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.psnM8.9 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.psnMw8.9 8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,
> Japan (GIF Image)
> 110311.054500.sobn.psnMw8.9 8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,
> Japan (GIF Image)
> 110311.054500.sobz.psnMw8.9 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
>
>
Hi Steve,

=
=A0 I looked at it, but I need to know more about its spectral response bef=
ore I can properly inverse filter it.

Bob



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









Hi=20
Bob, Did you happen to see this in the Larry's Redwood City PSN dataset=
s? If I=20
remember correctly, Niles Canyon is local=A0near Larry's Redwood=20
City=A0location and is a USGS geophone up in the hills. The data is=20
impressive.=A0 Regards, Steve Hammond PSN San Jose, Aptos=20
CA.
=
=A0
110311.054624.cni.psn=20
M8.9 7974km from Niles Canyon, CA USA, NEAR THE EAST COAST OF HONSHU, JAPAN=
 (GIF=20
Image)

=A0

  

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

=A0 I use inverse filtering to restore=20
  long-period response to my medium period sensors. On major events, even=
=20
  geophones can be transformed into long-period sensors.

=A0 For=20
  example, I downloaded the following files:

110311.=
054500.sobe.psn=20
  Mw8.9 8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,=
=20
  Japan (GIF=20
  Image)
110311.054500.sobn.psn=20
  Mw8.9 8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,=
=20
  Japan (GIF=20
  Image)
110311.054500.sobz.psn=20
  Mw8.9 8750km from Sonderborg, Denmark, Near East Coast of Eastern Honshu,=
=20
  Japan (GIF=20
  Image)

=A0 I inverse filtered from the original period of 0.22=
=20
  seconds to 20 seconds and posted the following volume file:

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

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

=A0=20
  If you integrate the data, you get peak displacements in the 3 to 4 mm ra=
nge,=20
  which seems about right.

=A0 My inverse filter utility program,=20
  WQFilter.exe, can be downloaded from http://sites.google.com/site/bobmcclure=
90

Bob