Dr. Lucy Jones Center
@dljcss.bsky.social
The Dr. Lucy Jones Center for Science & Society, founded by seismologist Dr. Lucy Jones, fosters the understanding & application of scientific information.
Reposted by Dr. Lucy Jones Center
Only the Rialto events are aftershocks to the July 31 M4.3. The Lytle Creek events are near the San Andreas but not necessarily on it. We often see small events around the San Andreas but some analyses suggest they are on small faults not the main surface that will move in the big quakes.
August 6, 2025 at 10:56 PM
Only the Rialto events are aftershocks to the July 31 M4.3. The Lytle Creek events are near the San Andreas but not necessarily on it. We often see small events around the San Andreas but some analyses suggest they are on small faults not the main surface that will move in the big quakes.
Reposted by Dr. Lucy Jones Center
In the last 24 hours, we have seen several M3s in 3 locations. The events near Ontario are at the western end of the Fontana trend. The Lytle Creek events are near the San Andreas & the Rialto events are where the Fontana trend intersects the San Andreas. Last week's M4.3 was at the Rialto location
August 6, 2025 at 10:56 PM
In the last 24 hours, we have seen several M3s in 3 locations. The events near Ontario are at the western end of the Fontana trend. The Lytle Creek events are near the San Andreas & the Rialto events are where the Fontana trend intersects the San Andreas. Last week's M4.3 was at the Rialto location
Reposted by Dr. Lucy Jones Center
The New York - Philadelphia - Wilmington urban corridor has felt small earthquakes roughly every 2-3 years. Moderately damaging earthquakes strike somewhere in the urban corridor roughly twice a century. So infrequent but not weird
M 3.0 - NE of Hasbrouck Heights, New Jersey
Did you feel it? Report it!
earthquake.usgs.gov/earthquakes/...
Did you feel it? Report it!
earthquake.usgs.gov/earthquakes/...
August 3, 2025 at 2:32 AM
The New York - Philadelphia - Wilmington urban corridor has felt small earthquakes roughly every 2-3 years. Moderately damaging earthquakes strike somewhere in the urban corridor roughly twice a century. So infrequent but not weird
Reposted by Dr. Lucy Jones Center
On the M4.3 on the Fontana trend
July 31, 2025 at 10:07 PM
On the M4.3 on the Fontana trend
A series of earthquakes, including a preliminary M4.3, shook the San Bernardino area Thursday morning, with shaking felt across SoCal. @drlucyjones.bsky.social explains what it means—watch the full discussion on NBC LA: www.nbclosangeles.com/news/earthqu...
Magnitude-4.3 earthquake in San Bernardino area shakes parts of Southern California
A preliminary magnitude-4.3 earthquake and smaller quakes in the San Bernardino area produced shaking Thursday morning that was felt over widespread parts of Southern California. The quake, reported a...
www.nbclosangeles.com
July 31, 2025 at 9:29 PM
A series of earthquakes, including a preliminary M4.3, shook the San Bernardino area Thursday morning, with shaking felt across SoCal. @drlucyjones.bsky.social explains what it means—watch the full discussion on NBC LA: www.nbclosangeles.com/news/earthqu...
Reposted by Dr. Lucy Jones Center
Looks like a small swarm in the Fontana trend. This M4.2 had a few foreshcoks including a M3.0. The Fontana trend is a NE-striking lineation of earthquakes under the sediments of the San Bernardino Vslley. We believe it is one of the left-lateral striking faults that are south of the San Gabriels.
#AutoEQ A magnitude 4.2 (MI) #earthquake has occurred 4 mi W of Muscoy, CA at 09:32 PDT Jul 31, 2025 [2025-07-31 16:32 UTC]. #SCSN has not yet confirmed this event. For more info visit http://earthquake.usgs.gov/earthquakes/eventpage/ci41249496#executive
July 31, 2025 at 4:41 PM
Looks like a small swarm in the Fontana trend. This M4.2 had a few foreshcoks including a M3.0. The Fontana trend is a NE-striking lineation of earthquakes under the sediments of the San Bernardino Vslley. We believe it is one of the left-lateral striking faults that are south of the San Gabriels.
