Infernus
2004-10-01, 04:10 PM
OH NOES!
OH NOES! (http://www.cnn.com/2004/TECH/science/10/01/mount.st.helens/index.html)
VANCOUVER, Washington (CNN) -- Mount St. Helens began blowing a large cloud of smoke and steam Friday afternoon following a week in which scientists have closely monitored the volcano.
Officials placed the region around the mountain on a volcanic advisory on Wednesday.
The advisory that was issued is the third of four levels -- with the fourth being eruption.
The volcanic dome within the crater of the mountain has moved about three inches since Monday, according to U.S. Geological Survey geologist John Major.
Friday's event was described as a small explosion by geologist Tom Pierson. It could be the first of larger events, including an eruption, or it could be the end of a recent pattern of activity.
Late last week, seismologists began recording "swarms" of earthquake activity from the volcano.
The activity increased last weekend, and the Cascades Volcano Observatory scientists reported three to four quakes a minute with largest measuring 3.3.
Scientists reported some fracturing to the glacier; however, no cracking was detected on the outside of the crater.
"The cracking is much less cracking than past events in 1980, 1986, but the seismic pattern is similar," Major said. "It looks like something similar to 1984, 1985, and 1986 dome-building eruptions."
Thermal imaging is tracking changes in the lava dome and the side of the volcano for signs that magma might be moving in the mountain.
"The one thing that can not be ruled out is an eruption accompanied by a small explosion," said Elliot Endo, scientist in charge at Cascades Volcano Observatory.
Scientists continue to monitor the activity.
While an eruption could ooze magma within the crater, the larger concern is that it would send up a cloud of ash that would be spread by the wind and could become an aviation hazard, scientists have said.
Scientists do not expect a repeat of the 1980 eruption.
With an earthquake measuring a magnitude of 5.1, Mount St. Helens erupted on May 18, 1980. The north face collapsed in a massive rock debris avalanche.
The nine-hour eruption blew over or killed nearly 230 square miles of forest and sent a mushroom cloud of ash thousands of feet into the sky. That eruption killed 57 people.
Although some areas around the mountain have been closed to climbers and hikers this week, the visitor center just five miles away remains open.
OH NOES! (http://www.cnn.com/2004/TECH/science/10/01/mount.st.helens/index.html)
VANCOUVER, Washington (CNN) -- Mount St. Helens began blowing a large cloud of smoke and steam Friday afternoon following a week in which scientists have closely monitored the volcano.
Officials placed the region around the mountain on a volcanic advisory on Wednesday.
The advisory that was issued is the third of four levels -- with the fourth being eruption.
The volcanic dome within the crater of the mountain has moved about three inches since Monday, according to U.S. Geological Survey geologist John Major.
Friday's event was described as a small explosion by geologist Tom Pierson. It could be the first of larger events, including an eruption, or it could be the end of a recent pattern of activity.
Late last week, seismologists began recording "swarms" of earthquake activity from the volcano.
The activity increased last weekend, and the Cascades Volcano Observatory scientists reported three to four quakes a minute with largest measuring 3.3.
Scientists reported some fracturing to the glacier; however, no cracking was detected on the outside of the crater.
"The cracking is much less cracking than past events in 1980, 1986, but the seismic pattern is similar," Major said. "It looks like something similar to 1984, 1985, and 1986 dome-building eruptions."
Thermal imaging is tracking changes in the lava dome and the side of the volcano for signs that magma might be moving in the mountain.
"The one thing that can not be ruled out is an eruption accompanied by a small explosion," said Elliot Endo, scientist in charge at Cascades Volcano Observatory.
Scientists continue to monitor the activity.
While an eruption could ooze magma within the crater, the larger concern is that it would send up a cloud of ash that would be spread by the wind and could become an aviation hazard, scientists have said.
Scientists do not expect a repeat of the 1980 eruption.
With an earthquake measuring a magnitude of 5.1, Mount St. Helens erupted on May 18, 1980. The north face collapsed in a massive rock debris avalanche.
The nine-hour eruption blew over or killed nearly 230 square miles of forest and sent a mushroom cloud of ash thousands of feet into the sky. That eruption killed 57 people.
Although some areas around the mountain have been closed to climbers and hikers this week, the visitor center just five miles away remains open.