The San Simeon and Parkfield Earthquakes What the CISN did well (and could have been done better)

M3 quake ≠ M6+ quake Big quakes –Have extended source regions –Are infrequent –Exercise software in unexpected ways –Shine spotlights on systems deficiencies –Overwhelm humans unaccustomed to response pressures and demand for information –Rarely happen when convenient

San Simeon Mw6.5 Earthquake Quake occurred December 22, 2003 at 11:15:56 AM (PST) –Monday –Staff gone for vacation Instrumentation was (and still is) sparse Instrumentation was (and still is) analog Quake occurred on edge of NC/SC networks

12/22/ :15:56 00:00:00Rupture initiates

12/22/ :16:2000:00:24 ? Quick Look Hypocenter

12/22/ :20:2500:04:29Final hypocenter & Md 5.6

12/22/ :20:5800:05:02ML 6.4

12/22/ :22:4000:06:44Mechanism & Mw 6.5

12/22/ :24:1300:08:171st ShakeMap - ML 6.4

12/22/ :38:2800:22:32ShakeMap update - Mw 6.5

San Simeon “Human” Time-line TimeElapsed (GMT)hr:mn:sc 19:32:0000:16:04Seismologist review and aftershock probabilities 20:00:0000:44:04OES conference call with CISN scientists 20:16:0001:00:04First HAZUS runs completed 20:30:0001:14:04Release of Internet Quick Report 21:54:0002:38:04Seismologist review of finite source

12/22/ :30:0001:14:041st Internet Quick Report

02:38:04

12/22/ :14:0002:58:04ShakeMap update

12/22/ :33:0004:17:04ShakeMap update - line source

12/23/ :34:0007:18:04ShakeMap update - Templeton data

12/24/ :28:0029:12:04ShakeMap update - Cambria data

12/23/ :34:0022:18:04Special Earthquake Report

J. Fenton

So far, so good…. Here’s what could have gone better 1.Technical issues –Competing EqintheNews pages on USGS servers in Golden, CO and Menlo Park, CA (fixed) –No ability to update aftershock probabilities (now can be done manually) –Clients inundated with automated /pager (potentially solvable) –Akamai/Reston firewall problems blocked recenteqs access (fixed) –CIT ShakeMap data exchange broken (fixed) –Dedicated com links from Parkfield broke (fixed)

2.Human Response –Inconsistent statements on mapped fault and name of quake on Day 1 –No communications with ShakeMap users about ShakeMap updates –Failure to exercise existing response procedures –SC "duty seismologist" for ShakeMap unknown in NC –~2 days to establish an internal scientific distribution list and ftp site –No 7 X 24 contact for USGS networking/security staff. Even after contact, fix took almost 2 weeks.

Limited station coverage and strong motion data in region compromised ShakeMap quality and science Distribution of ShakeMap stations = RT = Non-RT 3. Data Quality

Prototype operational –better locations –detected more earthquakes 4. Statewide pick exchange and association

Parkfield Overview Quake occurred Tuesday, September 28, 2004 at 11:15:56 AM (PST) –Key personnel in St. Louis for National Earthquake Conference Quake occurred within densely instrumented portion of NC network –SM data mostly non-RT

Parkfield time-line Earthquake Information UTC TimeElapsed time hr:mn:sc Origin Time (OT) 09/28 17:15:2400:00:00 Quick Look hypocenter 09/28 17:15:5500:00:31 Final hypocenter & M d /28 17:19:5700:04:33 First Motion mechanism 09/28 17:20:1000:04:46 Local Magnitude M L /28 17:20:3000:05:06 1st ShakeMap completed 09/28 17:21:1600:05:52 Moment Tensor Solution M w 5.909/28 17:22:2300:06:59 2nd ShakeMap completed 09/28 17:28:0800:07:44 MS relocated by duty seismologist09/28 17:46:--00:31:-- Analyst review of moment tensor 09/28 17:47:--00:32:-- ShakeMap update due to relocation09/28 17:53:--00:38:-- Finite fault line source09/20 17:54:--00:39 Probability statement released for M L 5.909/28 18:00:--00:45:-- ShakeMap update with manual finite fault09/28 18:20:--01:05:-- Update to Mw6.0 & probability revision 09/28 18:23:--01:08:-- ShakeMap update with 6 stations09/28 21:18:--04:03:-- Earthquake Report at cisn.org 09/28 21:45:--04:30:-- 1st Internet Quick Report at cisn-edc.org 09/29 01:56:--08:41:-- ShakeMap update with 1 added station09/29 05:20:--12:05:-- Four additional IQR releases09/29-10/27 ShakeMap updates with CGS/NSMP data10/08 --:--:--10 days Automatic OES/CISN exchange

Locations almost perfect

100 km distance weighting 28 SEP 2004, 17:15 SEQUENCE NO. 1, ID NO ADJUSTMENTS (KM) I ORIGIN LAT N LON W Z NWR RMS DT DLAT DLON DZ RR NF MOD PGH PGH FREE DEPTH PGH BEGIN DISTANCE WEIGHTING BEGIN RESIDUAL WEIGHTING DEPTH ADJUSTMENT DAMPED PGH RMS INCREASE - MOVE HYPO 0.60 BACK PGH RMS INCREASE - MOVE HYPO 0.60 BACK PGH RMS INCREASE - MOVE HYPO 0.60 BACK PGH RMS INCREASE - MOVE HYPO 0.60 BACK PGH RMS INCREASE - MOVE HYPO 0.60 BACK PGH RMS INCREASE - MOVE HYPO 0.60 BACK PGH DEPTH ADJUSTMENT DAMPED PGH RMS INCREASE - MOVE HYPO 0.60 BACK

24 hours

10 days later

Web traffic Request or hit count peak of 630,000/min (10,500/sec) 300,000 different IP addresses on day 1 100GB transferred on day 1 (typically 8 GB)

Did You Feel It? 7,000 questionnaires submitted for this event in the first hour 14,174 total

4:30

8:41

Parkfield Issues Technical –Mainshock and two M5 aftershocks initially mislocated (fixed) –Strong motion data exchange from CGS hung (fixed?) –Reviewed Mw update had to be forced (not fixed) –Incorrect aftershock M5 magnitudes (fixed?) Human –Duty seismologist failed to follow procedures and aftershock message was delayed –Staff overload because key individuals in St Louis Data –Most strong-motion data non-RT and recorded on film

Summary CISN delivered rapid and reliable information for San Simeon and Parkfield quakes. Technical “glitches” were addressable Human “glitches” challenging Limited instrumentation and data quality remain a significant impediment