Earthquake Shakes San Francisco Bay Area

[buffster]

This morning at 4:42 a.m., we experienced a fairly violent shake in the San Francisco Bay Area. The temblor, with a magnitude of 4.2--a relatively mild quake, was epicentered only 2 miles East/Northeast of Oakland, at a shallow depth of .2 miles. (That's why we felt such strong shaking.) I've included a link if anyone is interested in reading more about it.

http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/nc40199209.php

 

[buffster]

Quake Update

Follow these links for up-to-date info on the quake...

http://cbs5.com/

http://www.kron.com/
http://quake.wr.usgs.gov/recenteqs/Quakes/nc40199209.htm

 

[63getelevision]

San Fran Quake

I hope you are OK. What a miserable way to be woken up.

 

[hoover1060]

YEOWWW!!

Earthquakes scare the daylights out of me...

of course in the midwest we have tornadoes in the spring and summer, which are just as destructive as an earthquake..

However there are no sirens that sound before an earthquake...

be safe Mike!! Keep us posted!

 

[sudsmaster]

It was pretty mild here, about 5 miles south of there.

 

[sudsmaster]

The depth was 3.6 miles, +/- .2 miles.

 

[buffster]

Quake

Thanks for the concern guys. Jeff, I heard that you've been experiencing bad weather in your area, including reports of possible tornados. I hope you and Michael are safe as well.

Rich, thanks for the correction. I didn't proof my post carefully. Where are you located?

I definitely felt a good jolt here--it woke me up. And, I'm on bedrock--safest place to be during a quake. Typically, a 4.2 is no big deal, but it probably felt more significant for many because this was such a shallow quake and the epicenter is so close. Apparently, many people are reporting minor damage over in Oakland and Piedmont. They're reporting that it was on the Hayward fault.

 

[oxydolfan1]

I called my friend in Martinez, California about a half-hour ago to check and left a message, without fully realizing the time difference!

I hope I haven't committed another faux-pas!

 

[maytagbear]

Mercy!

Of course I am concerned, but I am not going to worry.....yet.

I hope all of our Bay Area members are well and that their residences sustained no serious damage.

Lawrence/Maytagbear

HUMOUR ALERT:

Is this what Carole King meant??

 

[frontaloadotmy]

Yes Lawrence

That's eggszackly what Carol meant!!
4.2 is hardly enough to make the vertical blinds sway
in a 12 story office building. Agood reminder that the big one is comin'.

 

[frigilux]

Hope all our San Francisco-area family are safe and sound! Tornadoes are destructive, but at least you can take shelter in the basement. When the earth shimmies, there ain't no hidin' from it!

 

[rapidry1000]

Slept right through another quake. I'm on bedrock in a ranch style house in one of the hills of San Francisco.

 

[buffster]

Bedrock

James, we must be neighbors because, as far as I know there's only one hill in the city that's bedrock. They took rock out of my hill to build the runways at SFO.

M.

 

[rapidry1000]

I live on the Diamond Heights/Noe Valley border. When the homes were built, the developers in Diamond Heights had to dynamite the hill to grade and realign the streets to conform to the contour of the hills of Diamond Heights.

 

[rp2813]

Didn't feel a thing down here near Los Gatos, which is par for the course with a shaker of this magnitude and that distance away. I suppose if I had been awake I might have felt a bit of a jiggle, but that's about all.

Just another reminder that the Hayward is looooong overdue to break loose and that it will likely happen during our lifetimes. THAT is going to make Loma Prieta look like child's play, I'm afraid.

Ralph

 

[frontaloadotmy]

M.

I lived on Carmelita St. 3rd house from Duboce Park
on the West side 12 years during the Loma Prieta 1989
quake. The house was built in about 1899 or 1900 on brick
foundation and had almost no evidence of quake activity
06 forward. There's gobs of bedrock in the city still.
You definitely don't want to be downtown or in the Marina
for the big one, I think the dangerous freeeways have been
torn down or retrofitted since '89. But I do hope I am not there when the big one hits, no matter when!!!!

 

[tlee618]

I am so glad to hear that all of you are alright!! We had one back in Illinois one time and it really scares one!!

 

[sudsmaster]

Like I said, I'm about five miles south of the epicenter, just south of Oakland. I was already awake for the quake, but still in bed. I noticed some movement of the bed and some windows rattling, but as quakes go, from my location, this one was very mild.

I have experienced quakes in homes built on bedrock, and they sometimes were quite a jolt. Homes built on softer soil tend to have a milder movement, however, there are other dangers associated with softer soils, such as harmonic amplification of the quake waves, as well as liquifaction and ground failure. Location also plays a big part. The Marina in SF and the Cypress Freeway Structure in Oakland were about 80 miles from the Loma Prieta epicenter, but experienced destructive earth movement because of the harmonic amplification, as well as a lens effect from a bowl shaped bedrock deep below the softer alluvial soils and landfill. A home can be right beside a fault and not have much if any damage, while a home miles away can collapse.