Hi Brett
I made a file from 12:00 UTC to 24:00 UTC on the 3/11. I see a fft peak at ~ 245 
sec. 

see 
http://www.seismicvault.com/sitebuilder/images/110311_120000_ch1_psn_fft.gif
Regards
Barry






________________________________
From: Brett Nordgren 
To: psnlist@..............
Sent: Fri, March 11, 2011 8:22:52 PM
Subject: Re: The Earth is Ringing

Gary,

Yes, we're watching them, too.  The whole earth can vibrate in many modes.  The 
lowest has about a 20 minute period and I think that some oscillation modes have 
been observed up to about a 200-second period.  Though I doubt if it means 
anything, the 4S0 mode has a period of about 243 seconds.  We're also trying to 
figure out if it could be something else, though that could possibly be the 
explanation.

Brett



At 08:17 PM 3/11/2011, you wrote:

After 19 hours the earth's ring is starting to subside. I measure a period of 
about 240 seconds or so. Is that the period of the earth's natural frequency. 
All day my vertical seismometer's most sensitive output has been ringing like a 
bell. It's difficult to see through the output of the initial M8.9 quake and all 
the aftershocks.
>Gary
> 
> 
> 
> 
> 
> 
> 
> 
>Gary Lindgren
>585 Lincoln Ave
>Palo Alto CA 94301
> 
>650-326-0655
> 
>www.blue-eagle-technologies.com   Check out Lastest Seismometer Reading
>cymonsplace.blogspot.com 
>sites.google.com/site/seismicsensorinfo/Home    Design Details for New Vertical 
>Seismometer 
>
> 


Hi Brett
I made a file from 12:00 UTC to 24:00 UTC on the 3/11. I see a fft peak at ~ 245 sec. 
see 
http://www.seismicvault.com/sitebuilder/images/110311_120000_ch1_psn_fft.gif
Regards
Barry



From: Brett Nordgren <brett3nt@.............>
To: psnlist@..............
Sent: Fri, March 11, 2011
 8:22:52 PM
Subject: Re: The Earth is Ringing




Gary,


Yes, we're watching them, too.  The whole earth can vibrate in many
modes.  The lowest has about a 20 minute period and I think that
some oscillation modes have been observed up to about a 200-second
period.  Though I doubt if it means anything, the
4S0 mode has a period of about
243 seconds.  We're also trying to figure out if it could be
something else, though that could possibly be the explanation.


Brett





At 08:17 PM 3/11/2011, you wrote:

After 19 hours the earth's ring
is starting to subside. I measure a period of about 240 seconds or so. Is
that the period of the earth's natural frequency. All day my vertical
seismometer's most sensitive output has been ringing like a bell. It's
difficult to see through the output of the initial M8.9 quake and all the
aftershocks.

Gary

 

 

 

 

 

 

 

 

Gary Lindgren

585 Lincoln Ave

Palo Alto CA 94301

 

650-326-0655

 


www.blue-eagle-technologies.com   Check out Lastest
Seismometer Reading


cymonsplace.blogspot.com 


sites.google.com/site/seismicsensorinfo/Home    Design
Details for New Vertical Seismometer