PSN-L Email List Message
Subject: Re: unusual frequency
From: Bob Hancock carpediem1@.........
Date: Mon, 3 Nov 2008 14:50:56 -0700
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:
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...."
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.
Public Seismic Network Mailing List (PSN-L)
[ Top ]
[ Back ]
[ Home Page ]