RAC Meeting 2008

 Meeting Materials/Presentations:

Minutes of ANSS Pacific Northwest Regional Advisory Committee 

27 May 2008 
minutes prepared by Tom Yelin 
 
The meeting was held at the University of Washington Seattle campus, in the 
University of Washington Club facility (formerly the Faculty Club).  It began at 
approximately 10:10 AM and ended at about 2:10 PM (with a brief break for 
lunch). 
 
Please see bottom of page for the list of attendees. 
 
Paul Bodin began with a report on the status of the PNSN, including progress 
made in replacement of aging network infrastructure and an increase in the 
number of permanent stations, both broad band and strong motion (see for 
example the slides labeled “New Stations” and “Advances” in the PDF version of 
the Power Point presentation. 
 
After this status report, specific topics were introduced and discussed in varying 
length and detail.  Because Craig Weaver had to leave by 12:30, John Vidale 
rearranged the agenda to begin with the topics about which Craig had 
information. 
 
Use of ANSS products
 
The discussion focused on what was learned from the Sound Shake 2008 
earthquake exercise.  The ground rules (namely restricting use of the Internet for 
the first part of the exercise) compromised use of ShakeMap. 
 
Once it was available it seemed like many persons involved made little or no use 
of ShakeMap.  The sense of this group is that this lack of use arises at least in 
part from lack of familiarity with ShakeMap.  One person commented that 
handing an EOC staff member a ShakeMap manual and telling them to read it is 
not a useful tactic.  To be useful to EOC personnel and responders in the field, 
ShakeMap has to be easy to use, and these people need adequate training in its 
use ( but not too much training, because if it requires too much training, we have 
failed in the first requirement).
     
Several people agreed with the statement that a clearly highlighted link to the 
“did you feel it” map from the ShakeMap page for any earthquake would be 
helpful for initial evaluation of geographic extent of an earthquake’s effects. 
C.B. Crouse speculated that emergency response personnel in Washington and 
Oregon might be able to learn more about ShakeMap by being directed toward 
California earthquake ShakeMaps and “playing” with them.  Eric Holdeman 2
thought that such people might be better motivated to learn about ShakeMap by 
studying ShakeMaps for PNW earthquakes.  To increase the “stock” of such 
earthquakes, he suggested that we might lower the ShakeMap threshold to 
magnitude 3.0. 
     
Multiple ShakeMap updates were a source of confusion during the Sound Shake 
exercise.   In a real earthquake, such updates will happen.  This confusion 
indicates the need for better communication between seismologists and EOC 
personnel and responders about ShakeMap and its use and limitations (see 
comments above about “keeping things simple”). 
      
Someone commented that being able to make ground motion information 
available to EOC’s for rapid import into their own GIS systems would be a good 
thing. 
 
Instrumentation of dams along the central Columbia River in Eastern 
Washington 
   
Craig Weaver required or is likely to require that a half-dozen dams along the Columbia have 
some level of seismic instrumentation installed on and/or near them.  Two 
instruments have just been installed on the Wells Dam by the USGS and PNSN. 
Presumably the dam operators will purchase the instruments themselves.  The 
question is how involved should the PNSN be in installing and maintaining these 
instruments, and what should the PNSN’s role be in collection and analysis of the 
data. 
 
This group did not arrive at definite answers to these questions. 
Concerns that were raised include: 
 
C.B. - a detailed characterization of a dam’s response to strong ground motion will 
require more that two or three sets of tri-axial accelerometers. 
     
Engineering expertise is needed to decide what instrumentation is appropriate for 
each dam. 
 
NetQuakes 
 
Craig Weaver gave a brief description of the “NetQuake” strong motion 
seismograph.  It is a relatively cheap (approximately ~$3K per unit) instrument 
that could be installed at any location that had DSL or cable broadband Internet 
service.  Paul Bodin said that a NetQuakes seismograph would automatically 
send triggered event data to a central data collection center (in this case the 
PNSN), ready for inclusion in an earthworm data processing stream. 3
C.B. noted that $3K per unit still seemed pretty expensive.  Someone 
commented that if funding was available to place a large enough order, the per 
unit cost might decrease. 
   
Craig said that the Department of Homeland Security has expressed some 
interest in funding a large deployment of these units in the region between 
Seattle and the Canada border, as a prelude to the 2010 Winter Olympic Games. 
Craig reported that some Southern California seismologists have hailed 
NetQuakes as the “next great revolution” in seismology and that such 
instruments are the best hope of achieving the necessary urban seismograph 
densities to fulfill the goals of the ANSS. 
 
 
Earthquake Early Warning (EEW) 
     
John Vildale led this discussion.  Some countries (notably Japan) have made 
significant progress toward the goal of EEW.  Steve Malone agreed that most of 
the technical and scientific problems have been resolved.   What is lacking is 
adequate funding to construct a truly adequate warning system including 
hardened telemetry and warning broadcast systems.  Also, the benefits of EEW 
implementation are not proven, but with some experience in other regions will 
become more clear. 
     
