Kitana85
10-02-2004, 10:20 AM
Pressure Building Again Inside St. Helens
2 hours, 18 minutes ago
By DAVID AMMONS, Associated Press Writer
MOUNT ST. HELENS, Wash. - Mount St. Helens quieted down after spewing a plume of steam and ash — but only briefly. Within hours of the eruption Friday, seismic readings suggested pressure was building again inside the volcano, which had been dormant for 18 years.
It began rumbling last week, set off by small earthquakes occurring as often as three or four times a minutes, and scientists said there could be more steam eruptions soon.
Friday's eruption, described by government scientist Jeff Wynn as a "throat-clearing," was the sleeping giant's first since 1986. On May 18, 1980, Mount St. Helens blew its top with such force that 57 people lost their lives.
The volcanic burp cast a haze across the horizon as the roiling plume rose from the nearly 1,000-foot-tall dome. After about 20 minutes, the mountain calmed and the plume dissipated.
"It was such a thrill!" said Faye Ray, a retired school teacher who watched from an observatory near the mountain. "I just felt we would see something today and we did."
The ash appeared to pose no threat to anyone, but scientists warned that people living southwest of the mountain might notice a dusting on their cars. There was no sign of lava.
The earthquakes started Sept. 23 and grew steadily stronger, finally reaching a magnitude of 3.3 Thursday and Friday. After the eruption, they stopped for several hours, said Wynn, of the U.S. Geological Survey
Then, the tremors resumed, hitting a one-per-minute pace, said Bill Steele at the University of Washington seismic laboratory. A couple exceeded magnitude 2.
A few more steam explosions are likely, Steele said, "until enough debris is cleared, and then there is a significant chance that lava could be extruded at the surface."
Tom Pierson, a USGS geologist, said officials will monitor the site "on a very intense scale until we can determine that the thing has really gone back to sleep."
Scientists had not been expecting anything like the mountain's devastating eruption in 1980, which coated much of the Northwest with ash and obliterated the top 1,300 feet of the mountain. It now stands 8,364 feet.
Few people live near the mountain, the centerpiece of the Mount St. Helens National Volcanic Monument in the Gifford Pinchot National Forest, about 100 miles south of Seattle. The closest structure is the Johnston Ridge Observatory, about five miles from the crater.
"It wasn't lava-y, so I wasn't scared," said Lorain Weatherby, who was working a snack bar down the road from St. Helens. "It was like a big white cloud."
Mike Fergus, a spokesman with the Federal Aviation Administration (news - web sites) in Seattle, said the plume had reached 16,000 feet in altitude.
Alaska Airlines canceled five flights scheduled to take off from Portland International Airport in Oregon, but quickly resumed its normal schedule, said spokesman Sam Sperry.
hate to live there now
2 hours, 18 minutes ago
By DAVID AMMONS, Associated Press Writer
MOUNT ST. HELENS, Wash. - Mount St. Helens quieted down after spewing a plume of steam and ash — but only briefly. Within hours of the eruption Friday, seismic readings suggested pressure was building again inside the volcano, which had been dormant for 18 years.
It began rumbling last week, set off by small earthquakes occurring as often as three or four times a minutes, and scientists said there could be more steam eruptions soon.
Friday's eruption, described by government scientist Jeff Wynn as a "throat-clearing," was the sleeping giant's first since 1986. On May 18, 1980, Mount St. Helens blew its top with such force that 57 people lost their lives.
The volcanic burp cast a haze across the horizon as the roiling plume rose from the nearly 1,000-foot-tall dome. After about 20 minutes, the mountain calmed and the plume dissipated.
"It was such a thrill!" said Faye Ray, a retired school teacher who watched from an observatory near the mountain. "I just felt we would see something today and we did."
The ash appeared to pose no threat to anyone, but scientists warned that people living southwest of the mountain might notice a dusting on their cars. There was no sign of lava.
The earthquakes started Sept. 23 and grew steadily stronger, finally reaching a magnitude of 3.3 Thursday and Friday. After the eruption, they stopped for several hours, said Wynn, of the U.S. Geological Survey
Then, the tremors resumed, hitting a one-per-minute pace, said Bill Steele at the University of Washington seismic laboratory. A couple exceeded magnitude 2.
A few more steam explosions are likely, Steele said, "until enough debris is cleared, and then there is a significant chance that lava could be extruded at the surface."
Tom Pierson, a USGS geologist, said officials will monitor the site "on a very intense scale until we can determine that the thing has really gone back to sleep."
Scientists had not been expecting anything like the mountain's devastating eruption in 1980, which coated much of the Northwest with ash and obliterated the top 1,300 feet of the mountain. It now stands 8,364 feet.
Few people live near the mountain, the centerpiece of the Mount St. Helens National Volcanic Monument in the Gifford Pinchot National Forest, about 100 miles south of Seattle. The closest structure is the Johnston Ridge Observatory, about five miles from the crater.
"It wasn't lava-y, so I wasn't scared," said Lorain Weatherby, who was working a snack bar down the road from St. Helens. "It was like a big white cloud."
Mike Fergus, a spokesman with the Federal Aviation Administration (news - web sites) in Seattle, said the plume had reached 16,000 feet in altitude.
Alaska Airlines canceled five flights scheduled to take off from Portland International Airport in Oregon, but quickly resumed its normal schedule, said spokesman Sam Sperry.
hate to live there now