissured, watermelon-shaped rock occupies a cabinet top. "That's a volcanic bomb," Voight says. "In between a rhyolite and an andesite—about 64 percent silica."

Voight has graying blond hair, a beard a shade darker. He is wearing a black sweater and tan corduroy pants with worn knees. His eyes, pale blue and open wide, fix on objects around the room.

"I was one of about 20 geologists at St. Helens," he says. "There were people in mud flows, ash stratigraphy, gas chemistry. Plenty of volcanologists, mostly from Hawaii, but volcanoes there are entirely different. Hawaii is a plate drifting over a hotspot. The Cascades are plates converging—one riding up over the other.

"You gotta remember, they didn't get much money to study the mountain until after it blew. Helicopters cost $300, $400 an hour. They didn't have all the instrumentation they've got now. But they had data to work with. Two survey geologists, Rocky Crandell and Don Mullineaux , had recognized Mount St. Helens as dangerous goddam volcano. In a 1978 report, they called it the most likely volcano in the Cascades to erupt—it's been the most active over the last 2,000 years.

"They'd mapped the surface deposits and made inferences about the internal geology. I studied their map, and a map of the cone by Cliff Hopson. I looked for zones of weakness and strength. I looked at fracture patterns, from the air and from photos. On the north portion of the summit, I examined fractures and helped set out geodetic targets. Later, measurements of other targets on the north slope showed that the mountain was swelling about five feet a day in a northward, lowering direction.

"Phreatic eruptions—steam eruptions—had blown a 750-foot crater out of the summit. The steam told me there was a high water table. Water and landslides go together. A slope is held together by friction. Fluid pressure in the pore spaces of rock directly influences frictional resistance. The more water and the higher the water pressure, the less resistance—and the more likely a mountain will slide.

"I knew a big slide at St. Helens could reach Spirit Lake, four miles north, where crowds of tourists sometimes gathered. A slide could also send a flood down both forks of the Toutle. It could expose pockets of pressurized steam and magma."

Before leaving, Voight gave the Geological Survey his initial conclusions in the form of a pencil drawing. The drawing was posted on a bulletin board in the survey's Mount St. Helens office in nearby Vancouver, Washington. Voight depicted St. Helens in profile. A dotted line showed the part of the mountain that he felt might slide. Above St. Helens, Voight added two cautionary sketches: the 1925 Gros Ventre slide in Wyoming and the 1959 Madison Canyon, Montana, avalanche.

His notes on the drawing: "Slide mass front can reach Spirit Lake. Debris and mudflows generated at front can go much farther. Magma pocket—boils when surface load removed suddenly—possible trigger for pyroclastic event."

Harry Glicken met Barry Voight three days after the eruption. Glicken remains at Mount St. Helens, mapping the avalanche. "Out here," he said, "Barry has a reputation for having said the right thing at the right time. He predicted the avalanche. He actually got something down on paper. Other people didn't."

Bob Decker is scientist-in-charge at the U.S. Geological Survey's Hawaiian Volcano Observatory. "Barry's was an extremely perceptive analysis of what might happen," said Decker. "In hindsight, he was the one who foresaw the event most clearly."

According to Penn State geologist Gene Williams, Voight is probably the most creative person in the department. "He's a very good theoretician," Williams said, "and he can apply theory to problems in the field. Barry has tremendous powers of concentration. He attacks everything he does with great intensity. Sometimes you get the idea he's unsympathetic to you as a person—but it's really only that he's focusing on something else at the time. He's a good geologist. He has feeling for land."

Avalanches are Barry Voight's speciality. He has been studying them for 23 years, since he was a senior double-majoring in geology and civil engineering at Notre Dame. There, he analyzed slides along Lake Michigan. Later he moved on to larger avalanches: rockslides and glacier falls measured in cubic kilometers. He has autopsied prehistoric avalanches, dug into avalanchesin Italy and New England, written about avalanches in Alaska and Norway. In the late 1970s, he edited a two-volume book, Rockslides and Avalanches, which its publisher called "the standard reference work on mass movements." The avalanche that peeled away Mount St. Helens' north face, he says, is the largest in recorded history.

He unfolds a map and spreads it on his desk. Its title is "Geologic Map of Proximal Deposits and Features of 1980 Eruptions of Mount St. Helens, Washington." On paper, St. Helens is a pink and brown oval. To the north, away from the mountain, flow patches of tan, blue, salmon, and green. Winding west is a broad purple ribbon.

Voight points at the ribbon. "That's the avalanche. About 3 billion cubic meters. Sixteen miles long, a mile wide, with an average depth of 45 meters.

"It's complicated as hell, especially close-in. The blast followed the avalanche and swept over it, covering up some of the avalanche deposits with ash and pyroclastic flows. The avalanche, moving slower, spread over the blast deposit in places. Some of the ash has been washed away by rain and flooding—each summer we see more lithologic types exposed.

