PLANETARY TREMORS: 2.9 Magnitude Earthquake Recorded Near Mount St. Helens, Washington - USGS!

A 2.9-magnitude earthquake was recorded near Mount Saint Helens Monday morning. © MyNorthwest

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.

GLOBAL VOLCANISM: Seismologists Watching Glacier Peak In Washington - After 4 Earthquakes In Just Under 4 Hours!

Two earthquakes - magnitude 3.1 and 3.5 - struck Wednesday afternoon near Glacier Peak within an hour of each other.
Two more smaller earthquakes struck just hours later. © Earthquake Tracker

November 27, 2015 - SEATTLE, UNITED STATES - Four earthquakes struck within hours of each other Wednesday afternoon near Glacier Peak in Washington.

The first two earthquakes registered at magnitudes 3.1 and 3.5. The first earthquake occurred at 12:11 p.m. The second registered roughly an hour later at 1:20 p.m. Then a third earthquake — a magnitude 1.6 — occurred at 2:33 p.m. And finally a fourth earthquake — a magnitude 1.4 — was registered at 3:44 p.m. All the quakes were recorded roughly 19-21 miles east-southeast of the town of Darrington.

Seth Moran, geophysicist at the University of Washington, tells KIRO Radio they're keeping a close eye on the area and continue to watch the seismic records. "Magnitude 3 earthquakes happen in Washington and Oregon a number of times per year," Moran said. "The one thing that makes these potentially interesting in a different way is they're somewhat close to Glacier Peak."

Glacier Peak (Photo: KING)

The quakes, about three miles from Glacier Peak, occurred where there haven't been a lot of magnitude 3 earthquakes in the past, according to Moran. "The last time there was a magnitude 3 in the vicinity was in 1991," Moran said.

However, there isn't a great network of seismic instruments in the area. There have been no reports of damage or injuries.


WATCH: Mount Rainier is considered the world's most dangerous volcano because of its size and how close it is to population centers, but there's another mountain you've probably never seen that's finally getting attention for the risks it poses.

According to the USGS, the last time Glacier Peak erupted was 1,100 years ago. Mount St. Helens and Glacier Peak are the only volcanoes in Washington state that have been explosive in the past 15,000 years. - My Northwest.

 

GLOBAL VOLCANISM: Could Mount St. Helens Erupt Again - Volcanic Tremors Hint Of Magma Being Injected?!

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.

GLOBAL VOLCANISM: Geologists - Hidden Cascades Volcano May Pose A Threat!

Glacier Peak (Photo: KING)

May 20, 2015 - SEATTLE, UNITED STATES - Monday marks the 35th anniversary of the eruption of Mount St. Helens that killed 57 people.

Mount Rainier is considered the world's most dangerous volcano because of its size and how close it is to the population centers of Tacoma and Seattle.

But there's another mountain you've probably never seen that's getting attention for the risks it poses to the Seattle area.

Unlike most of the volcanoes in the Cascade Mountains that are viewable from Interstate 5 or even Seattle, few people notice Glacier Peak. It lurks within in the northern Cascades in Snohomish County and has a record of violent, even extreme eruptions.

Jim Vallance a geologist at the Cascades Volcano Observatory, was a young field assistant on Mount St. Helens in the wake of the 1980 eruption. He remembers doing field work on St. Helens in 1979."It was quiet. You may remember if you were an old timer in the Northwest, that Spirit Lake was a blue body of water with cabins all around," said Vallance. "That all changed dramatically in 1980."

"As impressive as it was, Mount St. Helens was actually hundreds of feet shorter than Glacier Peak," Vallance points out. "The summit is right here."

Now his role at the observatory is dedicated to understanding Glacier Peak.

Every year's brief field season is on foot or with the help of pack mules to bring out more samples that lead to more understanding.

"I'm working on a giant four-dimensional puzzle. I'm trying to work out what happened in the past, when did it happen and how often," said Vallance.

When a volcano's glaciers melt during an eruption, it picks up massive amounts of fine dirt and debris. It becomes what's called a lahar.


