Easter Earthquake In California

[zoobyshoe]

I was down at the cafe where I hang out this afternoon while a clever person of my acquaintance was at work fixing my laptop, when the table started doing a rock and roll dance. I thought at first he was pushing on it and he thought I was doing it. Suddenly we both realized it was an earthquake. Every one else in the place realized the same thing about that time and everyone stood up. Thinking at first I should go outside, I decided against it: there was more stuff that might fall on you out there than inside. The floor was shaking as if the building were strapped on a big truck barreling down the highway. The chandeliers were swaying, and when I looked outside I saw all the streetlights were swinging back and forth as well. I've been in about 5 or 6 quakes in the time I've lived here but this was the first mid-afternoon quake I remember, and the first time I have been out in public to see a lot of other people's reaction when it happened.

6.9 magnitude 2010 Easter earthquake strikes California



Just south of the U.S. - Mexico border an earthquake of a 6.9 magnitude struck in Baja, California on Easter Sunday, 04/04/10. According to seismologists, the quake was felt as far north as Santa Barbara. The earthquake occurred at 3:40 p.m. according to the U.S. Geological Survey. For those dining on their Easter meal or otherwise enjoying a relaxing, this was a bit of a rude shock that lasted somewhere in the area of 40 seconds. The earthquake comes on the heels of a week marked by a series of smaller 3.0 magnitude earthquakes, and aftershocks are expected.



While no major damage has been reported at this point, high-rises in the San Diego and Los Angeles area swayed, Riverside and Coachella Valley reported strong shaking, and the tremors were strong enough to be felt in Arizona as well. Jacqueline Land of Phoenix, Arizona, stated “That can’t be an earthquake. I’m in Arizona.” The Yuma police department reported the quake was quite strong there, but that no damage has been reported or observed.

http://www.helium.com/items/1794329-69-magnitude-2010-easter-earthquake-strikes-california

 

[Ben Niehoff]

hmm...at that time of day we were at the Arboretum in Arcadia. I didn't feel any earthquake whatsoever. Weird.

 

[Math Is Hard]

I heard it was upgraded to a 7.2. It woke me up from my nap and gave me some awful sea sickness. Things were still swinging a minute or two after the main shock passed.

 

[GRB 080319B]

At first I thought it was someone driving by with the ghetto-blasting bass, but the banging got progressively louder and things started to shake strongly. It created a cool tsunami-like effect in the pool that lasted about a minute after the shaking stopped.

 

[Ben Niehoff]

Are you people kidding? I seriously didn't feel a thing. If it occurred at 3:40 in Baja, then when should it have reached LA?

 

[hypatia]

Glad everyone is ok.

 

[Max Faust]

BBC reports it at 7.2.

 

[Zantra]

Felt it a bit in Orange County. Got the overhead fan swinging and the bookcase trembling, but not as bad as the quake last year. That one was much worse. But called my friend up in LA, and he didn't even feel it.

 

[zoobyshoe]

I saw a picture of a store in Mexico close to the epicenter: all the goods had been shaken off the shelves.

It wasn't that bad here. Some of the pictures on the wall were crooked after the quake, but nothing came down.

 

[GeorginaS]

That sounds like quite the experience to live through. And certainly one of those where, in the instant, you're not sure what to do. Go outside, stay indoors, find a doorframe, crawl under a table, order some booze. Could go any direction really.

I'm glad to hear folks around here are okay, though. That had to be rather alarming.

 

[zoobyshoe]

That sounds like quite the experience to live through. And certainly one of those where, in the instant, you're not sure what to do. Go outside, stay indoors, find a doorframe, crawl under a table, order some booze. Could go any direction really.

I'm glad to hear folks around here are okay, though. That had to be rather alarming.

Every time I've been in a quake it's the same indecision. You're always wondering: "Is the shaking going to get worse, or is this it?" Then you wonder, "How long is this going to last?" There's no telling what might be a safe position till you see what falls first. Most people in the cafe stood up instinctively. I think that was just to be ready to run away from whatever might fall.

