canuck
11-10-2004, 09:22 AM
might want to hold off on any trips for a while.
SEATTLE (AP) - Mount Rainier shook with a 3.2-magnitude earthquake, but scientists said Tuesday the quake was not related to recent rumblings at Mount St. Helens, its sister volcano 80 kilometres to the south.
The quake was centred 1.5 kilometres below the surface of Rainier's crater, said Bill Steele of the Pacific Northwest Seismograph Network at the University of Washington. "Directly under the volcano, that's a significant size," Steele said. One other 3.2-magnitude quake has been recorded at the mountain in the past 30 years: on Feb. 19, 2002.
Sunday's quake occurred within a cluster of 17 to 18 shallow temblors over several hours, he said.
Steele said quake activity at Rainier has increased over normal levels in recent weeks. Five quakes greater than magnitude 2.0 were recorded Oct. 25-31, he said.
Mount Rainier, which has been volcanically active for between a million and a half years, last erupted about 150 years ago and scientists say it's likely to erupt again at some point.
Rainier calmed down Monday and has been "blessedly quiet" since, he said.
Scientists are watching for continuing earthquakes near the volcano's surface and a particular type of seismic activity that results from fluid moving through rocks. Those clues might signal an eruption, Steele said.
Despite Mount St. Helens' notoriety, Rainier is considered the most hazardous of all Cascade Range volcanoes because it is closer to more populated communities, Steele said.
Mount St. Helens rumbled back to life Sept. 23, with shuddering seismic activity that peaked above magnitude 3 as hot magma broke through rocks in its path. Molten rock reached the surface Oct. 11, marking resumption of dome-building activity that had stopped in 1986.
St. Helens continued Tuesday to build its lava dome, with molten rock reaching the surface at the rate of about one large dump-truck load per second.
A more explosive eruption, possibly dropping ash within a 15-kilometre radius of the crater, is possible at any time, scientists have said.
SEATTLE (AP) - Mount Rainier shook with a 3.2-magnitude earthquake, but scientists said Tuesday the quake was not related to recent rumblings at Mount St. Helens, its sister volcano 80 kilometres to the south.
The quake was centred 1.5 kilometres below the surface of Rainier's crater, said Bill Steele of the Pacific Northwest Seismograph Network at the University of Washington. "Directly under the volcano, that's a significant size," Steele said. One other 3.2-magnitude quake has been recorded at the mountain in the past 30 years: on Feb. 19, 2002.
Sunday's quake occurred within a cluster of 17 to 18 shallow temblors over several hours, he said.
Steele said quake activity at Rainier has increased over normal levels in recent weeks. Five quakes greater than magnitude 2.0 were recorded Oct. 25-31, he said.
Mount Rainier, which has been volcanically active for between a million and a half years, last erupted about 150 years ago and scientists say it's likely to erupt again at some point.
Rainier calmed down Monday and has been "blessedly quiet" since, he said.
Scientists are watching for continuing earthquakes near the volcano's surface and a particular type of seismic activity that results from fluid moving through rocks. Those clues might signal an eruption, Steele said.
Despite Mount St. Helens' notoriety, Rainier is considered the most hazardous of all Cascade Range volcanoes because it is closer to more populated communities, Steele said.
Mount St. Helens rumbled back to life Sept. 23, with shuddering seismic activity that peaked above magnitude 3 as hot magma broke through rocks in its path. Molten rock reached the surface Oct. 11, marking resumption of dome-building activity that had stopped in 1986.
St. Helens continued Tuesday to build its lava dome, with molten rock reaching the surface at the rate of about one large dump-truck load per second.
A more explosive eruption, possibly dropping ash within a 15-kilometre radius of the crater, is possible at any time, scientists have said.