Thank you, Stephen & Kathy,

No, that had not been mentioned and is good information.  I guess I could 
say that if it is good enough for the USGS, it should be good enough for me!

However, as accurate as it presently may be, it IS a table of averages and 
the wave plane would still propagate differently each event through 
different conditions within the mantle.  Therefore, as I said, either JB or 
IASP91 is accurate enough for my primitive needs.

Thank you again & Happy New Year.
Jerry
  ----- Original Message ----- 
  From: Stephen & Kathy
  To: psn-l@..............
  Sent: Friday, January 01, 2010 12:56 AM
  Subject: Re: And Now A Simple Question


  FYI, (sorry if this was already mentioned), the USGS Earthquake time 
travel calculator uses the IASP91 model, as per the note at the bottom of 
the page; see the following link.
  http://neic.usgs.gov/neis/travel_times/artim.html

  The USGS "Theoretical P-Wave Travel Times" map with shadow zones, also 
says it uses the IASP91 model.  Following is a link to an example for the 
6.0 Banda Sea quake on Dec 26...  see notes below map.
  http://neic.usgs.gov/neis/bulletin/neic_qrat_t.html

    Stephen
    PSN Station #55

  GPayton wrote:
    Thanks to you, Larry and all that answered.  I've searched and can only 
find that the IASP91 is the newer, but cannot discover that it would matter 
that much in my limited sensor setup and environment.  Looking at other 
posts, the JB seem to be the favorite, if not be default.

    Regards & Happy new Year to All
    Jerry

      ----- Original Message ----- 
      From: Larry Cochrane
      To: psn-l@..............
      Sent: Thursday, December 31, 2009 2:46 PM
      Subject: Re: And Now A Simple Question


      Hi Jerry,

      The JB and IASP91 tables are different travel time models of the 
earth. I think the
      IASP91 table is newer so it might be more accurate.

      Regards,
      Larry Cochrane
      Redwood City, PSN

      GPayton wrote:
      > After the recent "high level" discussions, I would like to present 
one at MY
      > intelligence level. (NO puns, please)
      >
      > Please tell me the significant differences in using the JB vs. the 
IASP91
      > tables?
      >
      > Given a chosen event, switching between tables will result in 
different
      > times, distances and etc.  How do I know WHICH to use in WinQuake.
      >
      > Thanks,
      > Jerry
      >
      __________________________________________________________

      Public Seismic Network Mailing List (PSN-L)

      To leave this list email PSN-L-REQUEST@.............. with
      the body of the message (first line only): unsubscribe
      See http://www.seismicnet.com/maillist.html for more information.





Thank you, Stephen & Kathy,
 
No, that had not been mentioned and is good information.  I =
guess I=20
could say that if it is good enough for the USGS, it should be good =
enough for=20
me!
 
However, as accurate as it presently may be, it IS a table of =
averages and=20
the wave plane would still propagate differently each event through =

different conditions within the mantle.  Therefore, as I said, =
either JB or=20
IASP91 is accurate enough for my primitive needs.
 
Thank you again & Happy New Year.
Jerry

  
----- Original Message ----- 
  From:=20
  Stephen &=20
  Kathy 
  
To: psn-l@.............. 
  
Sent: Friday, January 01, 2010 =
12:56=20
  AM
  
Subject: Re: And Now A Simple=20
  Question
  

FYI, (sorry if this =
was already=20
  mentioned), the USGS Earthquake time travel calculator uses the IASP91 =
model,=20
  as per the note at the bottom of the page; see the following =
link.
http://neic.us=
gs.gov/neis/travel_times/artim.html

The=20
  USGS "Theoretical P-Wave Travel Times" map with shadow zones, also =
says it=20
  uses the IASP91 model.  Following is a link to an example for the =
6.0=20
  Banda Sea quake on Dec 26...  see notes below map.
http://neic.=
usgs.gov/neis/bulletin/neic_qrat_t.html

  Stephen
  PSN Station=20
  #55

GPayton wrote:=20
  

    
    

    
Thanks to you, Larry and all that answered.  I've searched =
and can=20
    only find that the IASP91 is the newer, but cannot discover that it =
would=20
    matter that much in my limited sensor setup and environment.  =
Looking=20
    at other posts, the JB seem to be the favorite, if not be =
default.
    
 
    
Regards & Happy new Year to All
    
Jerry
    
 
    
      -----=20
      Original Message ----- 
      From:=20
      Larry Cochrane 
      To:=20
      psn-l@.............. 
      Sent:=20
      Thursday, December 31, 2009 2:46 PM
      Subject:=20
      Re: And Now A Simple Question
      

Hi Jerry,

The JB and IASP91 tables are =
different=20
      travel time models of the earth. I think the 
IASP91 table is =
newer so=20
      it might be more accurate.

Regards,
Larry =
Cochrane
Redwood=20
      City, PSN

GPayton wrote:
> After the recent "high =
level"=20
      discussions, I would like to present one at MY 
> =
intelligence=20
      level. (NO puns, please)
> 
> Please tell me the =
significant=20
      differences in using the JB vs. the IASP91 
> =
tables?
>=20
      
> Given a chosen event, switching between tables will =
result in=20
      different 
> times, distances and etc.  How do I know =
WHICH to=20
      use in WinQuake.
> 
> Thanks,
> Jerry 
>=20
      =

__________________________________________________________

Pub=
lic=20
      Seismic Network Mailing List (PSN-L)

To leave this list =
email PSN-L-REQUEST@.............. with =

the body=20
      of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for =

      more =
information.