Apr 14, 2025 - 5.2 quake North San Diego county

[T_R_Oglodyte]

preliminary USGS magnitude from the emergency alert on my phone

edits:
- hit in two pulses. First one lasted about three seconds. about one to two second later a second blast
- second blast was shorter but more powerful
- now https://earthquake.usgs.gov says it was a 5.2 quake located 4 km south of Julian, CA
- was one of the stronger quakes I have experienced in CA. Though significanly less powerful than the 1989 Loma Prieta quake that took out a section of the Bay Bridge, and collapsed part of the two-deck portion of the Nimitz Freeway in Oakland.
- thread title changed to indicate 5.2 quake instead of 6.2 as initially reported.

 

[melissy123]

In my office in downtown San Diego. Second floor. Seemed to go on forever. Strongest earthquake I’ve ever felt.

 

[GetawaysRus]

The Caltech site is showing more events than the USGS website:

Southern California Earthquake Data Center at Caltech

Initial quake now listed as magnitude 5.2, then lots of smaller aftershocks.

 

[easyrider]

preliminary USGS magnitude from the emergency alert on my phone

edits:
- hit in two pulses. First one lasted about three seconds. about one to two second later a second blast
- second blast was shorter but more powerful
- now https://earthquake.usgs.gov says it was a 5.2 quake located 4 km south of Julian, CA
- was one of the stronger quakes I have experienced in CA. Though significanly less powerful than the 1989 Loma Prieta quake that took out a section of the Bay Bridge, and collapsed part of the two-deck portion of the Nimitz Freeway in Oakland.

Is this the first feel-able earthquake for you ? We had a small one in Central Washington years ago and all it did was made the chandelier move a bit. Didn't feel a thing.

Bill

 

[WaikikiFirst]

significanly less powerful than the 1989 Loma Prieta quake

Maybe 6% as powerful???? Math majors welcome to apply. Reaction depends greatly on where you are at the time. In our 20+ yrs living in 2 spots in the CA coast, we had a 6.5 once, and almost nothing beside that. The 6.5 was 55 miles away. Not sure what it would measure at my house. But sitting in 1st floor of a house, I mostly was mesmerized by watching the walls vibrate in rhythm as the waves went up them. Who knew sheetrock is so pliable?
Otoh, the 1st quake I ever felt was about 4 am in a 5th fl hotel rm in Tokyo. On the 5th fl, I was damn close to running out the door and out to the street in my undies.

We had a tiny one (1.0 maybe???) 2 wks ago. It was BLIP and over.

 

[T_R_Oglodyte]

Is this the first feel-able earthquake for you ? We had a small one in Central Washington years ago and all it did was made the chandelier move a bit. Didn't feel a thing.

Bill

naw - I'm quake experienced from all of the time that I've spent on the west Coast. The first one I remember was ~ October 1974, when I was living in Redwood City, in the Bay Area. Since then, I remember some from all places we've lived on the west Coast.

The strongest one was the 1989 Loma Prieta quake (aka, the World Series quake). As mentioned above, when that one hit, I was stuck in traffic in Emeryville near the east end of the Bay Bridge, and about a mile from where the two-deck portion of the Nimitz Freeway. When that hit, I remember that I first estimated it as about a 5, based on intensity. But then it didn't stop; the waves just kept on coming. So, as it went on, I ratcheted up my estimates, to 5.5, then 6.0, and finally I figured it must be about a 6.5. I remember watching waves about 12" to18", peak to trough, moving across the ground surface.

The initial hammer on this one was about as strong as that (and some other 5s that I have experienced), but it didn't last.

What alarmed me most on this one was when the second tremor hit, and it was sharper than the first tremor. That was when I took precautions, thinking that this might be pre-shocks for something larger - I was next to the front door, so I headed outside.

 

[T_R_Oglodyte]

Maybe 6% as powerful???? Math majors welcome to apply. Reaction depends greatly on where you are at the time. In our 20+ yrs living in 2 spots in the CA coast, we had a 6.5 once, and almost nothing beside that. The 6.5 was almost 100 miles away. Not sure what it would measure at my house. But sitting in 1st floor of a house, I mostly was mesmerized by watching the walls vibrate in rhythm as the waves went up them.
Otoh, the 1st quake I ever felt was about 4 am in a 5th fl hotel rm in Tokyo. On the 5th fl, I was damn close to running out the door and out to the street in my undies.

