[Boatanchors] Some Shaking Going On??

[rbethman]

See below:

On 8/23/2011 3:50 PM, Richard Knoppow wrote:
>
> ----- Original Message ----- From: "rbethman" <rbethman at comcast.net>
> To: "boatanchors" <boatanchors at mailman.qth.net>
> Cc: "Bill Stewart" <cwopr at embarqmail.com>
> Sent: Tuesday, August 23, 2011 11:21 AM
> Subject: Re: [Boatanchors] Some Shaking Going On??
>
>
>> The Epicenter is about 40 miles South of here.
>>
>> It was a 5.9 4 miles SSE of Louisa, VA.
>>
>> Try here:
>>
>> <http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/US10/32.42.-85.-75_eqs.php> 
>>
>>
>> It definitely was more than a "little earth rattling"!
>>
>> However, I've been through them in Panama, CZ, and Kodiak, Alaska.
>>
>> This is the strongest I've sat through.  No Hummel Plates or pictures
>> came off the walls.
>>
>> One picture frame fell off the dresser.
>>
>
>     Welcome to the wonderful world of earthquakes:-)
>     The notice on the USGS mailing list says its depth was 1 km but 
> the map above shows 8 km, perhaps revised. The deeper center makes 
> sense of the very wide area it was felt in and fairly low surface 
> intensity. I have lived with earthquakes for some sixty years here but 
> never really get used to them. Most are just jars like someone dropped 
> something heavy but the bad ones are very frightening. Its not usually 
> a heavy shake that tapers off but shaking that builds up for a time 
> and then tapers off or, sometimes just stops abruptly. Depending one 
> where you are they can also be noisy. Los Angeles is honeycombed with 
> small faults; usually the first clue one is there is when it breaks 
> loose and shakes. The quakes are usually near the surface so the 
> intensity can be quite high but the area is limited. The "big one" the 
> movies are so enamored of probably will never happen here because the 
> big earth faults are fairly distant, mostly we have localized smaller 
> quakes, but due to their proximity damage can be great.
>     There is a limit on how strong any earthquake can be. It is 
> established by the strength of the earth's crust. An earthquake can be 
> likened to charging a capacitor: it takes a certain amount of energy 
> to charge and then arcs over. The strength of the earth's crust is 
> such that it will break when enough energy is stored for something 
> less than a Richter 10 quake. I don't remember the record quake but 
> think it was around a 9.8, which is close to the limit.
>     Quakes on the East coast of the U.S. are fairly rare but do 
> happen. Usually they are too weak to get much attention. Earthquakes, 
> tornadoes, hurricanes, severe floods, volcanoes etc, are just little 
> reminders of the power of nature. We like to pretend we are in control 
> here but are really not.
>
>
> -- 
> Richard Knoppow
> Los Angeles
> WB6KBL
> dickburk at ix.netcom.com
>
I've been in them before, and it is really a hoot to see the responses 
of folks!  JFK Airport shutdown!  Our local Dulles and Reagan National 
continued operations!

We've know about this particular fault since about 1974.  The ONLY issue 
I see at the moment, it that the North Anna Nuclear Power Facility 
*near* the Epicenter was shown by live aircraft.  There is a steam leak 
between one reactor containment vessel and the separate powerhouse.

I remember touring that plant.  I do NOT believe that this steam leakage 
is normal.

However, that steam would be in the Secondary Loop - *NOT* the Primary 
Loop.  So it is NOT contaminated.

It so happens to have been the largest Virginia Quake in over a century!

Bob - N0DGN