"I'm working on the avalanche with Harry Glicken and Dick Janda, from the survey. We're trying to understand how it went as far as it did, trying to reconstruct the innards of the volcano from what's lying on the ground. A lot of our data went into this map."

In northern Japan there is a mountain called Bandai-San. In 1888, Bandai-San exploded, blasting a horseshoe-shaped crater out of the side of its summit, burying seven villages, killing 461 persons. Today, pines and willows cover its slopes, and a ski trail winds into the crater.

Voight read about Bandai-San in the 1889 Journal of the College of Science, Tokyo Imperial University. In the lithographs, Voight saw the cone of Mount St. Helens: shape, slope, and potential sliding surface. A massive slide on the north slope of Bandai-San had released the eruption, a huge lateral blast far more devastating than a classic vertical eruption of similar size. In his May 1, 1980, report to the Geological Survey, sent back to Vancouver after he had returned to Penn State, Voight wrote: "A catastrophic event of the kind observed at Bandai-San—in which an explosively motivated fragmental flow devastated an area of more than 70 km2 (27 mi2)—must be regarded as a legitimate possibility."

Gary Rosenquist was one of the curious who had converged on St. Helens. A Seattle-based photographer, he set up camp in Bear Meadows, 11 miles northeast of the mountain. On the morning of May 18, Rosenquist saw steam rising from the summit. He mounted his camera on a tripod, and took a photograph. Moments later, a companion shouted, "The mountain is going!" The volcano's fire-hot blast, traveling at aircraft speed, swirled around the high ground where they were standing, and passed on. Unlike many other observers, Rosenquist and his friends survived.

Rosenquist sold his photos to National Geographic Magazine, and lent a set to Barry Voight.

Of 23 frames, two show the volcano releasing a small billow of white steam, and 21 show the avalanche and eruption in various stages of development. The frames are sequential, taken at irregular intervals. To figure out the speeds of the avalanche and other components of the eruption, such as the explosion plume and the blast cloud, Voight needed to computer exactly when each slide was taken.

He had the photographs blown up. He concentrated on three ice avalanches that had slid off Forsyth Glacier, about halfway down the mountain. Knowing the topography, the behavior of an avalanche, and the effect of friction, he was able to calculate how long it took the ice to churn down the mountain. By tracing the ice fall's progress, he could compute the amount of time between consecutive frames.

First, he had to fix a starting time for the avalanche.

"It was an earthquake that set off the slide," he says. "According to seismic recorders, the quake occurred at 8:32:11.4 a.m., Pacific Daylight Time. For an upper boundary, I chose the moment when the blast front wiped out seismic station SOS, between St. Helens and Spirit Lake. That happened at 8:33:29.5."

The earthquake, Voight reasoned, probably started minor rock and ice falls in the crater denting St. Helens' summit. A few seconds after the earthquake, a major fracture cracked its way along a bulge of magma that had been swelling the mountain's north side. The rocks "rippled and churned" for several seconds, according to two people who had been flying over in a light airplane. Then the north face started down—8:32:21, Voight estimates.

Some 26 seconds later, Rosenquist's photos begin to record the event. On the mountain's northeast shoulder, ice blocks skid down the slope like water foaming over rocks. The summit collapses in a second slide that follows the first down the mountain. Gray ash blossoms from the summit and from the scarp left by the first slide.

"As the slides moved out," says Voight, "they decapitated magma columns near the summit. That turned the volcano loose. Pressurized steam and magma blew out in the horizontal blast. It lasted about 15 minutes. Then, for the next nine hours, it went vertical."

"Barry is singleminded to the point that he drives himself and others around him to exhaustion," Rudy Slingerland said. Slingerland is in Voight's department at Penn State. "When he taught field camp for our undergraduate students out West—the students map faults and terraces and learn the basic field techniques—Barry took this group deep into the high country, backpacking away from roads and trails. I guess he drove them into the ground. The trip happened five or six years ago, but it survives in the folklore of our undergraduates. It's referred to as the Bataan Death March."

"He becomes totally immersed," said Dick Janda. Janda is a geologist at the David A. Johnston Cascades Volcano Observatory, a Geological Survey outpost set up in 1982 to study volcanism in the Cascades Range. Janda, Glicken, and Voight wrote "Catastrophic Rockslide-Avalanche of May 18." The article appeared in Geological Survey Professional Paper 1250, "The 1980 Eruptions of Mount St. Helens, Washington," an 8-pound volume published by the U.S. Department of the Interior. "I've known Barry since 1959," Janda said, "when we were students together at field camp in Wyoming. He stays at my house when he comes to St. Helens, and when he's here, it's long hours—up at five and to bed at one or two.

