Interesting EQs near Los Angeles

Herding Cats

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So, I'm not sure what this means, if anything, but Yorba Linda has had two separate EQs measuring 4.5 in the last 12 hours or so. I did not feel them, and they were "small" enough for me to not have been worried had I felt them.

What's interesting, however, is that these are two separate events. I suppose the second one could be called an aftershock, but it's quite unusual to have an aftershock equal to the main shock.

Here's the map; you can click in on the left side for a list of current eqs...
http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/US2/33.35.-119.-117.php

There have been quite a few smaller shakers that I put into the catagory of aftershocks measuring 2.5 or less. There has been an aftershock close to 3 (I think a 2.9), which is a "normal" size aftershock.

The general rule of thumb is that aftershocks, being earth resettling after a move, will not be quite as large, usually a full richter scale point less, than the main shock. Of course there are exceptions, but still, generally, it's a time/strength thing. The longer the time goes by, the less high the aftershock will be.

Why am I posting something that I didn't feel, and wouldn't have been concerned about had I felt it?

Well, two things.

Romeo, my beagle, has been acting a tad anxious. He's always on edge (he's the medical experimental lab dog that has his own thread in News that Makes You Smile...), but it's kind of different; almost like he doesn't want to lose sight of me or Grace (my Newfoundland). He rarely comes into the bathroom, but he was there this morning with me...and when I leave the living room (it's gated), he goes right to the gate and watches me.

And second, of course, is the weirdness of the identical magnitude of the second quake some 10ish hours later. It was a different locale - about 1 km away from the first quake - and an identical mag, which makes me think that there is the possibility that BOTH of these quakes are foreshocks.

It's rare to have a clear foreshock...or at least, one that's near relative in time to a larger magnitude shock. But if there is a higher mag shock in the general vicinity, I'd say that this is a good set of foreshocks.

And just as a note, it's very hot (and going to get much hotter) right now, and still...very little wind or breeze. Of course it's August, and it's the hottest month of the year here, but there is still what's colloquially termed EQ weather (hot, humid, and still...). All the scientists say there is no such thing as EQ weather, but it's found to be talked about far back, into the local Native American lore. So perhaps there is something to it.

See, now that I've posted it, it won't happen. LOL. Because if I didn't post, it would for sure happen. ROFL. That's the way things go.

Just thought I'd mention it. It's always a good time to review emergency preparedness, and I've done that. So now it's just a bit of a waiting game.

Best-
Herding Cats
 
So, I'm not sure what this means, if anything, but Yorba Linda has had two separate EQs measuring 4.5 in the last 12 hours or so. I did not feel them, and they were "small" enough for me to not have been worried had I felt them.

What's interesting, however, is that these are two separate events. I suppose the second one could be called an aftershock, but it's quite unusual to have an aftershock equal to the main shock.

Here's the map; you can click in on the left side for a list of current eqs...
http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/US2/33.35.-119.-117.php

There have been quite a few smaller shakers that I put into the catagory of aftershocks measuring 2.5 or less. There has been an aftershock close to 3 (I think a 2.9), which is a "normal" size aftershock.

The general rule of thumb is that aftershocks, being earth resettling after a move, will not be quite as large, usually a full richter scale point less, than the main shock. Of course there are exceptions, but still, generally, it's a time/strength thing. The longer the time goes by, the less high the aftershock will be.

Why am I posting something that I didn't feel, and wouldn't have been concerned about had I felt it?

Well, two things.

Romeo, my beagle, has been acting a tad anxious. He's always on edge (he's the medical experimental lab dog that has his own thread in News that Makes You Smile...), but it's kind of different; almost like he doesn't want to lose sight of me or Grace (my Newfoundland). He rarely comes into the bathroom, but he was there this morning with me...and when I leave the living room (it's gated), he goes right to the gate and watches me.

And second, of course, is the weirdness of the identical magnitude of the second quake some 10ish hours later. It was a different locale - about 1 km away from the first quake - and an identical mag, which makes me think that there is the possibility that BOTH of these quakes are foreshocks.