 

[Evo]

Glad to hear everyone is ok. Don't know what I'd do in that situation.

 

[turbo]

Glad to hear everyone is ok. Don't know what I'd do in that situation.

You might want to figure it out, Evo. You're not all that far from the New Madrid fault, and that sucker is going to cut loose again someday.

 

[lisab]

Every time I've been in a quake it's the same indecision. You're always wondering: "Is the shaking going to get worse, or is this it?" Then you wonder, "How long is this going to last?" There's no telling what might be a safe position till you see what falls first. Most people in the cafe stood up instinctively. I think that was just to be ready to run away from whatever might fall.

Your instinct to not run outside was excellent. Last time we had a good one here in the Seattle area, there were injuries caused by building facades falling off onto the sidewalks below (from buildings built long before modern building codes). Running outside also exposes you to the hazard of falling glass, as the windows from higher stories break.

The credible sources I've read about "what to do" during the shaking: get under something sturdy, and hang on.

The advice used to be: get into a doorway. That's good advice if the door was built with a header; not all are, and there's no way to tell by looking how it was constructed. So that's no longer advised.

 

[Borek]

It didn't hit the news here, so even if it was quite strong, it wasn't devastating. 7.0-7.9 is considered a major one

Glad to hear only good news from PFers so far.

I don't want to even think about Evo in an earthquake. Not even 3.0.

Edit: actually, I think you should be glad it happened. Large amount of the energy was dispersed without disastrous effects.

 

[Astronuc]

Are you people kidding? I seriously didn't feel a thing. If it occurred at 3:40 in Baja, then when should it have reached LA?

Surface waves. What one feels depends on the frequency of the wave, the stiffness of the ground, the stiffness of the building and its natural frequency, and distance, among various factors.

It will also have to do with the geology and local interference.

There have been more than 500 quakes in and around S. Cal and Baja California, Mx, including some pretty good aftershocks.

http://earthquake.usgs.gov/earthquakes/recenteqsus/Quakes/ci14607652.php

 

[Math Is Hard]

Are you people kidding? I seriously didn't feel a thing. If it occurred at 3:40 in Baja, then when should it have reached LA?

I'm not kidding. We were rocking and rolling in the Marina. Maybe you were on the road? I usually don't feel them when I am driving.

I've heard a few people say water was sloshing out of their swimming pools. That must have been freaky.

 

[zoobyshoe]

Your instinct to not run outside was excellent. Last time we had a good one here in the Seattle area, there were injuries caused by building facades falling off onto the sidewalks below (from buildings built long before modern building codes). Running outside also exposes you to the hazard of falling glass, as the windows from higher stories break.

The credible sources I've read about "what to do" during the shaking: get under something sturdy, and hang on.

The advice used to be: get into a doorway. That's good advice if the door was built with a header; not all are, and there's no way to tell by looking how it was constructed. So that's no longer advised.

Yes, after I thought about going outside it occurred to me that the cafe and a few other businesses around had those Spanish roof tiles which might be shaken off and bean someone. On top of that, outdoors is where you'd have power lines coming down if it got that bad. The traffic lights which stick out from the main poles on stalks were wobbling back and forth pretty energetically. Inside it seemed the worst you might get is falling pieces of gypsum board.

 

[Evo]

Yes, after I thought about going outside it occurred to me that the cafe and a few other businesses around had those Spanish roof tiles which might be shaken off and bean someone. On top of that, outdoors is where you'd have power lines coming down if it got that bad. The traffic lights which stick out from the main poles on stalks were wobbling back and forth pretty energetically. Inside it seemed the worst you might get is falling pieces of gypsum board.

I've dealt with hurricanes, no problem, you have days even weeks to prepare and get out if necessary, tornadoes, much scarier, they can hit anywhere anytime and at night you can't even see them, you just hear the sirens so know it's close.