The Richter scale is logarithmic. So a 5.2 quake is about one-tenth as strong as a 6.2 quake.

An important item for people to remember that power is not the same as intensity. Richter is a measure of the power released in a quake. Intensity is a measure of the ground shaking. They are related, but not directly related.

Earthquake waves a energy pulses moving through the ground. When the pulse reaches an area, the ground moves in response to the pulse. The amount of ground movement is related to the elasticity of the ground material. Think of elasticity as like a spring. If you have a strong spring and you put a weight on it, the spring needs to move only a little bit to support the spring. If you have a weak spring, the spring will move more and possibly deform because of the load.

Rock is strong and hard to deform. So when an earthquake wave moves through rock, the rock needs to move only a small amount in response to the wave. Loose materials, like much fill material on waterfront areas, is easily deformed and will even turn liquid under stress. So even a small quake can produce significant damage if the conditions are right.

I have made sure that every house I have ever owned has good contact with solid underlying rock.

 

[T_R_Oglodyte]

Just had a couple of small aftershocks, about 5 seconds apart.

 

[clifffaith]

I’d just had Oral B replacement brushes unlocked for me at CVS, and was walking toward the Mother’s Day cards when the quake alert went off on my phone. Thought it was an anti theft alarm, then I realized I was hearing it all around the store and the shaking started. Looked up to be sure ceiling panels weren’t coming down, then it was over. The Julian epicenter is about 90 miles from us. Not feeling any aftershocks here.

 

[T_R_Oglodyte]

When the 1989 Loma Prieta quake hit, I was working in an office in Walnut Creek, CA. The quake significantly disrupted some of our projects, and one of my teams was working on a Saturday to make up lost time. I was listening to a Stanford football game on the radio in my office, when I heard the announcers say that they were experiencing an aftershock. So, I got on the office intercom and told everyone that an aftershock was on the way and to prepare. It hit about 15 seconds later. Folks were amazed at how I knew that.

 

[emeryjre]

Any damage reports from the area
There are several major interchanges along HWY 15 that would not be far away
Escondido area not far away

 

[T_R_Oglodyte]

None at our house in Oceanside. DW in Encinitas said they are ok.

This was big enough that I would expect some V to VI level modified Mercalli intensity closer to the epicenter. We were at IV for the quake, III for the aftershocks I just noted.

 

[T_R_Oglodyte]

In my office in downtown San Diego. Second floor. Seemed to go on forever. Strongest earthquake I’ve ever felt.

When the 1989 Loma Prieta quake hit, we were working on a project that involved a major law firm with offices on the upper floors of the Transamerica building in SF. They were completely out of commission for several weeks.

After they returned to operation, I was talking with one of their paralegals. She said that there were filing cabinets launched two to three feet in the air during the quake they had to do dodge. Meanwhile, other office equipment items, such as fax machines, computers, and chairs, were also hazards. People started to huddle under desks for cover, but then the desks themselves became hazards.

 

[Janann]

preliminary USGS magnitude from the emergency alert on my phone

edits:
- hit in two pulses. First one lasted about three seconds. about one to two second later a second blast
- second blast was shorter but more powerful
- now https://earthquake.usgs.gov says it was a 5.2 quake located 4 km south of Julian, CA
- was one of the stronger quakes I have experienced in CA. Though significanly less powerful than the 1989 Loma Prieta quake that took out a section of the Bay Bridge, and collapsed part of the two-deck portion of the Nimitz Freeway in Oakland.

Please change the title of your post so that it says 5.2 instead of 6.2. There is a huge difference in those two numbers. I'm sure you don't want to alarm anyone unnecessarily.

 

[buzglyd]

My whole family in North county felt it. I’ve been in an airplane since 8:30 this morning and didn’t feel a thing. ;-). I told them we’ve had three hours of turbulence so I know how they feel.