It's rare to have a clear foreshock...or at least, one that's near relative in time to a larger magnitude shock. But if there is a higher mag shock in the general vicinity, I'd say that this is a good set of foreshocks.

And just as a note, it's very hot (and going to get much hotter) right now, and still...very little wind or breeze. Of course it's August, and it's the hottest month of the year here, but there is still what's colloquially termed EQ weather (hot, humid, and still...). All the scientists say there is no such thing as EQ weather, but it's found to be talked about far back, into the local Native American lore. So perhaps there is something to it.


See, now that I've posted it, it won't happen. LOL. Because if I didn't post, it would for sure happen. ROFL. That's the way things go.


Just thought I'd mention it. It's always a good time to review emergency preparedness, and I've done that. So now it's just a bit of a waiting game.

Best-
Herding Cats

Hi Herding Cats and Sleuthers!:seeya:

I am a So. Cal. Gal, too and hadn't heard about the two Yorba Linda 4.5 quakes.

But I am ALWAYS interested in quakes in So. Cal. due to the expectations of the "Next Big One"!

BBM
In reading your post... I agree that EQ's DO seem to happen during hot, still days... I have heard it referred to as "Shake and Bake" lol.

BBM
And I am glad you DID mention it here on WS because maybe now you sort of "jinxed" the Big Quake, and it won't happen! :great:
 
My mom lives in Anaheim Hills, just up the road from Yorba Linda. She called me about an hour ago. Said that last night's quake was almost like a "boom", different than the rolling or shaking quakes. She's a little anxious right now, as am I. The earthquake map is showing a lot of aftershocks, but it seemed to have calmed down about 45 minutes ago.

I'll be monitoring this, it is very odd. Stay safe!
 
Romeo may be onto something. Be safe - will be watching with interest to see what develops.
 
Totally agree with the earthquake weather, and that it almost never happens.

Didn't feel either one in San Clemente - going to buy water today though.

(Where we live now we feel a lot of Camp Pendleton's artillery booms, not sure I would have recognized the earthquake at that level!)
 
I often joke that it takes a 5.0 or greater for it to both make me move my hiney and/or make the news. I caught a quick comment about it on the morning news, but nothing in depth.

It's a CA thing...we're really used to "smallish" quakes that often, we don't notice them, or, if we notice them, we think they're either big trucks, or like Charlie said, if near a base, some artillery fire. LOL.

Leilei, the "boom" rather than the roll is what you feel when you're close to the epicenter. When you're a ways away, and it still is a boom rather than a roll, that's when you can tell what kind of quake it is...a slipthrust (roll) or a fracture (up/down). Near the epicenter, it's **always** up/down...but a bit farther out, the energy translates to a rolling, rocking motion.

Tell your mom not to be too anxious. Like I said, I've jinxed it now, so it of course won't happen. But always make sure that emergency supplies are near to hand...it never hurts, right?

Best-
Herding Cats
 
Romeo may be onto something. Be safe - will be watching with interest to see what develops.

He's such a character...he really is. I've had the sprinkler folks out yesterday and today, so he might be reacting to that (he gets very scared with spanish speaking guys...), but he also might be sensing something.

He also climbed into bed last night, too. He will take a nap with me, but it's fairly unusual for him to want to snuggle at bedtime. He likes his own bed. LOL.

Gracie, OTOH, is practicing holding the floor down. Sprawled out, as wide as possible, belly to the ceiling, trying to survive the heat. I haven't had her during a quake, so I don't know her behavior, but she's not anxious at all. Of course, she's a super mellow dog, so...who knows.

Best-
Herding Cats
 
Poor Gracie, so darn hot for long or thick haired dogs this time of year.

We actually had to get Bear sheared because he was so darned uncomfortable. I know they say not to do that but I couldn't take watching him struggle with the heat anymore.

He was NOT a happy camper. He wandered around for weeks after the "new do" as if he'd lost his best friend. He moped around as if he was no longer a tough guy and unsure how to carry himself without his mass of fur.
 