Reposted by Dr. Lucy Jones Center
I’m seeing lots of questions about whether the rate of great earthquakes is changing or whether climate change affects earthquakes. The answer is no. The long term rate of these big events is about 1/decade. But the distribution is random. The last one was 2011 in Japan
July 30, 2025 at 3:19 PM
I’m seeing lots of questions about whether the rate of great earthquakes is changing or whether climate change affects earthquakes. The answer is no. The long term rate of these big events is about 1/decade. But the distribution is random. The last one was 2011 in Japan
Reposted by Dr. Lucy Jones Center
The 7/29/2025 M8.8 looks like a repeat of an earthquake in 1952
Another quick comparison of the 1952 #Kamchatka #earthquake from MacInnes et al. (2010) with today’s M8.8 event. The aftershock areas are similar, as well as one region of foreshocks. The updated USGS rupture model has a max slip of 10m versus 12m for 1952, with SW rupture direction. 🧪⚒️
July 30, 2025 at 3:19 PM
The 7/29/2025 M8.8 looks like a repeat of an earthquake in 1952
An 8.7M earthquake in Russia has prompted a tsunami watch along the entire #California coast. @drlucyjones.bsky.social takes a closer look at the initial temblor and what the watch means in this NBC LA interview: www.youtube.com/watch?v=Uw2E...
Tsunami watch issued for California coast. Dr. Lucy Jones explains what that means
YouTube video by NBCLA
www.youtube.com
July 30, 2025 at 2:54 AM
An 8.7M earthquake in Russia has prompted a tsunami watch along the entire #California coast. @drlucyjones.bsky.social takes a closer look at the initial temblor and what the watch means in this NBC LA interview: www.youtube.com/watch?v=Uw2E...
@drlucyjones.bsky.social joins KTLA5 to discuss the California coast #tsunami watch following the 8.7M quake in Russia. Watch the full interview: www.youtube.com/watch?v=NuKG...
California coast under tsunami watch after Russia earthquake
YouTube video by KTLA 5
www.youtube.com
July 30, 2025 at 2:40 AM
@drlucyjones.bsky.social joins KTLA5 to discuss the California coast #tsunami watch following the 8.7M quake in Russia. Watch the full interview: www.youtube.com/watch?v=NuKG...
Reposted by Dr. Lucy Jones Center
In addition to many M7+ earthquakes, this boundary has also hosted half a dozen M8+ earthquakes. Red circles mark the epicenter above the site where fault rupture began, and yellow shows the area on the megathrust fault that ruptured.
July 16, 2025 at 11:13 PM
In addition to many M7+ earthquakes, this boundary has also hosted half a dozen M8+ earthquakes. Red circles mark the epicenter above the site where fault rupture began, and yellow shows the area on the megathrust fault that ruptured.
Reposted by Dr. Lucy Jones Center
Even very small quakes can be felt if you are nearby (and a shallow quake is closer to people on the surface). But there is not much to be said about an M2.7 except that it happened
earthquake.usgs.gov/earthquakes/...
earthquake.usgs.gov/earthquakes/...
June 24, 2025 at 7:32 PM
Even very small quakes can be felt if you are nearby (and a shallow quake is closer to people on the surface). But there is not much to be said about an M2.7 except that it happened
earthquake.usgs.gov/earthquakes/...
earthquake.usgs.gov/earthquakes/...
Reposted by Dr. Lucy Jones Center
I once had a M2.7 directly under my house that felt so strong I went to work without waiting for a page (in pre-Internet days). It's a good reminder that how strong the shaking feels has much more to do with how close you are to the event. Duration of shaking is better for guessing magnitude.
June 24, 2025 at 7:38 PM
I once had a M2.7 directly under my house that felt so strong I went to work without waiting for a page (in pre-Internet days). It's a good reminder that how strong the shaking feels has much more to do with how close you are to the event. Duration of shaking is better for guessing magnitude.
