Thread: Re: Waveform stacking

Started: 2017-02-08 18:26:22
Last activity: 2017-02-08 18:26:22
Topics: SAC Help
Abhash Kumar
2017-02-08 18:26:22
I am using instrument corrected SAC files (attached) having file type
m/s to create a stacked file. I am using "SUMSTACK" to stack the files as

SAC> r 2016.254.00.45.FARN3.BHE.corrected.bp.SAC
SAC> sss
Signal Stacking Subprocess.
SAC/SSS> timewindow 0 359.99
SAC/SSS> sumstack normalization on
SAC/SSS> writestack 2016.254.00.45.FARN345.stack.SAC

I checked the header of the stacked file (attached) and the file type is
time series file instead of m/s. Also the time headers such as KZDATE,
KZTIME and IZTYPE that were present in the original SAC files are missing
from the stacked header list. I would be extremely grateful for any
suggestion on how to keep the file type same (m/s) and keep the time header
information (KZDATE, KZTIME, IZTYPE) during stacking.

On Wed, Feb 8, 2017 at 3:23 AM, Januka Attanayake <jattanayake<at>>

Hi Abhash,
If you use seismograms recorded in m/s for stacking, of course the stacked
seismogram should be in m/s. After all, stacking is merely delaying and
summing traces.


Januka Attanayake
Postdoctoral Research Associate

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

University email: jattanayake<at>

On 8 February 2017 at 05:23, Abhash Kumar <abhash.kumar84<at>>

I am using "sumstack" to stack SAC files. I checked the header of the
stacked file and the file type is time series file. I want to make
spectrogram of ground motion (m/s) using stacked file. Is it possible to
stack instrument corrected SAC files such that the stacked file represent
ground velocity in meter/second. I would be grateful for any suggestion in
this regard.

Abhash Kumar

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