## PSN-L Email List Message

Subject: Re: WinQuake Display Question
From: tchannel1@............
Date: Tue, 9 Oct 2007 14:55:46 -0600

```Hi Jerry,  "I Think"................Q 1        The p and s and other =
phases if you use them are all based on (time theory)  =20
The math program knows where you are and where the event took place, it =
converts that info to Miles, also to Degrees.
It then uses one of several formulas, I use the default formula, to =
place the p and s on a time line, which is on the bottom of the Winquake =
screen.

Q2.........The distance is "around the surface" like a string on a =
globe.   This is all "great circle" math.

So the program is simple for this part, because, it take the event Long. =
and Lat,  your Long. and Lat, the time of the event, does the math (the =
p travels about 10km per second), I calculate it is about 28,000 miles =
per hour, and figure it would take the P, say  12.002 minute to reach =
you, add that, to the event time, and places the P on your screen =
accordingly.

It does not read you recording,  you could have recorded a truck or a =
train and if the event matched your train in would place the p and s, on =
the time line.

Is this clear???????????????????   Ted
----- Original Message -----=20
From: Jerry Payton=20
To: psn-l@.................
Sent: Tuesday, October 09, 2007 1:01 PM
Subject: WinQuake Display Question

(Question 1):    On a WinQuake event display are the P and S arrival =
times showning the ACTUAL arrival times or shown according to what the =
table says they should be?

(Question 2):    Is the distance from the event to your seismograph =
computed "through the earth" or "around the surface?"

Thank you,
Jerry Payton

Hi Jerry,  "I =
Think"................Q=20
1        The p and s and other phases =
if you=20
use them are all based on (time theory)
The math program knows where you are =
and where the=20
event took place, it converts that info to Miles, also to =
Degrees.
It then uses one of several =
formulas, I use=20
the default formula, to place the p and s on a time line, which is =
on the=20
bottom of the Winquake screen.

Q2.........The distance is "around the =
surface"=20
like a string on a globe.   This is all "great circle"=20
math.

So the program is simple for this part, =
because, it=20
take the event Long. and Lat,  your Long. and Lat, the time of the =
event,=20
does the math (the p travels about 10km per second), I calculate it is =
28,000 miles per hour, and figure it would take the P, say  12.002 =
minute=20
to reach you, add that, to the event time, and places the P on your =
screen=20
accordingly.

It does not read you recording,  =
you could=20
have recorded a truck or a train and if the event matched your train in =
would=20
place the p and s, on the time line.

Is this =
clear???????????????????  =20
Ted

----- Original Message -----
From:=20
Jerry =
Payton=20

To: psn-l@..............
Sent: Tuesday, October 09, 2007 =
1:01=20
PM
Subject: WinQuake Display =
Question

(Question 1):    On a WinQuake event display =
are the=20
P and S arrival times showning the ACTUAL arrival =
times or=20
shown according to what the table says they should be?

(Question 2):    Is the distance from the event to =

your seismograph computed "through the earth" or "around the=20
surface?"

Thank you,
Jerry Payton

```