Reposted by Dr. Lucy Jones Center
This study uses "overdue" to mean that time time since the last quake is longer than the average time between earthquakes. But that doesn't mean the next quake is more likely in the near future. The length of intervals between events is very variable even at one location.
Can you expand on what you mean?
June 8, 2025 at 4:33 AM
This study uses "overdue" to mean that time time since the last quake is longer than the average time between earthquakes. But that doesn't mean the next quake is more likely in the near future. The length of intervals between events is very variable even at one location.
Reposted by Dr. Lucy Jones Center
This does not mean the big earthquake is more likely. Whatever is making for long intervals is happening now.
Study says California is overdue for a major earthquake. Does that mean ‘the big one’ is coming?—About 45% of the faults analyzed for California are running behind schedule for a major earthquake, meaning… www.sfchronicle.com/science/arti... @jackjlee.bsky.social @sfchronicle.com
Study says California is overdue for a major earthquake. Does that mean ‘the big one’ is coming?
A new earthquake study reported that a large share of California faults have been running “late,” based on the expected time span between damaging temblors.
www.sfchronicle.com
June 7, 2025 at 6:13 PM
This does not mean the big earthquake is more likely. Whatever is making for long intervals is happening now.
A new study outlines the flooding risk from a magnitude 9 quake along the 700-mile Cascadia fault [email protected] explains that while we could still see damage for coastal areas, the fault line is offshore, so the heaviest shaking would be underwater. Watch her full interview on ABC7:
Could monster 9.0-magnitude earthquake sink part of CA's coastal communities?
Could a monster earthquake sink a portion of Northern California? A new study calculates the risk of where and how much land could sink, but experts say there's something else closer to home that we s...
abc7.com
May 20, 2025 at 11:26 PM
A new study outlines the flooding risk from a magnitude 9 quake along the 700-mile Cascadia fault [email protected] explains that while we could still see damage for coastal areas, the fault line is offshore, so the heaviest shaking would be underwater. Watch her full interview on ABC7:
Last week, @drlucyjones.bsky.social gave a lecture at the Newport Beach Public Library, providing insights on earthquake prediction, the importance of resilient structures, and why knowing your neighbors may matter most. Read more on the @latimes.com: www.latimes.com/socal/daily-...
O.C. residents pack Newport Beach hall to talk tectonics and tremors with seismologist Lucy Jones
About 100 people came out to learn from seismologist Dr. Lucy Jones at the Newport Beach Public Library's Friends Room Wednesday evening.
www.latimes.com
May 6, 2025 at 1:16 AM
Last week, @drlucyjones.bsky.social gave a lecture at the Newport Beach Public Library, providing insights on earthquake prediction, the importance of resilient structures, and why knowing your neighbors may matter most. Read more on the @latimes.com: www.latimes.com/socal/daily-...
Reposted by Dr. Lucy Jones Center
I've partnered with OcTech, Caltech's choral octet, to create Courage To Care: a concert & discussion to process climate angst in a time of historic fires. If you're in SoCal, come build community with us!
Sunday, April 27th, 7:30 PM
Dabney Lounge on the Caltech campus
Tickets: No tickets - free!
Sunday, April 27th, 7:30 PM
Dabney Lounge on the Caltech campus
Tickets: No tickets - free!
April 23, 2025 at 11:50 PM
I've partnered with OcTech, Caltech's choral octet, to create Courage To Care: a concert & discussion to process climate angst in a time of historic fires. If you're in SoCal, come build community with us!
Sunday, April 27th, 7:30 PM
Dabney Lounge on the Caltech campus
Tickets: No tickets - free!
Sunday, April 27th, 7:30 PM
Dabney Lounge on the Caltech campus
Tickets: No tickets - free!
@drlucyjones.bsky.social joined KCAL News today to discuss the recent 5.2-magnitude earthquake in #SanDiego County, noting a relatively large aftershock sequence. In the same interview, she also addressed the overall earthquake activity in #SoCal ▶️: www.youtube.com/watch?v=rFJ1...
