PSN-L Email List Message

Subject: RE: Locating P and S wave, suggestions needed
From: "Bob Hancock" carpediem1@.........
Date: Tue, 10 Jan 2006 21:40:09 -0700

I downloaded the file and then looked at it with the FFT option in =
I tried several different filtering options and then settled on =
out all data with a frequency longer than 1 hz.  I was unable to see
anything that looked like an earthquake in the longer frequencies.

This appears to be two separate earthquakes such as a primary event and
aftershock, rather than a P wave and S wave.  In addition, based upon =
higher frequencies of both events, they are relatively close to the =
although I would not want to hazard a guess at distance.  I have noticed
similar frequencies from nearby events both in New Jersey where I used =
live and now in Arizona. =20

The initial direction of what I perceived as the P wave is visible and =
up on both events.  As I see it, the first event occurred at 25:53.270 =
the amplitude on the P wave was 20.3.  The second event occurred at
26:13.120, and the amplitude on the P wave was 34.6.

This all becomes visible when you filter out the lower frequency data, =
expand the X axis to 10 seconds.

However, if an expert has a better answer, I will bow to them.

Bob Hancock
Three Points, AZ

-----Original Message-----
From: psn-l-request@.............. [mailto:psn-l-request@............... =
Behalf Of Paul
Sent: Tuesday, January 10, 2006 18:44
To: psn-l@..............
Subject: Re: Locating P and S wave, suggestions needed

According to my friend, he reckons they look good.  Your S looks good to =

him, but your P could be moved to coincide with the peak of the first=20
pulse, it seems to be a few samples earlier than the peak.

I'm new at this myself, so I'd like to hear some feedback too

J=F3n Fr=EDmann wrote:
> Hi all
> As I did say in my early post today, I did record a earthquake at =
> today. The earthquake mag was 3,0 on the ricther scale according to =
> icelandic met office. My problem is this that i don't think i have =
> the p and s wave properly, since this earthquake wave has two spikes,
> not one. I did think that i had correctly located the p and s waves, =
> based on the wave form I am not totally sure.
> Here is the gif file and the psn file of the recording.
> =
> (p and s markers are not set in this psn file)
> Here is a picture of the earthquake with the p and s markers as i did
> set them.
> If nothing else, I welcome suggestions on this matter.
> Regards.


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