Thread: How to normalize my sac files in SAC

Started: 2017-03-16 23:10:24
Last activity: 2017-03-16 23:10:24
Topics: SAC Help
Sachin Tiwari
2017-03-16 23:10:24
Dear SAC users,

I am new to sac. I have bunch of sac files which I want to normalize in
sac. Can you please provide me some guidelines how to do it. For your
reference two sac files are attached with this email.

Any help in this regard will really be appreciated.

Thanks a lot.
--
*Sachin Kumar *
*Junior Research Fellow (JRF)*
*Dept. of Applied Geophysics*
*Indian School Of Mines, Dhanbad*
*Jharkhand- 826004, India.*
*Mobile No.:+91-7631056163, +91-8540016927*
*Email : **sachinism15<at>gmail.com <sachinism15<at>gmail.com>*

  • Geo .
    2017-03-16 19:12:42
    Hi Sachin,
    You could use several strategies, but here's a simple one to get you going.
    Say you've windowed your seismogram within which the peak (or the trough)
    whose amplitude you want to use as the normalization factor exists. Then
    you would do something like the following,
    READ myfile.SAC
    SETBB normax &1,DEPMAX
    SETBB normin &1,DEPMIN
    SETBB normamp (MAX (ABSOLUTE %normax) (ABSOLUTE %normin))
    GETBB normamp
    DIV %normamp
    WRITE norm_myfile.SAC

    Parameter DEPMAX is the maximum amplitude and DEPMIN is the minimum
    amplitude in your SAC file. Note that if you want to use DEPMIN as your
    normalization factor, you have to check if it's negative, and if so,
    multiply it by -1 to avoid polarization reversal. In the above I am taking
    the maximum of the absolute value of peak or trough. You can build on this.

    Januka.

    Januka Attanayake
    Postdoctoral Research Associate

    Institut für Geophysik
    Westfälische Wilhelms - Universität Münster
    CorrensstraBe 24
    48149 Münster
    Germany

    University email: jattanayake<at>uni-muenster.de
    Homepage: http://sites.google.com/site/janukaattanayake/

    On 16 March 2017 at 11:41, Sachin Tiwari <sachinism15<at>gmail.com> wrote:

    Dear SAC users,

    I am new to sac. I have bunch of sac files which I want to normalize in
    sac. Can you please provide me some guidelines how to do it. For your
    reference two sac files are attached with this email.

    Any help in this regard will really be appreciated.

    Thanks a lot.
    --
    *Sachin Kumar *
    *Junior Research Fellow (JRF)*
    *Dept. of Applied Geophysics*
    *Indian School Of Mines, Dhanbad*
    *Jharkhand- 826004, India.*
    *Mobile No.:+91-7631056163 <+91%2076310%2056163>, +91-8540016927
    <+91%2085400%2016927>*
    *Email : **sachinism15<at>gmail.com <sachinism15<at>gmail.com>*


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