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Caltech Seismological Laboratory @caltechseismo.bsky.social · 3d

Weekly Earthquake Stats: 28 Sep 2025 - 04 Oct 2025. There were 206 events this week ranging from M 0.17 to 3.18. Check out our weekly playback map and visit www.scsn.org for detailed information. #earthquakes #seismology #SCSN #weeklystats @CaltechSeismo

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 8d

Congratulations to longtime USGS field tech Scott Lydeen on his retirement! Scott spent decades maintaining & upgrading SCSN stations across SoCal, always innovating and working hand-in-hand with Caltech staff. His legacy lives on, not least at the seismic site named after him. Thank you, Scott!

Center Scott Lydeen, Retired SCSN engineers and scientists

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 10d

Weekly Earthquake Stats: 21 Sep 2025 - 27 Sep 2025. There were 304 events this week ranging from M -0.27 to 3.28. Check out our weekly playback map and visit www.scsn.org for detailed information. #earthquakes #seismology #SCSN #weeklystats @CaltechSeismo

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 12d

Today’s #FieldPhotoFriday takes us to the desert near the Brawley Seismic Zone, where one of out our seismic stations recently received a new datalogger. Fieldwork in these conditions can be tough, but thanks to the combined efforts of Caltech Seismo Lab and USGS staff, the network stays strong!

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 16d

Mid-sized quakes like this are a reminder to:
Check your emergency kit, Know your local resources, Refresh your preparedness plan, and remember preparedness today helps when a bigger quake happens!

Caltech Seismological Laboratory @caltechseismo.bsky.social · 16d

This morning's M4.3 quake near Berkeley, CA sent clear waves across the SCSN. Watch how the waves arrived, even at over 300 miles away to our closest stations!
buff.ly/Q4LwDvz

And don't forget that if you felt shaking, report it here in "DYFI": buff.ly/8VxJvlQ

M4.3 Berkeley, Ca 2025-09-22 2:56am PST Regional Event

NOTE: Earthquake data may be preliminary and subject to change.

youtu.be

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 17d

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 17d

Weekly Earthquake Stats: 14 Sep 2025 - 20 Sep 2025. There were 316 events this week ranging from M -0.24 to 3.58. Check out our weekly playback map and visit www.scsn.org for detailed information. #earthquakes #seismology #SCSN #weeklystats @CaltechSeismo

SCSN | Southern California Seismic Network

For data archive access visit SCEDC

www.scsn.org

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 19d

Speaking of earthquake drills, next month is the international ShakeOut drill! Held at 10:16 am (local time) on 10/16, it's a great opportunity to practice protective actions like Drop, Cover, and Hold On. To find out more and register, check out: buff.ly/SFPgSS8

Great ShakeOut Earthquake Drills

Great ShakeOut Earthquake Drills help people in homes, schools, and organizations worldwide improve preparedness and practice how to be safe during earthquakes. Register to participate in your state…

www.shakeout.org

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 19d

Every Sept 19, earthquake preparedness drills are run commemorate this quake and to prepare for future ones. buff.ly/2FL98JM

El Gran ShakeOut de Otros estados o países

Los simulacros ShakeOut ayudan a familias, escuelas y organizaciones alrededor del mundo a prepararse y practicar cómo hacerse seguro durante un terremoto. Inscríbase a www.ShakeOut.org/espanol para…

buff.ly

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 19d

#EQHistory: Today marks the 40th anniversary of the 1985 M8.0 Michoacan, Mexico, earthquake. Causing widespread damage and loss of 9500+ lives, many in the greater Mexico City area, this event was the impetus for creating Mexico's Earthquake Early Warning system, the first world's public EEW system.

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 19d

#FieldPhotoFriday Not all of our seismic stations are out in the desert or up in the mountains, a vast amount are actually in or on state, federal, or private properties like schools, fire stations, museums, and more! Like this station near New Cuyama at a school, recently visited and updated!

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 20d

SCSN manager Allen Husker has had a busy week! In addition to the last post's activities, he's been in meetings with Rep. Suzanne Bonamici, District 1, Oregon about appropriation, and a trip to NASA Goddard Space Flight Center to see the LEMS (buff.ly/JD2CQ0u) that are set to go to the moon!

