Thanks Bob thats interesting;

The report i read about ocean waves being
the cause was much more recent than 1993
I think it was a study from sometime in the the 2000s.
I wish i could remember where I saw it
but i cant. It might have been in a Discover
magazine. and not an official government thing.
Lately Ive been spending most my time
playing games like BattleField2/2142. My computer is
quickly becoming obsolete so i want to get the
most from it before it can no longer play these types of games.
It will always be able to look at seismic stuff
but not so for these computer games.
Things are revolutionary instead of evolutionary
and I am unable to keep up with it all.

geoff

----- Original Message ----- 
From: "Bob Hancock" 
To: 
Sent: Monday, November 03, 2008 2:50 PM
Subject: Re: unusual frequency


> Geoff -
> 
> You are correct about the background noise.  For more information,.  I  
> would suggest that you download and read the following article from  
> the Albuquerque Seismological Laboratory:
> 
> OFR 93-322:  Observations and Modeling of Seismic Background Noise    
> Use the following link:
> 
> http://earthquake.usgs.gov/regional/asl/pubs/files/ofr93-322.pdf
> 
> On page 14, the report states:
> 
> "...the most dominate features [Earth Noise] being the natural  
> microseisms in the period range from about 1 to 20 sec with peaks at 5  
> sec and 18 sec, and the Earth tides with peaks at semi-diurnal and  
> diurnal periods.  The rounded low-noise peak in the long-period band  
> at a period of about 120 sec appears to be a real and significant  
> noise feature, it cause unknown...."
> 
> Cheers
> 
> Bob Hancock
> 
> 
> 
> On Nov 3, 2008, at 8:29 AM, Geoff wrote:
> 
>> I have heard "somewhere on the internet" that 5 second period  
>> microseismic waves
>> are generated by waves in the oceans waters at certain resonant depth
>> and radiate for very long distances.
>> This has been determined through scientific observations.
>> Not to say other phenomena do not also create
>> 5 second waves.
>> I often see such waves relating to weather fronts coming from
>> the pacific before it hits arizona.
>> And my system was designed only to see
>> 3 second to 2Hz range so they must be
>> quite large in magnitude.
>> Its not weather over land but weather over ocean.
>> geoff
>>
>>>
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