Legendary Northwest volcanologist "Rocky" Crandell uncovered Mount Rainier's menacing past and warned of Mount St. Helens' eruption.

Share story

When newly minted geologist Dwight “Rocky” Crandell was assigned to map the Puget Sound lowlands southeast of Seattle in the early 1950s, conventional wisdom held that the landscape was shaped mainly by glaciers.

But the sharp-eyed Dr. Crandell began filling his notebooks with observations of what appeared to be deep layers of mud underlying towns from Enumclaw to Auburn. Over several years, the U.S. Geological Survey (USGS) scientist tracked the mud to its unexpected source: High on the flanks of Mount Rainier.

The evidence Dr. Crandell and his partner, Don Mullineaux, pieced together proved the volcano’s summit had collapsed 5,600 years ago, unleashing a landslide so massive it flowed all the way to Puget Sound and filled nearby valleys with a slurry up to 400 feet deep.

The realization that such an event could happen again, with hundreds of thousands of people now populating Rainier’s fringes, shaped much of Dr. Crandell’s subsequent career.

Most Read Local Stories

Unlimited Digital Access. $1 for 4 weeks.

He and Mullineaux pioneered the approach used today to evaluate the hazards posed by volcanoes. Two years before Mount St. Helens’ 1980 blast, they warned that the restless volcano was primed to erupt. Before and after the eruption that claimed 57 lives, Dr. Crandell and Mullineaux worked around the clock in shifts to brief public officials, from then-governor Dixy Lee Ray to President Carter.

Dr. Crandell died Monday (April 6) of a heart attack at a hospice in Wheat Ridge, Colo. He was 86.

“He really was a giant in the field of volcanology in the Pacific Northwest,” said Dr. Crandell’s daughter Jane Crandell Monserud, of Seattle.

Dr. Crandell collected rocks as a child in Illinois, but he didn’t get the nickname Rocky until his first college field trip in 1941. He was a lieutenant in an Army mortar platoon in Germany during World War II and earned a doctorate at Yale after the war. His first job was with the USGS office near Denver, where he was based throughout his career.

Before Dr. Crandell’s work on Rainier, no one realized the picturesque volcano had such destructive potential, said former USGS volcanologist Dan Miller, who started working with the fledgling volcano team in the early 1970s.

Miller credits the breakthrough to Dr. Crandell’s skill for geologic observation and his open-minded way of considering all possible explanations. “It was a brilliant piece of detective work.”

While Dr. Crandell and Mullineaux were scouring rural Pierce County for evidence of Rainier mudflows, they began to find puzzling layers of volcanic ash that they eventually traced to Mount St. Helens. They embarked on a detailed study of the younger volcano’s violent past, resulting in a 1978 report that warned of a likely eruption within the next 20 years.

Miller spent time with the two veterans at their field camp on the shore of Spirit Lake, where days began with a dip and ended with gin and tonics under the stars. The hours in between were grueling.

“Rocky was a consummate field geologist,” Miller said. “He was willing to hike miles and miles to get to an outcrop, and go back day after day.”

Most early volcanologists only paid attention to hardened lava flows. But volcanoes can also spew ash clouds, rain chunks of rock and let loose mud flows and the searing mixtures of gas and rock called pyroclastic flows. Dr. Crandell and Mullineaux mapped all of those deposits, giving birth to the field now called volcanic hazard analysis, which looks at everything a volcano has done in the past to predict how it’s likely to behave in the future.

“That was really Rocky’s idea,” Mullineaux said. “It’s now used around the world, but when we were making the first map, nothing else like it existed.”

As a result of volcano-hazard mapping, several valleys downstream of Mount Rainier are now equipped with mudflow-warning systems. Some cities restrict development in vulnerable areas, and others hold regular evacuation drills.

Dr. Crandell and Mullineaux drew some criticism after Mount St. Helen’s cataclysmic eruption. A few victims’ families claimed the USGS scientists didn’t press hard enough for larger exclusion zones.

But the boundaries were set by public officials, and there was scant indication in St. Helens’ history that it would explode with such fury, Miller said.

Dr. Crandell retired a few years after the St. Helens eruption, partly to make way for young scientists. But he continued to do unpaid field work for another decade.

After his wife, Marion, suffered a brain injury in an automobile accident, Crandell devoted much of his time to her, said his daughter Margie Robinson, of Wheat Ridge, Colo. Mrs. Crandell died in 2004. Two years ago, Dr. Crandell visited Mount Rainier with his daughters to scatter her ashes. They also made a stop at Mount St Helens’ visitor center.

Rangers and staff came from across the park to meet the man whose work remains the bedrock of volcanology in the Northwest.

“You should have seen the commotion,” Monserud said. “Dad was greeted like a rock star.”

In addition to his two daughters and their husbands, Dr. Crandell is survived by three grandchildren and one great-grandchild. His son, Tom, died in a river-rafting accident in 1965.

A service will be held April 18 at Jefferson Unitarian Church in Golden, Colo.

Sandi Doughton: 206-464-2491 or sdoughton@seattletimes.com