I often joke that it takes a 5.0 or greater for it to both make me move my hiney and/or make the news. I caught a quick comment about it on the morning news, but nothing in depth.

It's a CA thing...we're really used to "smallish" quakes that often, we don't notice them, or, if we notice them, we think they're either big trucks, or like Charlie said, if near a base, some artillery fire. LOL.

Leilei, the "boom" rather than the roll is what you feel when you're close to the epicenter. When you're a ways away, and it still is a boom rather than a roll, that's when you can tell what kind of quake it is...a slipthrust (roll) or a fracture (up/down). Near the epicenter, it's **always** up/down...but a bit farther out, the energy translates to a rolling, rocking motion.

Tell your mom not to be too anxious. Like I said, I've jinxed it now, so it of course won't happen. But always make sure that emergency supplies are near to hand...it never hurts, right?

Best-
Herding Cats

Thanks, she will be fine :) I don't think she's ever been that close to an epicenter before, so she's a little shaken up (haha). Her neighbors are out of town, so she went to check on their cat. Cat was nowhere to be found and is probably holed up in a closet or something.

I grew up in SoCal, but spent a year or so in Palm Springs. The two biggest quakes I've been in were there, and yes, it was hot as heck at the time. Was in an elevator when one of them hit - not one of my favorite memories lol.

They're still getting some after-shocks in YL, going to continue to monitor for my own peace of mind :)
 
Poor Gracie, so darn hot for long or thick haired dogs this time of year.

We actually had to get Bear sheared because he was so darned uncomfortable. I know they say not to do that but I couldn't take watching him struggle with the heat anymore.

He was NOT a happy camper. He wandered around for weeks after the "new do" as if he'd lost his best friend. He moped around as if he was no longer a tough guy and unsure how to carry himself without his mass of fur.

She is indeed miserable. But she's also staying in about 80% of the time - along with Romi. The AC is running, so I expect a high bill, but she's happy most of the time. Right now, she's sprawled out on the tiled floor in the bathroom - one of her favorite spots.

I do occasionally consider trimming her, but I hear so much negatives about that I just can't bring myself to do it. Between the emotional stuff that they seem to experience (as you noted with Bear) and the risk that their hair may not grow back the same way, I am sooooo hesitant to do anything more than a wee belly trim for Gracie.

Romi, of course, is short haired, so is doing fine, although he, too, hates the heat (and isn't used to it; this is his first summer outside of a medical testing facility, so is experiencing it for the first time...).

Leilei, of course, monitor away. What I'm seeing now is a fairly normal pattern of aftershocks. If you compare those with the outlier of that 4.5 6-7 hours ago, you will see what I mean with the weirdness.

I've been in quite a few large shakes, and no, they're not fun at all. Not when they're good sized. Kinda cool when they're small and you're sure they won't get larger, but not really. I remember one of the aftershocks of the '94 quake - I was outside, with a toddler (not mine; watching him for a friend). The aftershock hit, I tackled the toddler on the driveway and tucked him under me, and then their dog came and laid on top of the two of us, and we all just kind of laid there, feeling everything.

I remember looking up and seeing the waves rolling through the concrete; the cars bouncing like they were from the 'hood; and the trees swaying. I remember looking up at the chimney and praying "please don't let that come down on us..." (it didn't).

Yeah, it was a very scary time. It was one of the really big ones (close to 6, iirc), and while I was able to control my emotions afterward because of the toddler, it was a hard thing.

Best-
Herding Cats
 
I just came back from a quick errand----so freaking HOT outside. Seriously.

But on KFI radio they said there has been THIRTY small quakes in that area in the past 48 hours. YIKES.

Born and raised in Cali, I have been through a lot of quakes. Some of them in Northern California. I grew up in the SF BaY Area and there were always a lot of quakes up there.
 
Thanks, she will be fine :) I don't think she's ever been that close to an epicenter before, so she's a little shaken up (haha). Her neighbors are out of town, so she went to check on their cat. Cat was nowhere to be found and is probably holed up in a closet or something.