Social engineering issues include a robust way to get the early warning out and 
training the populace how to best respond to such warnings.  There are also 
questions about the cost-benefit ratio of such warnings.  These problems and 
questions still have not been answered. 
     
Joan Gomberg noted that at the recent Nation Earthquake Conference, 1/3 of 
attendees indicated that they thought EEW was a “good idea”.  Someone noted 
that this may have been the equivalent of voting for Mom and Apple Pie. 
It was noted that the SESAC report took a cautious view regarding EEW and 
although it supported further research on this topic, it should not be at the 
expense of other ANSS goals (i.e., it should not have top priority). 
 
Structural Monitoring  (led by John Vidale)
     
See the accompanying PDF/Power Point presentation for the bullets for this 
topic.  John reported that two tri-axial strong motion units will soon be temporarily 
installed on the Alaska Way viaduct. 
     
Overall the structural engineering community has not provided much guidance to 
the PNSN regarding ways to contribute to the advance of knowledge of seismic 
response of buildings, despite several offers to explore ways to monitor 
vulnerable structures such as the Tacoma Narrows Bridge and the Viaduct. Until 
this happens, the PNSN cannot do much more than it already has done, which 
so far is only some remedial Nisqually analysis and simple monitoring 
experiments in the UW Tower and on the viaduct. 
 
GPS data in monitoring 
     
See the PDF/Power Point presentation for bullets on this topic.  They were read 
with a few comments and we then moved on to the next topic. 
 
Aftershock probabilities 
 
Joan Gomberg reported that the major road block to completing an aftershock 
probability study for the Pacific Northwest was time and personnel. 
This problem is also probably more complicated than in California, because of 
the three distinct classes of earthquakes in the PNW:  subduction, shallow crustal 
and Benioff zone earthquakes. 
 
C.B. suggested studying other subduction zones as possible analogs to the 
Cascadia for the aftershock problem. 
     
The committee recommends that the completion of an aftershock probability 
study be placed at a higher priority. 
 
ETS (Episodic Tremor and Slip) studies 
     
John Vidale showed seismograms of Cascadia tremor induced by the passage of 
waves from the China earthquake.  Joan Gomberg expressed optimism that 
instrumentation deployed in the last few years and the concentration of research 
activity on ETS will lead to a much greater understanding of subduction zone 
processes. 
 
State of Oregon support for earthquake hazard studies 
     
Oregon DOGAMI (Department of Geology and Mineral Industries) obtained 
~$100K from the state to purchase 3 TA stations, which the PNSN will operate 
and maintain.  In the past ~2 years, DOGAMI has purchased three strong motion 
instruments to be added to the PNSN.  Two of those three strong motion sensors 
have been installed in Newport and Monmouth, Oregon.  The third is slated for 
installation somewhere in eastern Oregon, hopefully by the fall of 2008. 5
We noted ongoing operational fiscal support from the State of Oregon for the 
PNSN would be beneficial, and bring monitoring in that state more in line with the 
arrangements for monitoring in other states. 
 
Closing thoughts and summary of priority actions  
     
The coming year may see significant fiscal constraints on network operations and 
new initiatives.  The retirements of George Crawford and Ron Teissere and the 
current uncertain status of the Washington State Seismic Safety Commission 
presents challenges for continued progress on earthquake issues in state 
government. 
     
We briefly discussed membership of the Advisory Committee and no major 
changes were viewed as necessary. 
 
Action items: 
     
C.B. Crouse, Susan Chang, and Bill Perkins urge that high priority be given to 
the replacement of the failed deepest borehole seismometer at the Seattle 
School District headquarters in the Duwamish Valley. 
     
The committee also encourages increased priority be given to completion of a 
PNW aftershock probability study. 
 
List of Attendees: 
C.B. Crouse, Chair  URS Corporation 
T.J. McDonald  City of Seattle Emergency Management 
Dave Nelson   Washington State Emergency Management Division 
Susan Chang  City of Seattle 
Craig Weaver  USGS Seattle 
Bob Zimmerman  Boeing and CREW 
Gary Gordon   Boeing 
Bill Perkins   Shannon and Wilson 
Eric Holdeman  ICF International 
Tim Walsh   Washington DNR 
Recep (Ray) Cakir  Washington DNR 
Luke Meyers   Pierce County Emergency Management 
John Vidale   PNSN, ANSS Regional Co-ordinator 
Paul Bodin   PNSN 
Steve Malone  PNSN (emeritus) 
Bill Steele   PNSN 
Joan Gomberg  USGS Seattle 
Tom Yelin   USGS Seattle  
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