Feeling a little Shaky This Morning

Just getting ready to access ETS and felt a definite shock -appears to be a 4.7 in Los Angeles (Westwood) time was 6:25 AM. Not the 9.0 in a current thread, but it definitely got my attention. Details to follow....

Yep, Recent Earthquakes in CA & NV

Edit:
and if you click on the big red square you go to:
map centered on LA and you see Northridge right next to the big red square. Northridge... where have I heard that before ???

Stay safe everyone!

At 8.5 km depth, possibly a left-lateral associated with one of your E-W faults:
M4.4 - 9km NNW of Westwood, California

To interpret the "beach ball" focal mechanism diagram, see A Primer on Focal Mechanism Solutions

If you are feeling all scientific, you can fill out the "Did you feel it?" page.

I actually got to the USGS site before they had posted info on this, and I had a go at the "Did you feel it" section. Info was up within about five minutes of the quake - pretty impressive.

I was finally able to get to my first cup of morning tea after this shocking interruption.

The first estimates of magnitude, epicenter, depth, focal mechanism, etc are all done automatically by software, using a network of seismometers. This is very useful technology. For example the tsunami warning centers use this sort of thing to decide if they need to put out a warning. Later analysis by humans can refine and improve those estimates, so you might read tomorrow that the magnitude is slightly different from this first estimate.

The severity of shaking one feels is somewhat dependent on local geology. For example, bedrock behaves differently than artificial fill. The "did you feel it" data is useful for estimating risk in future quakes, for various local areas. Also for different kinds of structures. A single observation doesn't mean a lot, but large numbers of "crowd sourced" observations from around an area start to build a picture. I always try to fill out the "did you feel it" when I feel a quake.

Science is cool!

Glad to see you're okay and it wasn't too bad.

Thank you, Phaedrus.

I turned on the TV and whatever damage occurred wasn't enough to make any headlines. One station did show some footage of their news room staff diving under their desks.

I am not a fan of the local TV coverage (way too superficial), but they are very good at covering disasters....Practice makes perfect.

Hey, this is California, after all. News stations jump to dramatic "Storm Watch" coverage when a little bit of rain starts to fall this winter.

We go to so-and-so in Malibu. "Well, as you can see, it's raining."

And now to so-and-so in Long Beach. "Same thing here. It's raining. Back to the studio..."

Do we really need the news to tell us that it's raining lightly outside? LOL

Of course! Especially when the weather person qualifies as rather decent eye candy. Isn't that what the news is all about?

LA times posted the first news report on this small quake earlier today. What is interesting, the news report was posted/aided by Quakebot.

Ken Schwencke, a journalist and programmer for the Los Angeles Times, was jolted awake at 6:25 a.m. on Monday by an earthquake. He rolled out of bed and went straight to his computer, where he found a brief story about the quake already written and waiting in the system. He glanced over the text and hit “publish.” And that’s how the LAT became the first media outlet to report on this morning’s temblor. "I think we had it up within three minutes."

If that sounds faster than humanly possible, it probably is. While the post appeared under Schwencke’s byline, the real author was an algorithm called Quakebot that he developed a little over two years ago.

The LAT had their story up about as fast as the USGS posted the data on their website. I was up and browsing when I felt the shock, went to the USGS site, and saw nothing until about 6:40 or so..\

I could have used something like quakebot when I had to write term papers...

Speaking of feeling shaky, this woman needs to move somewhere seismically and otherwise quiet: like North Dakota.

http://losangeles.cbslocal.com/2014/03/17/earthquake-nerves-could-impact-mental-health/




.

Interesting quake follow-up article: what geologists don't know about the fault system underneath southern California probably eclipses what they do know.


http://www.latimes.com/local/la-me-0318-earthquake-los-angeles-20140318,0,300057.story#axzz2wGXI21P9


"Monday's 6:25 a.m. temblor showed that for all that is understood about quakes, much remains unknown. Southern California's most destructive earthquakes in the last generation — the 5.9 Whittier Narrows in 1987 and the 6.7 Northridge in 1994 — occurred on faults unknown to scientists before the shaking began."


.

A good colleague and friend of mine is actively engaged in earthquake related research, doing his dissertation on a fault in my neighborhood. I am sure he would agree completely with your statement.

Amazing! Though if I were a reporter I'd be pretty nervous right now.
-Blast

In seismic terms, North Dakota is definitely a better bet than California, but the potential for earthquakes is virtually universal. Fracking is on the increase in ND, and there do seem to be some rather strong correlations between fracking and earthquakes, some of which reach in Richter 4 and 5 levels.

Earthquakes remind us that life is unpredictable and that many events are beyond our control. Sometimes the best we can do is play the odds, prepare for the worst, and hope for the best.

Incidentally, the nascent earthquake warning system worked for this event. Although a longways from full implementation, it did give some advance warning...It will get better in the future.

Not to worry. Compare this article that appeared in the LA Times this morning - http://www.latimes.com/local/lanow/la-me-ln-earthquake-foreshock-20140317,0,2194994.story#axzz2wMPXivxJ.

It gives context, not just the bare bones of the event. The earlier article was worthwhile, as well. When I felt the shock, my immediate concern was whether this was a small quake close by, or a monster at a distance. Both the USGS site and the LA Times had that information right away, allowing me to get back to guzzling my morning tea.

LOL..

http://www.youtube.com/watch?v=EPKEgO4Ojmk

or how the BBC News media might handle these type of events (probably NOT.. )

http://www.youtube.com/watch?v=oP-rkzJ6yZw

The Atlantic has an article with a bit more detail on "Quakebot".

To me the real magic isn't Quakebot, which after all just reformats USGS a USGS data release. The most impressive story is how the USGS and cooperating universities and other organizations is able to network all those seismometers, and process the data to generate the info Quakebot gets. The software must first recognize that an earthquake has occured (rather than random noise), recognize the same earthquake on at least two other seismometers, solve a three dimensional problem to locate the epicenter and depth, also compute the magnetude, and do it all in real time.

As I mentioned upthread, more or less the same approach is used by the tsunami warning centers quickly decide whether to send out a warning. A couple of years ago I toured the Alaska and West Coast Tsunami Warning center in Palmer, AK (recently renamed the "National Tsunami Warning Center"). Really big earthquakes shake for several minutes, and one of the staff told me that when the big Japan earthquake happened, they were sending out the initial alert before the ground stopped shaking in Japan!

Another practical use of this type of technology is to give a short local warning of a big earthquake. It can take 30 seconds or more for the waves to travel across a city to nearby areas. This is enough time for people to duck and cover before the shaking starts. I've read that in Japan, seismomters closer to the epicenter sent warnings to further away areas, which gave people some warning.