WATCH: Mount Rainier is considered the world's most dangerous volcano because of its size and how close it is to population centers, but there's another mountain you've probably never seen that's finally getting attention for the risks it poses.

In the case of Glacier Peak, the geological record shows lahars reaching as far away as Mount Vernon, Burlington, Stanwood and Puget Sound by following the Skagit and Stillaguamish rivers.

But while some mountains, including St. Helens and Rainier, are heavily wired with sensors, there is but one lone seismometer on the west flank of Glacier Peak. That's about to change.

Next year, four boxes, each packed with a sensitive seismometer, global positioning antennas and other sensors, will be installed on Glacier Peak. The seismometers can tip off scientists to the first faint signals that magma is on the move.

"Most typical quakes around volcanoes are very small, very low magnitude," said Ben Pauk, a geophysicist who works with sensing technologies.

Then, as seen in the buildup to a 2004 eruption on Mount St. Helens, the quakes are constant.

"It's going to generate what's called volcanic tremor. So the ground is just constantly shaking," said Pauk. "And that gives us a really good indication of what type of eruption is going to occur."

Global positioning antennas measure when the mountain is actually starting to swell.

When could an eruption on Glacier Peak occur? There's no telling, said Vance, remembering that summer of 1979, when Mount St. Helens seemed so quiet.

"It could be this year or a thousand years," he said. - KSDK.

GLOBAL VOLCANISM: Eruption Like Mount St. Helens - "It Will Happen Again In Cascades"!

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.

GLOBAL VOLCANISM: USGS - Magma Rising In Washington State's Mount St. Helens Volcano!

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.

GEOLOGICAL UPHEAVAL: Bulletin Of The Seismological Society of America - 8,000 Seattle Buildings Face Landslide Threat In Big Quake!

October 23, 2013 - UNITED STATES - You already know Seattle is due for a devastating earthquake, but a new study shows one more thing to worry about: Landslides.

Ann Rice walks passed earthquake damage Thursday, March 1, 2001 in Tumwater, Wash. The Northwest
survived the region's strongest earthquake in a half-century with limited injuries and no permanent scars.
Damage estimates hit $2 billion Thursday as experts examined buildings, bridges, dams and roads.
(AP Photo/The News Tribune, Dean J. Koepfler)

Published Tuesday in the Bulletin of the Seismological Society of America, the study found that damage from earthquake-triggered landslides will be worse and more widespread in Seattle than previously thought.

The study focused on the Seattle Fault, a 30-mile fracture that runs east-west through Seattle, under CenturyLink Field and over to Issaquah. Capable of inflicting mass damage, it's due for another rupture, but no one knows when.

"A major quake along the Seattle Fault is among the worst case scenarios for the area since the fault runs just south of downtown," said Kate Alltstadt, a University of Washington doctoral student and co-author of the study.

Why Seattle is particularly vulnerable to earthquake-triggered landslides: First, the city sits on a known earthquake
fault and a sedimentary basin that amplifies seismic waves. Secondly, Seattle is full of hills. The red areas
show landslide risk zones. (Not shown is amount of rain, which makes things worse).  Source: Kate Allstadt,
Art Frankel and John Vidale, from 2013 earthquake landslide funded by U.S. Geological Study.

Here's a textbook guide on types of earthquake sources near Seattle. The megathrust quake often called
"the big one" will come from the subduction zone. That's where the Juan de Fuca plate is squeezing under
the North American plate. The Seattle fault is also a source of potentially deadly "crustal" quakes,
due to their relative shallowness to the surface. Source: U.S. Geological Survey.

Then there's Seattle's rain and craggy topography, a recipe for landslides. Allstadt and the research team wondered: How would a magnitude 7.0 quake along the Seattle Fault affect the city's crumbly slopes?

Answer: Catastrophe. The study found that thousands of landslides would ravage Seattle's coastal bluffs and southern neighborhoods. More than a 1,000 buildings would be in hazard zones of collapsing hills, the study found. But that when the soil was dry.