But when the Earth beneath you is shaking and any decision you make could be your last, yeah, that's got to be the worst.

 

[zoobyshoe]

I've dealt with hurricanes, no problem, you have days even weeks to prepare and get out if necessary, tornadoes, much scarier, they can hit anywhere anytime and at night you can't even see them, you just hear the sirens so know it's close.

But when the Earth beneath you is shaking and any decision you make could be your last, yeah, that's got to be the worst.

It's surreal to realize the whole Earth around you as far as you can see has massive waves running through it, large and powerful enough to shake the building you're in.

 

[TheStatutoryApe]

I felt it in Long Beach. I have been dealing with them since I was a kid so they are not really all that freaky to me. I have nothing dangerous to worry about in my apartment. I just looked around to make sure there was nothing that was going to fall and then went back to what I was doing. Had it gotten worse I may have moved away from the window.
The same thing happened to me as it did MIH. I was still getting over being sick (so a bit disoriented already) and the quake settled into a gentle roll for the last several seconds. At some point I realized that I was the one swaying and the ground had stopped moving.

Ben: Perhaps you were a ways away from a fault line?

 

[Ivan Seeking]

Checkout the dust cloud generated in the desert hills of Mexicali [presumably].
http://www.ireport.com/docs/DOC-428979?hpt=C2

 

[rewebster]

But when the Earth beneath you is shaking and any decision you make could be your last, yeah, that's got to be the worst.

well, I wonder how much of all of this (or any) has to do with global warming (crust expanding?).

And, it also seems that we're going through almost a cascading effect since the Haiti earthquake--almost as if it 'loosened' things up to allow the Chile and Mexico quakes---

where next?

 

[TheStatutoryApe]

Checkout the dust cloud generated in the desert hills of Mexicali [presumably].
http://www.ireport.com/docs/DOC-428979?hpt=C2

It started out with a pretty good shock here. I don't doubt that closer to the epicenter it could have stirred up some loose dry dust.

 

[TheStatutoryApe]

well, I wonder how much of all of this (or any) has to do with global warming (crust expanding?).

And, it also seems that we're going through almost a cascading effect since the Haiti earthquake--almost as if it 'loosened' things up to allow the Chile and Mexico quakes---

where next?

I was wondering if anyone might bring up global warming. I'm pretty sure that "earthquake weather" is a myth.

 

[rewebster]

I was wondering if anyone might bring up global warming. I'm pretty sure that "earthquake weather" is a myth.

its probably more likely than a 'gravity waves' myth...

 

[Ivan Seeking]

I was wondering if anyone might bring up global warming. I'm pretty sure that "earthquake weather" is a myth.

There has been some discussion that the release of radon gas, which is known to occur before some quakes, may account for some of these reports.

Absolute fact: The night before the San Fernando Quake, in 1971, while we were sitting and eating dinner, my dad looked out the window and declared that "it looks like earthquake weather". I don't recall him ever saying that before or since. I can still remember seeing a strange, slighty green hue to the color of the sky, just before dusk.

Late edit: I should probably add that we lived approximately 30 miles SSE of the epicenter, but we were looking west at the sunset when we noticed the sky.

 

[Frame Dragger]

What I find amusing is that the same people who take this in stride, might be the same people who think strangers always kidnap children, and terrorists are around every corner! People really tend to be... to... well they suck at risk assessment.

 

[Ivan Seeking]

What I find amusing is that the same people who take this in stride, might be the same people who think strangers always kidnap children, and terrorists are around every corner! People really tend to be... to... well they suck at risk assessment.

When a quake hits, when one is used to this, one generally knows almost instantly how serious it will be locally.

Lima, Peru, is an intersting place. They have noticable quakes almost every day. The locals say that the time to worry is when the quakes stop for a period of time; a big one is sure to follow.

