Seismo Blog

On Monday morning (April 10) the Pacific Northwest Seismic Network (PNSN) was buzzing with activity, but not seismic activity. Network employees were sporting PNSN t-shirts and there were numerous outside officials wearing splashes of University of Washington purple. Reporters from The Seattle Times, KIRO News, the UW Office of News and Information, and more where crowded into the small lab room, surrounded by recording equipment. The lab room itself, with its old school, drum seismograms, was accessorized with extra monitors, a podium, and a clean, purple tablecloth covering the long table, normally cluttered with various earthquake demonstrations. 

What was the occasion? The Seismic Network hosted a press conference to announce the rollout of a new version of the earthquake early warning (EEW) system, ShakeAlert, which is now fully integrated across the entire West Coast of the United States. Speakers included the Dean of the UW College of the Environment, Lisa Graumlich, Dave Applegate and Doug Given from the United States Geological Survey, U.S. Representative Derek Kilmer, Washington State Seismologist, John Vidale, Maximilian Dixon from the Washington State Emergency Management Division, and Dan Ervin, chair of RH2 Engineering.

John Vidale shows an example of the ShakeAlert interface during a test warning. Photo credit: Kyla Marzewski.

Previously the EEW system in the Pacific Northwest was detecting earthquakes and issuing warnings to a beta test group, but the warnings were not being utilized. Now, while the system is not yet ready to send alerts to the public, warnings issued to pilot users will be used to test earthquake response systems. Users include RH2 Engineering in Bothell, WA, which will use the alerts to secure municipal water and sewer systems, and the Eugene Water and Electricity Board in Oregon, where alerts will be used to lower canal water levels above a residential area and turn off turbines at a power plant.

While the release of the updated system marks a large step forward for West Coast earthquake early warning, there is still more work to be done to allow the system to reach its full potential. Both Applegate and Given emphasized that the system only has about half the funding needed in terms of annual support. The development of the system has so far been funded by a combination of public and private grants, including support from the Gordon and Betty Moore Foundation, Amazon Catalyst, and Puget Sound Energy.

“Federal investment in science matters,” said representative Derek Kilmer.

Kilmer believes that Monday’s press conference highlights the value of the EEW system. He hopes that Congress will realize the benefits of having an EEW system across the West Coast and respond. Additional funding will go towards installing new earthquake-recording stations, improving telecommunications between stations and network computers, continued testing of the system, and hiring new staff.

Currently, the system only includes 700 of the 1700 stations needed to cover all the hazards and populations on the West Coast. While the EEW system can move forward with the existing stations, earthquakes in some places, for example parts of Eastern Washington, will be detected less quickly than with the full station set or not at all. Unfortunately, installing new stations is not like “planting flowers” reported Given. Not only do new stations cost money, getting permits to put stations on private, state, and federally owned land is time consuming. 

Another critical component needed to expand the system to be able to issue public alerts is education. Receiving a warning on your cellphone is not useful unless you know what the alert means and how to respond. While there is no funding for education yet, reported Dixon, the ultimate goal of EEW education is for the public to be able to react to warnings with a practiced, automatic response.

Despite the fact that a fully-fledged West Coast EEW system still requires more time, work, and funding, all the press conference speakers emphasized the utility of having earthquake warnings.

“(The earthquake risk on the West Coast) cannot be overstated,” stressed Given.

The EEW system will save lives, preserve infrastructure, and mitigate the loss of productivity post-quake. The release of the West Coast integrated system marks a milestone in earthquake preparedness.

Other articles about the West Coast early warning system:

Next ETS Expected any time now

January 24, 2017

by Steve Malone

Already over and then going again. Back-to-back ETS and finally over as of Apr 6.

Another Seahawks game experiment - Jan 7

January 6, 2017

by Steve Malone

Seahawks fans shake up the PNSN instruments.... again.
This Thursday, 50 million people around the world will drop, cover, and hold on for the 8th Annual Great ShakeOut, the largest earthquake drill in the world. This year at the PNSN, our motto is “drop, cover, hold on, and do something else too". We are thinking about other ways that we can enhance our preparedness for a major earthquake. This week on the SeismoBlog, we are outlining a few other strategies to supplement this year’s drill.

Cascade Volcano Seismology - a Tutorial

October 5, 2016

by Steve Malone

A newly modified tab on each volcano page gives a nice overview of each's earthquake history. Here is an introduction and some hints for interpreting these plots.

iMUSH: Adventures in the Field

September 12, 2016

by Lauren Burch

Seismology graduate student Mika Thompson shares a thrilling tale of wasps, fallen trees, and other impediments to science.

The Long Trek to MH09

September 8, 2016

by Shelley Chestler

Sometimes uninstalling a seismic monitoring station doesn't go quite as planned. Here is tale of my team's first attempt to take out a particularly stubborn station for the iMUSH (Imaging Magma Beneath St. Helens) project:
Both the Cascade Mountains and the Olympic Mountains are products of subduction, but not all mountain ranges are created in the same way.

Another debris flow avalanche at Mount Baker

June 15, 2016

by Steve Malone

Seismic signals on May 25 are evidence for the size and timing of yet another on of these avalanches.