Seismologist Dr. Lucy Jones discusses Monday’s 5.2-magnitude earthquake
YouTube video by KCAL News
www.youtube.com
April 15, 2025 at 11:35 PM
@drlucyjones.bsky.social joined KCAL News today to discuss the recent 5.2-magnitude earthquake in #SanDiego County, noting a relatively large aftershock sequence. In the same interview, she also addressed the overall earthquake activity in #SoCal ▶️: www.youtube.com/watch?v=rFJ1...
Reposted by Dr. Lucy Jones Center
Interesting to look at the detailed relocations of the aftershocks to the M5.2. It looks like they are not on the main strand of the Elsinore fault.
April 15, 2025 at 5:05 AM
Interesting to look at the detailed relocations of the aftershocks to the M5.2. It looks like they are not on the main strand of the Elsinore fault.
Reposted by Dr. Lucy Jones Center
Earthquake Early Warning requires estimating the magnitude from the first few seconds on just a few stations. It is always very rough but lets us get out something quickly. There is a lot of variation between locations. The final magnitude averages 100+ stations and is always more accurate
Out of curiosity, why was it first projected so high at 6.7 and then 6.0, only to be downgraded to 5.2? Felt it pretty strong here in Long Beach so we def thought it made more sense with the initial numbers stated.
April 14, 2025 at 8:50 PM
Earthquake Early Warning requires estimating the magnitude from the first few seconds on just a few stations. It is always very rough but lets us get out something quickly. There is a lot of variation between locations. The final magnitude averages 100+ stations and is always more accurate
Reposted by Dr. Lucy Jones Center
The USGS produces a nice quantification of the risk of aftershocks. 7% chance of another M5 and less than 1% chance of being followed by a M6.
April 14, 2025 at 6:11 PM
The USGS produces a nice quantification of the risk of aftershocks. 7% chance of another M5 and less than 1% chance of being followed by a M6.
Reposted by Dr. Lucy Jones Center
Today's M5.2 is the largest quake near the Elsinore fault since I came to California in 1983. But there were quite a few M4s along the way. A junior sibling to the San Andreas, the Elsinore is long enough to have given us some bigger events
April 14, 2025 at 6:11 PM
Today's M5.2 is the largest quake near the Elsinore fault since I came to California in 1983. But there were quite a few M4s along the way. A junior sibling to the San Andreas, the Elsinore is long enough to have given us some bigger events
A 7.7 quake struck Myanmar on Friday, killing over 2,000 people and shaking buildings as far as Bangkok. What caused this quake, and could it happen in the US? @drlucyjones.bsky.social joined ForbesWomen’s Maggie McGrath to answer these questions and more ▶️ www.youtube.com/watch?v=sc-v...
Why The Myanmar Earthquake Death Toll Could Be '10 Times To 100 Times' Higher Than Reported
YouTube video by Forbes Breaking News
www.youtube.com
April 2, 2025 at 9:50 PM
A 7.7 quake struck Myanmar on Friday, killing over 2,000 people and shaking buildings as far as Bangkok. What caused this quake, and could it happen in the US? @drlucyjones.bsky.social joined ForbesWomen’s Maggie McGrath to answer these questions and more ▶️ www.youtube.com/watch?v=sc-v...
Reposted by Dr. Lucy Jones Center
I was proud to be a federal scientist at the USGS for 33 years. "Earth science in the public service" meant I could focus on creating and explaining science for public officials and providing public education, not just educating students at one university. theconversation.com/us-earthquak...
US earthquake safety relies on federal employees’ expertise
The US experiences violent earthquakes, but the damage and death toll is much lower than in many countries because of the work of federal seismologists and engineers.
theconversation.com
April 2, 2025 at 2:35 AM
I was proud to be a federal scientist at the USGS for 33 years. "Earth science in the public service" meant I could focus on creating and explaining science for public officials and providing public education, not just educating students at one university. theconversation.com/us-earthquak...