Volcanic rock has flowed to the surface of Mount St. Helens' crater, creating a new lava dome after weeks of seismic activity, a geologist said Tuesday.
Scientists had known for days that magma or molten rock was nearing the surface, as a bulge grew on the south side of the existing 1,000-foot lava dome and the increasingly hot rock gave off steam as it met &to=http:// english.pravda.ru/sport/2002/12/24/41261.html ' target=_blank>water and ice in the crater. The bulge is now considered a new lava dome, the scientists said.
"Now that we have new lava at the surface, we're comfortable saying" that dome-building has resumed at the volcano, U.S. Geological Survey geologist Tina Neal said, says ABC News.
According to Reuters, magma from deep below the mountain, located about 100 miles (160 km) south of Seattle, has pushed up the lava dome that formed in the crater after the 1980 eruption by 250 feet (80 metres).
Small &to=http:// english.pravda.ru/war/2003/04/01/45344.html ' target=_blank>earthquakes also continued to rattle the crater every five to 10 minutes, the USGS said, and gas-sensing flights have detected sulphur dioxide and carbon dioxide indicating the presence of magma.
Following its 1980 &to=http:// english.pravda.ru/region/2002/06/03/29588.html ' target=_blank>eruption, Mount St. Helens continued to belch lava, steam and ash until 1986, forming a lava dome in the crater created by the eruption.
"As a result of the intense unrest of the past two weeks and yesterday's observations, we infer that magma is at a very shallow level, and perhaps at the surface,' the USGS said.