A far worse threat loomed when hills were soggy. More than 8,000 buildings would be in potential danger if a major earthquake hit after a rainy spell.

Pioneer Square is pictured after a magnitude 7.1 earthquake hit Seattle in 1949. Eight people were killed.
(Photo: Seattle Post-Intelligencer, copyright MOHAI, 1986.5.2353)

Paul Riek is pictured checking his car in Pioneer Square to see if it starts after a magnitude 6.8 quake hit Seattle
and the region on Feb. 28, 2001. (AP Photo/Stevan Morgain)

"A lot of people assume that all landslides occur in the same areas, but those triggered by rainfall or human behavior have a different triggering mechanism than landslides caused by earthquakes, so we need dedicated studies," said Allstadt, who's also a seismologist with the Pacific Northwest Seismic Network.

The Seattle Fault last ruptured in 900 A.D., at an estimated magnitude 7.4. It wreaked geologic havoc, sending chunks of forest into Lake Washington. Seattle was not yet a city then, and the next rupture has the deadly potential to bring down thousands of homes.

When will this happen? One estimate puts the quake recurrence at every 750 years. Another says every 200 to 12,000 years. One thing is known: Seattle is due; the fault last ruptured more than 1,100 years ago. - Seattle PI.

PLANETARY TREMORS: Mini-Earthquake Swarm Continues Near Mount St. Helens - Geologists Says Not Directly Related To Nearby Volcano!

August 23, 2013 - UNITED STATES - Three earthquakes rattled an area northwest of Mount St. Helens on Friday, continuing what geologists say is a mini-swarm of earthquakes not related to the nearby volcano.

U.S. Geological Survey map shows location of the three quakes.

The latest quakes, on Friday, were a 3.7-magnitude quake at 2:38 p.m. Friday, followed by a 3.4 at 6:08 and a 3.1 at 6:12 p.m., according to the U.S. Geological Survey.

A report from the USGS on Friday said the quakes have been centered about 13 miles northwest of Mount St. Helens at a depth of about 8 miles. They were described as tectonic in origin and not directly related to the volcano.

The report said such earthquakes are common in areas around Mount St. Helens and Mount Hood. It said another mini-swarm of earthquakes also occurred about six miles southwest of Mount Hood.

Volcano-related seismic activity at the two volcanoes themselves were at normal background levels, the USGS said. - The Columbian.

PLANETARY TREMORS: Unshaken Complacency - North America Unprepared For A Cascadia Mega-Quake!

December 23, 2012 - UNITED STATES - People often remember the calm, the quiet, how normal everything seemed before a disaster.  In Clark County, they might remember grabbing a cup of coffee at Starbucks by Esther Short Park, hanging out on the patio at Beaches by the waterfront, taking a bike ride along the Salmon Creek Trail -- before the shaking started.  During the long seconds of a magnitude 9.0 Cascadia earthquake, the soft loose soils along the Columbia River could quickly convert to the consistency of liquid or quicksand.  Beaches, Who Song & Larry's, Joe's Crab Shack and other establishments could jiggle, shift and sink lopsided into the ground by a few inches or a few feet.  Buried water mains and sewer lines could crack, separate, or float to the surface, spilling their contents across roads, landscapes and waterways. Downtown, older brick-and-mortar buildings could shift and shake, shedding bricks and rooftops in piles of debris.  In the flash of a few minutes, pretty much all of Clark County would be likely to find itself without power, without reliable roads and without safe water. And it could stay that way for months.  On a normal late fall day in Vancouver, such devastation might seem unreal. But it's happened before -- across the globe, and also right here.

Then-Gov. Gary Locke inspects a fissure in Deschutes Parkway in Olympia after the magnitude 6.8 Nisqually quake in 2001. Worse damage is likely the next time the Cascadia fault ruptures off the Pacific coast -- the last Cascadia earthquake was a magnitude 9.0, more than 100 times as powerful as the Nisqually quake. Files/Associated Press.