Rep. Suzanne Bonamici from District 1 from Oregon speaking during appropriations meeting

Allen holding a model of the LEMS during Nasa Goddard Space Flight Center Visit.

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 21d

In SoCal we are particularly focused on high-risk offshore faults capable of M7+ quakes and the potential of DAS to improve our network coverage.

Improving and extending this life-saving tech requires continued federal support, which is why they're in D.C., to strengthen our nation's EQ resiliency.

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 21d

They're meeting with congressional representatives and staff to highlight the importance of EQ early warning systems, especially as we look to expand ShakeAlert into offshore regions and other states like Nevada.

#Preparedness #SCSN #DAS #Seismology

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 21d

This week SCSN manager Allen Husker is in Washington DC along with a delegation from West Coast universities involved in #ShakeAlert.

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 24d

Weekly Earthquake Stats: 07 Sep 2025 - 13 Sep 2025. There were 404 events this week ranging from M -0.21 to 3.69. Check out our weekly playback map and visit www.scsn.org for detailed information. #earthquakes #seismology #SCSN #weeklystats @CaltechSeismo

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 26d

#FieldPhotoFriday Recently the crew got to go somewhere different than the desert! Up in the mountains of Santa Barbara one of our stations needed new batteries and a new datalogger. Excellent work as usual keeping our massive network reliable and ready for any shaking!

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Caltech Seismological Laboratory @caltechseismo.bsky.social · 29d

This year one of our EQ Fellows groups took their research to SCEC! Abellaine, Parisa, Flora, and Jacob presented their poster "On the Origin of Seismic Signals from Concerts and its Potential Use to Monitor Stadium Health" and gained valuable experience! EQ Fellows Program: buff.ly/KrHJG5P

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Caltech Seismological Laboratory @caltechseismo.bsky.social · Sep 8

SCEC 2025: Gabrielle Tepp (SCSN) presents on “Evaluation of DAS Phase Pick Quality and Performance.” Her work explores how DAS data could improve real-time earthquake monitoring across Southern California.
buff.ly/hpHJxP4

Plots showing how well events were detected by analysts and a machine-learning picker based on event magnitude and distance from the fiber cable

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Caltech Seismological Laboratory @caltechseismo.bsky.social · Sep 8

SCEC 2025: Prof. Tom Heaton (Caltech Seismological Laboratory) presents on “Slip Pulses and PSHA.” His work explores the chaotic physics of slip pulses and what they mean for earthquake hazard analysis and building safety.

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Caltech Seismological Laboratory @caltechseismo.bsky.social · Sep 8

SCEC 2025: Jessie Saunders (SCSN) is evaluating earthquake early warning performance using responses to the “Did You Feel It?” survey. Their work helps measure how the U.S. ShakeAlert system is performing in real-world events.
buff.ly/Hcf3zip

Evaluating earthquake early warning performance using "Did You Feel It?" | Statewide California Earthquake Center

Central Functions

central.scec.org

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Caltech Seismological Laboratory @caltechseismo.bsky.social · Sep 8

The SCEC Annual Meeting kicks off this week in Palm Springs! Members of the SCSN and Caltech Seismo Lab are attending, presenting, and collaborating with colleagues across the earthquake science community.
buff.ly/1FJngtZ

2025 SCEC Annual Meeting | Statewide California Earthquake Center

Central Functions

central.scec.org

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Caltech Seismological Laboratory @caltechseismo.bsky.social · Sep 7

Weekly Earthquake Stats: 31 Aug 2025 - 06 Sep 2025. There were 365 events this week ranging from M -0.45 to 2.97. Check out our weekly playback map and visit www.scsn.org for detailed information. #earthquakes #seismology #SCSN #weeklystats @CaltechSeismo

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Caltech Seismological Laboratory @caltechseismo.bsky.social · Sep 7

M3.5 10km N of #LaVerne, CA, #SouthernCalifornia #Earthquake confirmed valid. Updated analysis coming soon @ buff.ly/YnlVPfk And make sure if you felt it that you fill out the DYFI page on the USGS! buff.ly/wXQMPcu

www.scsn.org

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