International Glaciospeleological Survey
Birth of a Glacier; Forms in Mouth of NW Volcano
11/09/2002
By VINCE PATTON, KGW Staff
The moonscape of the Mount St. Helens crater hides a secret. That perpetual layer of gray ash and rock disguises something completely unexpected.
Charlie Anderson bends down and rubs dirt away with his fingers, then scratches deeper. "Almost like refrigerator ice right down underneath this stuff," he says while tapping. "You don't have to dig very deep."
The ice is so thick it's forming into a glacier. In some places, the ice sits 500 feet thick. Anderson says, "It's the fastest growing glacier in the continental United States."
Anderson's investigations have helped prove it. He's a part-time geologist from Federal Way, Washington who has spent 100-thousand dollars of his own money over 20 years investigating the mountain. Each trip requires a special permit and an expensive helicopter ride in and out. Anderson has made the trip into the crater 138 times since 1980.
He and fellow geologists take measurements on top of and under the thick layer of ice. Wearing safety helmets and climbing gear, they climb down into caves forming under the ice.
"We're kind of limited because of the snow and because of the rockfalls that plugged some of the cave entrances," says fellow geologist Chris Behrens. "I want to be careful about that. I don't want
to cause a rockfall."
The geologists have mapped 2000 feet of tunnels under the ice around the volcano dome. The ice grows progressively thicker the deeper down they climb. In some spots it's little more than dense-packed snow. Lower, it becomes firn ice, and even deeper it reaches the true density of glacial ice.
Each time they enter the crater these explorers face unpredictable dangers every time they enter the crater. Rocks fall constantly from the crater's rim, 2000 feet above their heads. The landslides create an eerie sound that never disappears from the crater. "Some of the rocks are bigger than a Volkswagen," says Anderson.
The glacier is not just ice. Every year another mammoth layer of snow compacts and buries all the rocks that have fallen. After years of this cycle, layers of snow and rock and snow and rock form the glacier. Underneath it all in the caves, any of it could fall on the explorers' heads.
Aside from the obvious dangers of rockfalls and earthquakes in here, there's a hidden hazard of built-up of gas. Hydrogen sulfide and carbon dioxide can build up to lethal levels. In the deeper caves, the geologists carry special sensors with them to detect those gases.
In 1990, Anderson narrowly escaped the crater when steam eruptions began and spewed ash to 16-thousand feet in the air. "I was within probably 200 yards from where the rocks were flying at the time," says Anderson. "I just dove under some big rocks and just prayed."
The volcanic heat sprays out steam constantly around the crater; it's that heat which carves the caves from otherwise solid ice. And yet, says Anderson, "A lot of this ice never melts." Much of it stays frozen because those soaring crater walls face north and leave most of the glacier in shade.
Anderson marvels at what he's witnessing before his very eyes. "Nobody's seen a glacier from the very beginning accelerate so fast. It takes hundreds and hundreds of years. " But not here. And Charlie Anderson has had a front row seat the whole time. "I got to study it from the very beginning, which is neat," he says. "I love to study glaciers and volcanoes at the
same time!
USGS/Cascades Volcano Observatory, Vancouver, Washington
Mount St. Helens, Washington -
Glaciers and Glaciations
- Background and Information
- DESCRIPTION: Mount St. Helens Glaciers and Glaciations -- includes Ape Glacier ... Dryer Glacier ... Fraser Glaciation ... Forsyth Glacier ... Leschi Glacier ... Loowit Glacier ... Nelson Glacier ... Newest Glacier ... Shoestring Glacier ... Swift Creek Assemblage ... Swift Glacier ... Talus Glacier ... Toutle Glacier ... Wishbone Glacier ..
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The Newest Glacier |
From: USFS Volcano Review, Summer 2002, contribution by Charlie Anderson, Director of the International Glaciospeleological Survey
In the unique laboratory of Mount St. Helens, scientists that study glaciers and glacier caves are
observing and documenting a newly formed glacier. Over the last 21 years, snow, ice and rock
debris have accumulated behind the Lava Dome to an average depth of 100 meters (325 feet) thick.
The snow has been stacking higher each year compressing the past years' snow into a dense crystalline
ice body, as deep as 190 meters (600 feet). Giant cracks in the ice, called crevasses, and other flow
features, indicate that the ice body is transforming into a glacier. Scientists, known as Glaciospeleologists
have been studying the movement and growth of the glacier as it creeps around both sides of the Lava Dome,
flowing north.
Charlie is interview in an ice cave
Charlie is walking near the dome.
Date: Thursday, October 31, 2002 10:13 AM
Friday @ 11
Birth of a Glacier. Mt. St. Helens is hiding a secret. It’s the fastest growing glacier in the continental United States. Now you can journey where few are allowed. A Unit 8 In-Depth Report.
Watch tonight on News Channel 8 - Where the News Comes First.
Photos By Vince Patton