"Barry sometimes gets so involved in geology that he isolates himself from others. He's not selfish or self-centered, as some people believe; once the task is finished, he's back to being a warm, generous man with a good sense of humor."

"He comes off as being kind of scattered," Tom Casadevall said. "He's not. In his mind, I think he knows exactly what he's looking for." Casadevall earned a doctorate at Penn State in 1976, and now works with Janda at the Cascades Volcano Observatory. "The first time Barry came to Washington," said Casadevall, "he didn't have a credit card, so he couldn't rent a car from Hertz or Avis or another of the big companies. He needed a car to do field work. He went to a local outfit and came back with a beat-up two-tone Pontiac. We called it his pimpmobile, but it turned out to work pretty well, because he could sleep in it.

"Barry once made a comment that stuck with me. He said that most of the people who are geologists today are the kind of people who were outlaws a hundred years ago."

Voight cycles slides through the projector. It is the day following our interview. He is wearing the same black sweater and tan corduroys he wore the day before. We sit on a lab table in a darkened classroom.

St. Helens. The mountain, pre-eruption, is conical and streaked with snow. A column of gray smoke, tinged pink by the setting sun, rises from the summit. Other columns march east, unraveling in the wind.
"I took this picture from my camp above Maratta Creek," Voight says.

A bathroom with wires snaking across the floor. Voight explains that the concrete pad provided a stable base for measuring ground tilt.

Jagged lines across a tape: a seismogram.
"The earthquake that started the landslide was a 5.0 Earthquakes were happening all the time. There were probably a half-dozen magnitude 4-plus quakes every day, and a couple dozen 3-plus quakes.
"One day, as we were driving down of the mountain, we ran into an earthquake. It was a 4.9. You could see waves of distorted ground coming down the ridge and across the road, like ripples on a washboard. They moved right through the car. Shook the hell out of us."

A side view of St. Helens in hazy morning sunlight. A Rosenquist slide; Voight works through the sequence slowly, dissecting the avalanche, pointing out the moment when the blast began. The last Rosenquist frame shows the mountain vanishing behind a gray, crinkle-edged cloud.

A bearded man next to a tubular device that looks like a submarine's deck gun. "That's Dave Johnston, the survey geologist who was on Coldwater Ridge when it happened. He died."

An old man, backlit, going into a building.

"Harry Truman."
Truman, in his 80s, had refused to leave the lodge he ran on Spirit Lake when the Forest Service ordered him out.

Spirit Lake. The water is gray, choked with trees. In the background, behind a jumbled mass of rock and ash, St. Helens stands with half its top missing.
"The avalanche actually crossed the lake," says Voight. "Lifted the lake up on its shoulders, and went across. The lake didn't drain, but it's 200 feet higher than it used to be."

Trees, Voight's back, and the original mountain. "My camp above Maratta Creek. Before."

A field of ash. "After."
"How far is Maratta Creek from St. Helens?"
"Ten, 12 miles."
"If you had been there, would you have died?"
"When you were there, did you have any conception that you could die?"
A pause. "Yeah."
"Why were you so close? Why was Dave Johnston so close?"
Voight runs fingers through his hair. "There were lots of people in close," he says. "You had this volcano, and it was close to populated areas. There's a string of volcanoes up and down the coast—St. Helens, Rainier, Baker, Hood, Shasta. You had to see if this one was going to erupt.
"You're willing to take certain risks for certain purposes. We were interested in seeing pyroclastic flows being generated. They're not well understood.
"In the past, St. Helens would go active for decades at a time, so there's a good chance for more eruptions. There have been a dozen smaller eruptions since the big one. People are out there right now, going back on top. I've been back on top. Lava squeezing up like toothpaste. There's a bubble of lava in the crater as big as the Seattle Kingdome."

The crater. Rubbled sides pitch up steeply. Dust hangs where a small avalanche has just rolled into the basin. A man in a yellow slicker is taking a photograph.

"On top, you're within range. The helicopter pilot is in radio contact with a monitoring station below. Sometimes we'd be poking around, and the pilot would start revving the engines and give us a shot on the siren, and we'd say, ‘Good God, let's get the hell out of here!'"

Voight works the focus lever. The man in the slicker moves in and out of sharpness. "We're learning a lot," he says. "We can make measurements, and spot a trend, and know that an eruption will occur within a certain number of days. Every eruption is being predicted, and accurately.

"If we can understand today's deposits, we can look back into the past. We can look at the rocks and say, ‘This is a volcanic rockslide. This is an ancient horizontal blast.'"

Voight turns on the lights and packs up the projector.

"I've got five students working in Iceland," he says. "Two plates are pulling apart there. Magma oozes up where they split. We're studying the rift transform zone, looking at how the rift has jumped around in the last 10 million years or so.

"Iceland sits on the eastern edge of the North American plate. On the western edge, there's that goddam volcano."

Last Updated March 01, 1983