Dwight “Rocky” Crandell, one of the geologists who correctly predicted that Mount St. Helens would erupt, died April 6 at a Wheat Ridge hospice. He was 86.
A service will be held at 3 p.m. Saturday at Jefferson Unitarian Church, 14350 W. 32nd Ave. near Golden.
The prediction by Crandell and his colleague Don Mullineaux in 1978 that Mount St. Helens would erupt within 20 years came true two years later. The biggest eruption of the volcano, 150 miles southeast of Seattle, occurred in May 1980, killing 57 people.
“Rocky had a worldwide reputation for his work” in studying the history of volcanoes, said a former colleague, Dan Miller of Battle Ground, Wash.
“He was absolutely the best geologist, an incredibly good observer, and had great interpretative skills,” in being able to find out where deposits came from and what they meant, Miller said.
Earlier geologists studying the behavior of volcanoes had paid attention only to hardened lava flows. Crandell and Mullineaux figured out that there were other indicators: that volcanoes also spew ash clouds and chunks of rock and cause mud flows.
Because of their work, they became pioneers in volcanic hazard analysis, Miller said.
They were the first to understand that “past behaviors of volcanoes are the best determinate for what will happen in the future,” he said.
“He was a very careful geologist, very observant, knowledgeable and meticulous, and came up with ideas,” Mullineaux said.
He said that he and Crandell told local authorities about their predictions for Mount St. Helens and steps were taken before the eruption to restrict many areas from visitors.
Crandell did most of his work in the Northwest during summers, said his daughter Margie Robinson of Wheat Ridge. He was stationed at the Denver office of the U.S. Geological Survey.
Dwight Crandell was born in Galesburg, Ill., on Jan. 25, 1923. He earned his undergraduate degree in geology at Knox College there and a doctorate in geology at Yale University.
A college professor dubbed him “Rocky,” a point Robinson said she never understood because “everybody else was studying rocks, too.”
Crandell joined the U.S. Geological Survey in 1951, first working in Pierre, S.D.
On Nov. 27, 1943, he married Marion Anderson, whom he met in the choir at Knox. She died in 2004.
In addition to his daughter, he is survived by another daughter, Jane Monserud of Seattle; three grandchildren; and one great-grandchild. He was preceded in death by his son, Thomas Dwight Crandell.
Virginia Culver: 303-954-1223 or vculver@denverpost.com