 

[DaveC426913]

It created a cool tsunami-like effect in the pool that lasted about a minute after the shaking stopped.

I find this interesting. If the ground simply shook, one might expect some choppy waves but, ultimately, no displacement.

You describe a tsumani-like effect, which I'm going to go out on a limb and assume means a large sloshing back and forth.

It seems to me, this is a strong indication of, not just lateral oscillation (where the net movement is zero), but of lateral displacement (where the net movement is significant).

In the Chile earthquake last month, one of the tdibits that was reported was that the city of Concepcion and its surrounding countryside is now 10 feet to the left of where it was.
http://researchnews.osu.edu/archive/chilequakemap.htm

Heh. Anyone got a high-end GPS? I wonder if your house is still sitting where it was before the quake...

 

[Frame Dragger]

I find this interesting. If the ground simply shook, one might expect some choppy waves but, ultimately, no displacement.

You describe a tsumani-like effect, which I'm going to go out on a limb and assume means a large sloshing back and forth.

It seems to me, this is a strong indication of, not just lateral oscillation (where the net movement is zero), but of lateral displacement (where the net movement is significant).

In the Chile earthquake last month, one of the tdibits that was reported was that the city of Concepcion and its surrounding countryside is now 10 feet to the left of where it was.
http://researchnews.osu.edu/archive/chilequakemap.htm

Heh. Anyone got a high-end GPS? I wonder if your house is still sitting where it was before the quake...

Well, this is a Strike-Slip fault, so the displacement shouldn't be too significant. I suspecpt the "pool" effect had more to do with the depth of the quake.

 

[rewebster]

Heh. Anyone got a high-end GPS? I wonder if your house is still sitting where it was before the quake...

no...

my house moved, and...

is still moving...

at about 100,000 mph

 

[DaveC426913]

no...

my house moved, and...

is still moving...

at about 100,000 mph

Relative to the geosat coordinates?? You better go catch it!

 

[Frame Dragger]

Relative to the geosat coordinates?? You better go catch it!

Am I the only one who immidiately thought of "Is your refrigerator running?..."

Hey... and wouldn't a "highly accurate" GPS be a military GPS?! Scaaary forum!

 

[DaveC426913]

Am I the only one who immidiately thought of "Is your refrigerator running?..."

You nailed it.

 

[zoobyshoe]

Checkout the dust cloud generated in the desert hills of Mexicali [presumably].
http://www.ireport.com/docs/DOC-428979?hpt=C2

I just became aware today that Calexico had major damage. Video on TV showed split roads, traffic lights fallen over onto cars, buildings shaken to funny angles.

No people seriously injured, but the economy was already bad there, so now they're thinking it's going to be depressed for years. The downtown businesses and the city infrastructure suffered major blows.

 

[TheStatutoryApe]

What I find amusing is that the same people who take this in stride, might be the same people who think strangers always kidnap children...

You mean the candy people? I like the candy people!

But seriously, I have lived here all of my life. I have yet to be in an earthquake where, in my immediate vicinity, there was more damage than a picture that fell off the wall.

I know that there are big earthquakes and they can cause some serious damage but the vast majority of them are nothing but a bit of a shake up. Its like freaking out every time it rains because hurricanes do lots of damage.

 

[zoobyshoe]

But seriously, I have lived here all of my life. I have yet to be in an earthquake where, in my immediate vicinity, there was more damage than a picture that fell off the wall.

I know that there are big earthquakes and they can cause some serious damage but the vast majority of them are nothing but a bit of a shake up. Its like freaking out every time it rains because hurricanes do lots of damage.

The thing is, geologists have been saying that San Diego is overdue for a big one. The geological record indicates this area is the epicenter of a 7. + quake every hundred and something years, and we're about 30 years overdue. This is why each one I can feel alarms me till it's over.