What is a Cascadia quake? 
Just off the Pacific coast -- about 50 miles out to sea, and stretching from Northern California to British Columbia -- a 700-mile fault marks where the Juan de Fuca geologic plate is sliding under the North America plate. The process, which started about 20 million years ago, is pushing North America over Juan de Fuca at a rate of about 1.5 inches a year.  Rock from the dipping, or subducting, plate melts as it moves under the continent, feeding the volcanic arc that includes Mount St. Helens, Mount Hood and Mount Rainier.  Pressure also builds up along the fault. The plates don't move smoothly but tend to stick and lock against one another, resisting movement until the fault suddenly slips, creating deep and potentially very deadly earthquakes.  There's no way to predict exactly when the fault will move again. The last time it happened was just over 300 years ago -- when the entire 700-mile stretch slipped in the span of about five minutes, creating a magnitude 9.0 earthquake and a massive tsunami recorded in Japanese history as occurring Jan. 26, 1700.  Geologists have uncovered evidence of similarly sized quakes in the region in 1310 AD, 810 AD, 400 AD, 170 BC and 600 BC. There may have been more, but it can be hard to find evidence of earthquakes in the rock record.  Because of that, scientists continue to debate how often the fault ruptures. Some think it happens about every 500 years; others think it's more like every 250 years.  "Nothing is for sure," said Tim Walsh, chief hazard geologist at the Washington State Department of Natural Resources. "But we've gone past that 250-year time scale already."

Potential for earthquake damage across Clark County.

The risks 
The Clark County Hazard Identification Vulnerability Analysis, put out by Clark Regional Emergency Services Agency, called the threat of a dangerous earthquake "the hazard of greatest risk to Clark County," more threatening than a flood, wildfire or volcanic eruption.  The analysis ranks the 25-year probability, vulnerability and risk rating for a strong quake -- if not a full 9.0 Cascadia quake -- as high.  There are three categories of earthquakes, all of which occur here.  • Shallow or crustal quakes happen along faults near the surface, up to about 10 miles deep. Such faults include the Mount St. Helens Seismic Zone, the Lacamas Creek Fault and the Portland Hills Fault. Shallow faults can trigger by themselves, or could be triggered by deeper earthquakes created through plate tectonics.  • Interplate quakes happen when one geologic plate affects another, such as parts of Juan de Fuca melting and scraping beneath the North America plate. Those quakes tend to be deeper, perhaps 30 miles below Earth's surface.  • Subduction zone earthquakes happen when plates stick and then suddenly slip against one another at plate boundaries, such as the Cascadia fault.  Every year, the Pacific Northwest Seismograph Network records about 2,000 earthquakes in Washington and Oregon. Most are shallow quakes with magnitudes of less than 3.0.  Larger shallow quakes are far less frequent but can be dangerous. The strongest shallow quake recorded since white settlers came to the region was an estimated magnitude 7.4 back in 1872. It was felt in Oregon, Idaho and Washington. More recently, the "Spring Break Quake" on March 25, 1993 -- a shallow magnitude 5.6 centered southeast of Portland -- caused $28 million in damage.  Interplate quakes can cause even more damage. On Feb. 28, 2001, the magnitude 6.8 Nisqually earthquake centered 32 miles beneath the Puget Sound region killed one and injured 700, creating between $1 billion and $4 billion in damage.  Scientists think both of those types of earthquakes happen at a rate of about one per 50 years in the Pacific Northwest.  Then there's a Cascadia quake, which would be a subduction zone earthquake. It's hard to tell how much damage a 9.0 quake like that would cause, but a report by the Department of Natural Resources suggests the damage could go well into billions of dollars and injure or possibly kill thousands of people.  "Big picture for a Cascadia (earthquake) … we're definitely looking at years before we're made whole again," said John Wheeler, emergency management coordinator at CRESA. "If you look at (Hurricanes) Katrina and Sandy, at the Japanese earthquake -- the damage from those is very similar to what we could experience in the Pacific Northwest." - The Columbian.