 

[T_R_Oglodyte]

My whole family in North county felt it. I’ve been in an airplane since 8:30 this morning and didn’t feel a thing. ;-). I told them we’ve had three hours of turbulence so I know how they feel.

Mentioning earthquakes in the air ...

I was in the air from Tulsa to O'Hare to make a connection to SeaTac when the 6.8 Nisqually quake hit. I arrived at my connecting gate in O'Hare, to see everyone in the boarding gate starting at the TV monitors. Where CNN was on screen with live coverage of an earthquake in Seattle. About five minutes in, I saw pictures of damage in Pioneer Square, with my office building in the background.

 

[PcflEZFlng]

Any damage reports from the area
There are several major interchanges along HWY 15 that would not be far away
Escondido area not far away

No damage at home here in Escondido. My wife felt it at home and said it was very strong. I didn't feel it because I was driving at the time. I was about a mile from home when the alert came up on my phone.

 

[davidvel]

Any damage reports from the area
There are several major interchanges along HWY 15 that would not be far away
Escondido area not far away

Only reports were on the news of some bottles knocked off shelves at a store near the epicenter, and some rocks tumbled down onto Hwy 76.

 

[SmithOp]

I was preparing taxes in a room full of people, in Seal Beach, Orange County. All our cell phones went off but all I felt was a couple of short rocking motions of my chair.

 

[buzglyd]

I was preparing taxes in a room full of people, in Seal Beach, Orange County. All our cell phones went off but all I felt was a couple of short rocking motions of my chair.

And that probably was because Sweet Home Alabama was on the Muzak.

 

[emeryjre]

Only reports were on the news of some bottles knocked off shelves at a store near the epicenter, and some rocks tumbled down onto Hwy 76.

Southern California was extremely lucky
Thankfully

 

[davidvel]

Southern California was extremely lucky
Thankfully

Yes, fairly moderate strength in a very rural area. Not much to collapse out there.

Unfortunately, the southern segment of the San Andreas Fault is considered overdue for a major earthquake. Historically, the southern portion of the fault has experienced large earthquakes roughly every 150-200 years, but it's been about 300 years since the last major event. This extended quiet period has led to the accumulation of stress on the fault, making it more likely to release energy in a large earthquake.

 

[T_R_Oglodyte]

Yes, fairly moderate strength in a very rural area. Not much to collapse out there.

Unfortunately, the southern segment of the San Andreas Fault is considered overdue for a major earthquake. Historically, the southern portion of the fault has experienced large earthquakes roughly every 150-200 years, but it's been about 300 years since the last major event. This extended quiet period has led to the accumulation of stress on the fault, making it more likely to release energy in a large earthquake.

San Diego County is part of the Peninsular ranges, a different geologic segment than the San Andreas. (Actually, the San Andreas forms part of the north boundary of the Peninsular ranges. My take is that while the Peninsular Ranges are certainly quite active, they don't have quite the same degree of hazard as the LA Basin and other areas along the San Andreas fault and it's primary branches.

Extending the thought, the biggest earthquake hazard risk in western North America is the Juan de Fuca subduction zone, extending from Northern California to Alaska. That is capable of generating much more powerful quakes than the San Andreas, and the area off the Oregon and Washington coasts similarly has not moved for several hundred years.

 

[davidvel]

San Diego County is part of the Peninsular ranges, a different geologic segment than the San Andreas. (Actually, the San Andreas forms part of the north boundary of the Peninsular ranges. My take is that while the Peninsular Ranges are certainly quite active, they don't have quite the same degree of hazard as the LA Basin and other areas along the San Andreas fault and it's primary branches.

Extending the thought, the biggest earthquake hazard risk in western North America is the Juan de Fuca subduction zone, extending from Northern California to Alaska. That is capable of generating much more powerful quakes than the San Andreas, and the area off the Oregon and Washington coasts similarly has not moved for several hundred years.

I didn't mean that the So. San Andreas would directly affect S.D. We have few if any major faults west of the Salton Sea area, and none expected to cause major damage in S.D. L.A. is at major risk for a doozy.

 

[MULTIZ321]

https://www.gannett-cdn.com/authoring/authoring-images/2025/04/14/USAT/83090451007-clean.jpg?crop=1080,1079,x288,y0

Richard