February 9, 2016 - WASHINGTON STATE, UNITED STATES - A 2.9-magnitude earthquake hit just south of Mount St. Helens Monday morning, according to the U.S. Geological Survey.
The quake was recorded at 8:50 a.m.
The earthquake, according to the USGS, wasn't very strong. Only three people reported feeling it, as of 10:30 a.m.
It's the strongest earthquake in Washington in February. A 2.6-magnitude quake was reported Feb. 5 near Tacoma. - MyNorthwest.
Earthquakes that occurred before the May 1980 eruption of Mount. St. Helens may have been caused by magma being injected from one chamber to another.
Researchers said more tremors were observed in the area, which could hint of potential eruption. (Photo : Davgood Kirshot | Pixabay)
November 10, 2015 - PACIFIC NORTHWEST, UNITED STATES - The eruption of Mount St. Helens on May 18, 1980 has claimed 57 lives and caused serious damage to homes and infrastructure.
Now, scientists have revealed that the volcano could possibly erupt again in the future based on findings of a pioneering $3 million study of the volcano's plumbing system.
Geologists who studied the volcano have found a second enormous chamber lying between seven to 23 miles beneath the surface.
This massive pool of molten rock was found connected to a smaller chamber lying directly beneath the volcano.
How these two chambers are connected is helping scientists understand the sequence of events prior to the 1980 eruption, whose strength of explosion destroyed the topmost peaks of the mountain.
Matching the newly discovered magma reservoirs with earthquake data also sheds light on how the deadliest eruption in U.S. history occurred.
The researchers said that the series of tremors that occurred in the months leading to the 1980 eruption may have been caused by magma pumping from the lower to the upper chamber of the volcano, which caused the pressure inside the upper chamber to dramatically increase resulting in the deadly explosion.
"We can only now understand that those earthquakes are connecting those magma reservoirs," said Rice University seismologist Eric Kiser. "They could be an indication that you have migration of fluid between the two bodies."
Reporting the findings of their study at the annual meeting of the Geological Society of America in Baltimore, Maryland on Nov. 3, the researchers said that more tremors have been observed in the area suggesting that more magma is being injected.
"A cluster of low frequency events, typically associated with injection of magma, occurs at the northwestern boundary of this low Vp column," the researchers reported. "Much of the recorded seismicity between the shallow high Vp/Vs body and deep low Vp column took place in the months preceding and hours following the May 18, 1980 eruption. This may indicate a transient migration of magma between these two reservoirs associated with this eruption."
After the 1980 eruption, the volcano started to erupt again in 2004 but it fell silent in July 2008. Nonetheless, Mount St. Helens is still considered a high risk volcano and is closely monitored by the U.S. Geological Survey. The researchers said that their findings could offer a crucial early warning system of a potential eruption. - Tech Times.
Plinian column from May 18, 1980 eruption of Mount St. Helens. Aerial
view from southwest. Mount Adams is in the background (right).
Robert Krimmel photo May 18 1980
May 16, 2015 - U.S. PACIFIC NORTHWEST - Mount St. Helens caught science a little by surprise.
A volcano hadn't erupted on the United State mainland outside Alaska and
Hawaii since California's Lassen Peak in early 20th Century.
And modern science had yet to witness an eruption quite like St. Helens.
"I think this was a turning point in the way people approached these
kinds of potentially active, explosive volcanoes," said Mike Dungan, a
volcanologist with an office at the University of Oregon.
St. Helens didn't just erupt: it blew up.
The force of the May 18, 1980, eruption wasn't just vertical; it was
lateral, sending a side of the mountain rocketing down slope as a wall
of boiling mud and rock.
The eruption killed 57 people - and put scientists and policy makers on notice.
"It's only a matter of a short time - decades or something - before
another one of these things occurs," Dungan said. "A sector collapse
eruption like Mount St. Helens - it will happen again in Cascades."
Research at the University of Oregon is shedding new light on the cause of the explosion.
Geologists like PhD student Kristina Walowski are conducting research
into how ocean water seeps into offshore plates as they plunge deep into
the earth.
"What's really interesting is that water is really important because it
lowers the melting temperature of a rock and when that happens you can
create magma," she said.
Mount St. Helens viewed aerially from the northeast before the 1980
eruptive activity. Dashed line marks boundary of area removed by the May
18 blast.
"The water is really the key thing that causes the expansion, just like
when champagne comes jetting out of a bottle," said Paul Wallace,
professor geological science at UO. "It's a foamy material because of
the gas present in gas bubbles."
The May edition of Nature Geoscience published the findings by the Oregon team, funded by a National Science Foundation Grant.
"Ultimately the water that makes them so explosive is coming out of the
ocean," Wallace said. "And eventually as the plate moves like a conveyor
belt, it gets returned back down into the inside of the earth.."
WATCH: Eruption like Mount St. Helens - 'It will happen again in Cascades'.
"It's not like you're pouring cups of water into the interior of the
earth, right?" Walowski said. "There's a complicated set of reactions
and breakdowns where these rocks are changing shape, and releasing water
little by little by little."
So which of the Cascade volcanoes is next in line to erupt?
It's difficult to predict, but geologists are watching.
"We're really in the midst of a technology explosion when it comes to
monitoring volcanoes, using all kinds of things using remote sensing
instruments on satellites," Wallace said.
"Mount St. Helens is still the most frequent in the Cascades," Walowski
said, "and based on that, it may be the most likely to go again." - KVAL.
May 01, 2014 - SEATTLE, UNITED STATES- Magma levels are slowly
rebuilding inside Mount St. Helens, a volcano in Washington state that
erupted in 1980 and killed 57 people, although there was no sign of an
impending eruption, U.S. scientists said.
Visitors to the Coldwater Ridge Center look up at Mount St. Helens venting steam October 11, 2004. REUTERS/Andy Clark
The roughly 8,300-foot volcano erupted in an explosion of hot ash and gas on May 18, 1980, spewing debris over some 230 square miles and causing more than a billion dollars in property damage. Entire forests were crushed and river systems altered in the blast, which began with a 5.2 magnitude earthquake.
"The magma reservoir beneath Mount St. Helens has been slowly re-pressurizing since 2008," the U.S. Geological Survey said in a statement on Wednesday. "It is likely that re-pressurization is caused by (the) arrival of a small amount of additional magma 4 to 8 km (2.5 to 5 miles) beneath the surface."
The USGS said this is to be expected with an active volcano and does not indicate "the volcano is likely to erupt anytime soon."
The USGS, and the Pacific Northwest Seismic Network at University of Washington, closely monitor ground deformation and seismicity at the volcano. This summer, they will also measure its released gases and gravity field, measurements that can be used to monitor subsurface magma and forecast eruptions. - Yahoo.