 

[Frame Dragger]

The thing is, geologists have been saying that San Diego is overdue for a big one. The geological record indicates this area is the epicenter of a 7. + quake every hundred and something years, and we're about 30 years overdue. This is why each one I can feel alarms me till it's over.

Indeed, especially as "overdue" often means a larger energy release. Of course, what the news doesn't cover (not horrifying) is that faults can have that same potential sapped by a number of smaller quakes.

So.. this could be very VERY bad, or it could be you never have to see more than pictures fall. I hope (I'm guessing as you do!) for the latter.

 

[zoobyshoe]

Indeed, especially as "overdue" often means a larger energy release. Of course, what the news doesn't cover (not horrifying) is that faults can have that same potential sapped by a number of smaller quakes.

So.. this could be very VERY bad, or it could be you never have to see more than pictures fall. I hope (I'm guessing as you do!) for the latter.

Yes, the "overdue" seems to indicate things have gotten stuck on a particularly difficult spur, as it were, which would mean a much larger quake when that finally gives way. On the other hand it could mean that the past regular quakes already succeeded in grinding down a particularly difficult spur, and that is the reason there has not been another big one in the series. In any event, I once saw a map of all the faults under San Diego. It looked like a peanut butter cookie that someone had sat on: it's in a million pieces.

 

[Frame Dragger]

Yes, the "overdue" seems to indicate things have gotten stuck on a particularly difficult spur, as it were, which would mean a much larger quake when that finally gives way. On the other hand it could mean that the past regular quakes already succeeded in grinding down a particularly difficult spur, and that is the reason there has not been another big one in the series. In any event, I once saw a map of all the faults under San Diego. It looked like a peanut butter cookie that someone had sat on: it's in a million pieces.

I'm sorry, I know I shouldn't, but that last sentence had me in stitches! Of course you're absolutely right, and here's to hoping that this 100-130 years just missed a "big one" or that this fault will be less... energetic. Unlike a subduction zones, slip-strikes can have much longer periods of "calm".

 

[zoobyshoe]

I'm sorry, I know I shouldn't, but that last sentence had me in stitches! Of course you're absolutely right, and here's to hoping that this 100-130 years just missed a "big one" or that this fault will be less... energetic. Unlike a subduction zones, slip-strikes can have much longer periods of "calm".

Yeah, I guess that sounded funnier than I meant it to.

I certainly hope any large buildup of potential energy is frittered away in small quakes.

 

[Frame Dragger]

Yeah, I guess that sounded funnier than I meant it to.

I certainly hope any large buildup of potential energy is frittered away in small quakes.

I'll drink (well.. ok, I don't, but I WOULD) to that!

On a related note, the prediction now is for a very strong Atlantic hurricane season. That is NOT going to be good news for Haiti, and if we had a major quake in the USA, we would divert resources even more from those who literally couldn't live without it. Hell, they may not anyway. :sad:

 

[TheStatutoryApe]

The thing is, geologists have been saying that San Diego is overdue for a big one. The geological record indicates this area is the epicenter of a 7. + quake every hundred and something years, and we're about 30 years overdue. This is why each one I can feel alarms me till it's over.

Sorry Zoob. I do not mean to demean your, or anyones, concern regarding earthquakes. For those who have never experienced them I'm sure that even a small one is rather surprising to say the least.

 

[zoobyshoe]

Sorry Zoob. I do not mean to demean your, or anyones, concern regarding earthquakes. For those who have never experienced them I'm sure that even a small one is rather surprising to say the least.

What can I say? The ground should not be moving around.

I'm not a fan of volcanoes either.

 

[Frame Dragger]

What can I say? The ground should not be moving around.

I'm not a fan of volcanoes either.

Yeah... the latter really can be terrifying, especially the notion of something like Yellowstone blowing its top. Then again, that probably is the answer to my earlier question: you can't run from nature in the end.

 

[DaveC426913]

What can I say? The ground should not be moving around.

Duct tape to the rescuuuuuuue!