I met a gentleman via email, Matt, that has a number of older =
seismometers for sale, with some on EBay, a Kinemetrics vertical and =
horizontal and a ranger.  One of the item numbers is 110369876034, that =
listing will take you to the other two he has.  He also would like help =
in identifying a number of other seismometers he has that he has not =
listed as yet.  The URL for the pictures is =
http://s271.photobucket.com/albums/jj139/shostang/Seismology/  He would =
really appreciate list members help in identifying the units he has.
  ----- Original Message -----=20
  From: Bob Hancock=20
  To: psn-l@.................
  Sent: Monday, March 30, 2009 11:58 AM
  Subject: Re: Rayleigh and Love waves


  Hi Martin -


  With two horizontal channels, you an use the amplitude of the P wave =
arrivals to determine a great circle path through your station.  However =
that is insufficient information for you to determine which of two =
inbound headings the signal came from.  For that information, you need =
the initial motion on the P waves from both horizontal channels and the =
vertical channel. =20


  Bob Hancock




  On Mar 30, 2009, at 1:53 AM, Tangazazen@....... wrote:


    Hi Bob,

      I was most interested in your surface wave comments.Here in =
England local earth quakes are rare so most events detected are =
teleseismic.

    I have a pendulum seismometer that resolves both X and Y axis =
components independently ( broadband 50 seconds ). If I plot the N-S =
verses E-W components during the first few minutes of a teleseismic =
event one gets a form that indicates the direction of arrival. The =
Svalbard event you mention shows a form whose major axis is along the  =
NNW-SSE, consistent with it's location relative to England. For the =
recent Tonga event M7.8, the X-Y plot has a majors axis virtually north- =
south consistent with the shortest path though China, Siberia and the =
north pole.
    Inspection of the individual seismographs show an initial strong =
radial component relative to the transverse as would be expected.

    The last local event was  2 years ago ( M 4.7 ) so I have to make =
the most of teleseismic events!


    Regards Martin =20








I met a gentleman via email, =
Matt, that has a=20
number of older seismometers for sale, with some on EBay, a Kinemetrics =
vertical=20
and horizontal and a ranger.  One of the item numbers is =
110369876034, that=20
listing will take you to the other two he has.  He also would like =
help in=20
identifying a number of other seismometers he has that he has not listed =
as=20
yet.  The URL for the pictures is ht=
tp://s271.photobucket.com/albums/jj139/shostang/Seismology/ =20
He would really appreciate list members help in identifying the units he =

has.

  
----- Original Message ----- 
  From:=20
  Bob =
Hancock=20

  
To: psn-l@.............. 
  
Sent: Monday, March 30, 2009 =
11:58=20
  AM
  
Subject: Re: Rayleigh and Love=20
waves
  


  
Hi Martin -
  


  
With two horizontal channels, you an use the amplitude of the P =
wave=20
  arrivals to determine a great circle path through your station. =
 However=20
  that is insufficient information for you to determine which of two =
inbound=20
  headings the signal came from.  For that information, you need =
the=20
  initial motion on the P waves from both horizontal channels and the =
vertical=20
  channel.  
  


  
Bob Hancock
  



  

  
On Mar 30, 2009, at 1:53 AM, Tangazazen@....... =
wrote:

  

    

    
Hi Bob,
    
 
    
  I was most interested in your surface wave comments.Here =
in=20
    England local earth quakes are rare so most events detected are=20
    teleseismic.
    
 
    
I have a pendulum seismometer that resolves both X and Y axis=20
    components independently ( broadband 50 seconds ). If I plot =
the N-S=20
    verses E-W components during the first few minutes of a teleseismic =
event=20
    one gets a form that indicates the direction of arrival. The =
Svalbard event=20
    you mention shows a form whose major axis is along =
the  NNW-SSE,=20
    consistent with it's location relative to England. For =
the recent=20
    Tonga event M7.8, the X-Y plot has a majors axis virtually =
north-=20
    south consistent with the shortest path though China, Siberia =
and the=20
    north pole.
    
Inspection of the individual seismographs show an initial =
strong radial=20
    component relative to the transverse as would be expected.
    
 
    
The last local event was  2 years ago ( M 4.7 ) so I have =
to make=20
    the most of teleseismic events!
    
 
    
 
    
Regards=20
Martin  

=