I grew up in SoCal, but spent a year or so in Palm Springs. The two biggest quakes I've been in were there, and yes, it was hot as heck at the time. Was in an elevator when one of them hit - not one of my favorite memories lol.

They're still getting some after-shocks in YL, going to continue to monitor for my own peace of mind :)
BBM

In an elevator in an Earthquake!!! :gasp:

One of my worst nightmares!!!
 
BBM

In an elevator in an Earthquake!!! :gasp:

One of my worst nightmares!!!

Me too. But my ultimate WORST nightmare is underground parking lots. I HATE to use them and I almost never go in them if I can help it. lol
 
I felt the one last night. The husband and I were upstairs on our computers at the time, and my monitor just started bouncing. I didn't feel the one today when I was at the office, but I was running around a lot. One of my coworkers felt it and asked me if I had.
 
I must be dense! I had no idea what EQs meant in the title of this thread! Hope the 30 small quakes do not turn into being a precursor of anything to come.

I would be a nervous wreck if I lived out there. Stay safe!
 
I must be dense! I had no idea what EQs meant in the title of this thread! Hope the 30 small quakes do not turn into being a precursor of anything to come.

I would be a nervous wreck if I lived out there. Stay safe!

I was just discussing this with my DW before reading your post and said it is probably pre-quake, if the first two were 4.5 I don't think it was "the" EQ and an aftershock. Also at the beginning of the year I predicted in a thread (in the jury room maybe?) that in 2012 CA and the midwest would both witness severe quakes. :what:
 
HD and everyone in S. Cali, please stay safe! I did want to address the weather topic which I thought was interesting that you mentioned hot, humid weather possibly being a factor. We had one in March 2011 measuring 4.3 and for those who don't know, March is still a fairly cool month up here in Canada with snow still on the ground so I wonder if perhaps EQ weather really is a non factor when it comes to Earthquakes as the scientists claim (??)

http://www.cbc.ca/news/canada/montreal/story/2011/03/16/earthquake-western-quebec.html

Anyway, just thought I'd share another perspective. I guess EQ really are unpredictable. Scary.

Stay safe :hug:
 
HD and everyone in S. Cali, please stay safe! I did want to address the weather topic which I thought was interesting that you mentioned hot, humid weather possibly being a factor. We had one in March 2011 measuring 4.3 and for those who don't know, March is still a fairly cool month up here in Canada with snow still on the ground so I wonder if perhaps EQ weather really is a non factor when it comes to Earthquakes as the scientists claim (??)

http://www.cbc.ca/news/canada/montreal/story/2011/03/16/earthquake-western-quebec.html

Anyway, just thought I'd share another perspective. I guess EQ really are unpredictable. Scary.

Stay safe :hug:

That's the biggest thing with EQs...there is no way to predict them. They just happen. Science has done it's best, and we still don't know enough to predict a quake. And that's also why it's so scary.

With most other natural disasters, there is at least a bit of warning, usually. But not EQs.

I think that weather may play a part; also, moon phases, sun flares, and butterfly wings in Papua.

No, weather is not a reliable predictor...we have lots of hot, humid, still days that do not have EQs embedded in them; and we've had cold, snowy (like n/t said) times that have had quakes. But who really knows? It's been noted for centuries, but then, we haven't been able to prove it, either.

I checked the map this morning, and I'm relieved that the aftershock patterns look fairly regular. But I'm still bothered by the pair of 4.5s...that's pretty unusual by itself.

Best-
Herding Cats
 
Just as a reminder from Kate Hutton. earthquakes happen way below the earth's surface so they are not affected by the outside temperature or the temperature that we feel.
So the fact that it has been so hot is not truly relevant. Alaska has more EQ activity than CA.
She also said these may be along the Whittier fault but they were not 100% consistent with that fault so this is probably a new fault. But there are lots of new faults so this is not particularly alarming or anything.


But there is always a 100% chance another eq will strike at any time.

When 2 back to back like that they are called doublets for your trivia collection. :)
 

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