After looking at Niles Canyon data I went back and looked at my HS10
geophones records (ATZ, ATE and ATN) and relaized that they had recorded
the P wave to S arrival some 8,019km from Aptos, CA to Japan. In 21
years of operation I cannot recall ever seeing them record any events
past 1,000 miles before. I posted the data to Larry's site. Regards,
Steve Hammond PSN San Jose, Aptos CA

-----Original Message-----
From: psnlist-request@..............
[mailto:psnlist-request@............... On Behalf Of Bob McClure
Sent: Sunday, March 13, 2011 2:35 PM
To: psnlist@..............
Subject: Re: Inverse filtering example


Hi Steve,

  I looked at it, but I need to know more about its spectral response
before I can properly inverse filter it.

Bob


On Sun, Mar 13, 2011 at 4:32 PM, Stephen Hammond
 wrote:


Hi Bob, Did you happen to see this in the Larry's Redwood City PSN
datasets? If I remember correctly, Niles Canyon is local near Larry's
Redwood City location and is a USGS geophone up in the hills. The data
is impressive.  Regards, Steve Hammond PSN San Jose, Aptos CA.
 
110311.054624.cni.psn
  M8.9 7974km
from Niles Canyon, CA USA, NEAR THE EAST COAST OF HONSHU, JAPAN (GIF
Image)
 

 

-----Original Message-----
From: psnlist-request@..............
[mailto:psnlist-request@............... On Behalf Of Bob McClure
Sent: Sunday, March 13, 2011 1:10 PM
To: psnlist@..............
Subject: Inverse filtering example


  I use inverse filtering to restore long-period response to my medium
period sensors. On major events, even geophones can be transformed into
long-period sensors.

  For example, I downloaded the following files:

110311.054500.sobe.psn
  Mw8.9
8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,
Japan (GIF Image)
 
110311.054500.sobn.psn
  Mw8.9
8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,
Japan (GIF Image)
 
110311.054500.sobz.psn
  Mw8.9
8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,
Japan (GIF Image)
 

  I inverse filtered from the original period of 0.22 seconds to 20
seconds and posted the following volume file:

110311.055500.sobx.psn
  * M8.9
8750km from Sonderborg, Denmark [Inverse Filtered], Near East Coast of
Eastern Honshu, Japan (GIF Image)
 

which can be looked at or downloaded from
http://www.seismicnet.com/cgi-dos/event.exe

  If you integrate the data, you get peak displacements in the 3 to 4 mm
range, which seems about right.

  My inverse filter utility program, WQFilter.exe, can be downloaded
from http://sites.google.com/site/bobmcclure90

Bob










After=20
looking at Niles Canyon data I went back and looked at my HS10 geophones =
records=20
(ATZ, ATE and ATN) and relaized that they had recorded the P wave to S =
arrival=20
some 8,019km from Aptos, CA to Japan. In 21 years of operation =
I cannot=20
recall ever seeing them record any events past 1,000 miles before. I =
posted the=20
data to Larry's site. Regards, Steve Hammond PSN San Jose, Aptos=20
CA

  

  
-----Original Message-----
From:=20
  psnlist-request@.............. [mailto:psnlist-request@............... =
On=20
  Behalf Of Bob McClure
Sent: Sunday, March 13, 2011 2:35=20
  PM
To: psnlist@..............
Subject: Re: Inverse =

  filtering example

Hi Steve,

  I looked at =
it, but I=20
  need to know more about its spectral response before I can properly =
inverse=20
  filter it.

Bob


  
On Sun, Mar 13, 2011 at 4:32 PM, Stephen =
Hammond <shammon1@.............>=20
  wrote:

  

    

    
Hi Bob, Did =
you happen to=20
    see this in the Larry's Redwood City PSN datasets? If I remember =
correctly,=20
    Niles Canyon is local near Larry's Redwood City location =
and is a=20
    USGS geophone up in the hills. The data is impressive.  =
Regards, Steve=20
    Hammond PSN San Jose, Aptos CA.
    
 
    
110311.054624.cni.psn M8.9 7974km from Niles =
Canyon, CA=20
    USA, NEAR THE EAST COAST OF HONSHU, JAPAN (GIF Image)

    

    

    

    
 
    

      

      
-----Original=20
      Message-----
From: psnlist-request@.............. [mailto:psnlist-request@..............] On Behalf =
Of Bob=20
      McClure
Sent: Sunday, March 13, 2011 1:10 =
PM
To: psnlist@..............
Subject: =
Inverse=20
      filtering example

  I use inverse =
filtering to=20
      restore long-period response to my medium period sensors. On major =
events,=20
      even geophones can be transformed into long-period =
sensors.

 =20
      For example, I downloaded the following files:

110311.054500.sobe.psn Mw8.9 8750km from =
Sonderborg,=20
      Denmark, Near East Coast of Eastern Honshu, Japan (GIF Image)
110311.054500.sobn.psn Mw8.9 8750km from =
Sonderborg,=20
      Denmark, Near East Coast of Eastern Honshu, Japan (GIF Image)
110311.054500.sobz.psn Mw8.9 8750km from =
Sonderborg,=20
      Denmark, Near East Coast of Eastern Honshu, Japan (GIF Image)

  I inverse filtered =
from the=20
      original period of 0.22 seconds to 20 seconds and posted the =
following=20
      volume file:

110311.055500.sobx.psn * M8.9 8750km from =
Sonderborg,=20
      Denmark [Inverse Filtered], Near East Coast of Eastern Honshu, =
Japan (GIF Image)

which can be looked at or =
downloaded=20
      from http://www.seismicnet.com/cgi-dos/event.exe

&n=
bsp;=20
      If you integrate the data, you get peak displacements in the 3 to =
4 mm=20
      range, which seems about right.

  My inverse filter =
utility=20
      program, WQFilter.exe, can be downloaded from http://sites.google.com/site/bobmcclure90

Bob<=
BR>