All the mountains, oceans, and islands on Earth exist because of plate tectonics. Different plate boundaries produce different geologic features: divergent boundaries spread apart to form mid-ocean ridges and rift valleys, transform boundaries slide past one another to form strike-slip faults like the San Andreas, and convergent boundaries collide to form tall mountains, deep trenches, and volcanoes. This type of plate boundary is responsible for the numerous volcanic arcs around the Pacific Rim (often called the “Ring of Fire”), and formed our iconic Cascade Volcanoes. Here in the Pacific Northwest, the Juan de Fuca plate is subducting beneath the North American plate along a convergent plate boundary called the Cascadia Subduction Zone (CSZ). Subduction zones like this are the only fault systems capable of producing very large megathrust earthquakes, but they only do so occasionally - over the last 100 years, there have been 84 earthquakes of magnitude 8.0 or greater worldwide, and only 4 of them were greater than an M9.

 


The simplest answer to the question “Will there be another large earthquake on the CSZ?” is yes. However, the question of “when” is much more difficult to answer. Seismologists don’t know exactly when the next large earthquake will occur on the CSZ, but we do have a good picture of when they have happened over the past 10,000 years. If we divide 10,000 years by the number of ~M9 earthquakes found in that time period, the average recurrence rate for M9 earthquakes along the CSZ is roughly 550 years. We are 316 years past the last great CSZ earthquake in 1700, and we estimate that there is about a 15 % chance that an M9 will occur on this fault within the next 50 years. However, research on submarine landslide deposits shaken loose by big earthquakes indicate that M8+ earthquakes occasionally strike off the coast of Oregon in between “full rip” M9 events. This research suggests that there is a greater probability of reoccurence of a great earthquake in Southern Oregon than off the Washington coast, but there is not a consensus within the geophysical community as to specifically how much greater the hazard is.

One is a guess, and the other is an educated guess.
Earthquakes happen on faults, but where are the faults in Oregon and Washington? The new "Display Faults" tool on the PNSN Recent Events map can help you explore the locations of faults in the Pacific Northwest.

Exotic Events (not erotic events)

April 1, 2016

by Steve Malone

Seismically recorded non-earthquakes now have their own page at the PNSN.

Negative depth earthquakes?

March 30, 2016

by Steve Malone

Why do some earthquakes in our list have negative depths now?

Explosion "Earthquakes"

March 10, 2016

by Steve Malone

Two recent large explosions generated acoustic waves recorded on seismographs.

West Coast Earthquake Early Warning System on the Horizon

February 9, 2016

by Shelley Chestler

Last week the White House hosted the first ever Earthquake Resilience Summit. One of the main goals of the meeting was to discuss the potential for fully funding a west coast earthquake early warning system.

Back-to-back ETS events, maybe

February 6, 2016

by Steve Malone

Following the recent "standard" northern Washington ETS another has apparently started heading south toward Oregon.

Slow Earthquake Trembles beneath Vancouver Island

January 7, 2016

by Shelley Chestler

Did you know that there is a type of earthquake that happens so slowly that we can’t feel it? One of these slow earthquakes is happening under Vancouver Island and northern Washington right now!

A Perspective on Tremor Activity

January 7, 2016

by Aaron Wech

With tremor activity occurring in the Pacific Northwest, it's important to provide perspective.

Don't Sweat the Little Ones

December 14, 2015

by Shelley Chestler

The recent earthquakes around the Puget Sound are probably not indicative of the “big one.”

A new look for pnsn.org

December 4, 2015

by Jon Connolly

The new pnsn.org website aims to provide a better user experience for all devices, prioritize features, and provide robust availability during a seismic event.
The July 2015 New Yorker article “The Really Big One,” by Kathryn Schulz, shook up the Pacific Northwest (PNW) more than any earthquake has since the Magnitude-6.8 Nisqually earthquake in 2001. In the article’s most dooming statement, the head of the Cascadia FEMA division was quoted saying, “everything west of I-5 will be toast.” This assertion scared the living daylights out of PNW residents, creating a sense of terror and hopelessness that was the antithesis of what the article meant to do: to spur the region into preparing for this potentially devastating event.

Unusual earthquake swarm south of Bend, OR

October 23, 2015

by Steve Malone

A somewhat unusual earthquake swarm started early on Oct 22, 2015 in an area about 65 km (40 miles) southwest of Bend, OR (25 km WSW of La Pine, OR). 36 events have been detected and located by the PNSN as of noon on Oct. 23, the largest only Magnitude 2.5. This ongoing swarm is in the same area that had similar swarms in 2001 and 2012 and is likely just the same sort of thing taking place again. For more details and updates....

How big was that earthquake?

September 24, 2015

by Steve Malone

Determining an earthquake's size seems to often result in different and inconsistent estimates. The "Magnitude" of an earthquake can be determined by several different methods, all of which should have some relationship to one another and, at least be consistent one earthquake to another. Unfortunately that's often not the case. PNSN seismologists spend lots of time estimating (measuring and calculating) earthquake magnitudes and end up discussing (arguing over) different techniques and complaining (whining) about inconsistencies and criticizing (belittling) certain results. Recently some effort is being made to try and refine (improve) our standard, routine ways of determining magnitude. We are starting to upgrade our published catalog with these "improved" magnitude estimates so you may see these estimates change from what was in the catalog before. Don't worry. The earthquakes have not changed, just our estimate of how big they are. For the gory details of how this is being done......

Summer rockfall time, yet again

August 21, 2015

by Steve Malone

With hot dry weather it is not surprising that the seismic records for volcano stations show lots of signals consistent with rockfall/avalanches and other exotic seismic events. In fact it is a bit of a surprise that we have not seen more and bigger such events this summer........ so far. Recent activity at Mount Rainier has included a debris flow (probably related to a jökulhlaup) and a moderate sized rockfall from high on the southwest side of the volcano. For some of the seismic details.....