Thread: Phase picking

Started: 2014-02-19 14:17:09
Last activity: 2014-02-19 15:50:36
Topics: SAC Help
Tsai cheng yung
2014-02-19 14:17:09
Hello,I have some problem about phase picking.That is command ''apk''!After I using apk, I can't understand the picking time it has show.ex: 030.12 or 3 2 .02
second problem is :I thick the picking result is inaccurate at all.ARE there ways to solve it?THANKS FOR YOUR READING! Marcus Tsai
  • George Helffrich
    2014-02-19 15:13:12
    Dear Marcus Tsai -

    The pick format depends on how you made the pick, and what information is in your file header. The output is a line of fixed format text of either 80 or 200 columns. By pasting it into your email message, many of the spaces seem to have been lost. See the online manual OAPF command for the format. The pick data is made for computers to read, not people.

    The pick is stored in the A file header variable, and the type of pick stored in KA. Use

    LISTHDR A KA

    to see the pick values after APK, and then look at your pick output file. For example, if I type

    FG SEISMOGRAM
    APK
    LH A KA

    I get the string " CDV IPD0 81 329103824.49" after APK and



    FILE: SEISMOGR
    --------------
    a = 10.490 ka = IPD0*

    after LH. The APK string says station CDV, Impulsive P down quality 0, year 1981 Mar. 29, time 10:38:24.49. The file zero time is 10:38:14, so A is 10.49 sec. after file zero.

    On 19 Feb 2014, at 06:17, Tsai cheng yung wrote:

    Hello,
    I have some problem about phase picking.
    That is command ''apk''!
    After I using apk, I can't understand the picking time it has show.
    ex: 030.12 or 3 2 .02

    second problem is :
    I thick the picking result is inaccurate at all.
    ARE there ways to solve it?
    THANKS FOR YOUR READING!
    Marcus Tsai
    _______________________________________________
    sac-help mailing list
    sac-help<at>iris.washington.edu
    http://www.iris.washington.edu/mailman/listinfo/sac-help



    George Helffrich
    george.helffrich<at>bris.ac.uk


  • Milton Plasencia
    2014-02-19 15:50:36
    Hi Marcus,
    For the first questions read the oapf help in sac.
    sac> help oapf

    For the second questions, the apk command have a lot
    parameters to change to tuning the picking, and here see
    sac> help apk

    HTH,

    Milton

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    On Feb 19, 2014, at 7:17 AM, Tsai cheng yung <komex1210<at>hotmail.com> wrote:

    Hello,
    I have some problem about phase picking.
    That is command ''apk''!
    After I using apk, I can't understand the picking time it has show.
    ex: 030.12 or 3 2 .02

    second problem is :
    I thick the picking result is inaccurate at all.
    ARE there ways to solve it?
    THANKS FOR YOUR READING!
    Marcus Tsai
    _______________________________________________
    sac-help mailing list
    sac-help<at>iris.washington.edu
    http://www.iris.washington.edu/mailman/listinfo/sac-help


23:15:31 v.22510d55