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    Knowing nothing about the data, the first step is to do an lsd.
51>lsd JD238_034.sgy 1 1 1
         1     0       0     0  1      0     0   3200    63 2008 238 22  22  46
  shot           1  tr           0  src           0  rp           0  tr           0  id      1  eog           1
  fold      1  range           0  relev   0.0000000      selev   0.0000000      sdep   0.0000000      wdep   0.0000000    
  time switch or shot time millisecond       4
  Coordinates in seconds of arc and had scalar  -1000
  source long         -124           6   33.698299     (   446793.69     arcsecs)
  source lat.           44          43   16.753763     (   160996.75     arcsecs)

    At first I thought the data were envelope chirp data, but they are from a sparker.
A sample interval of 63us equals a sample rate of 15873 samples per second.
    Next, plot the first 500 shots.
    The plot with an agc window of .02s.
    The plot with a 100x800 filter and agc.
    The first attempt of using a swell filter (sioseis procs diskin filter wbt swell)
was not very pleasing.  Changing wbt peak pos to peak neg stabilized picking. (plot)
(Some sparkers' leading pulse is positive and some are negative).
    Adding mute and compressing the horizontal scale (trpin 300 rather than trpin 100) (plot)
    Plot of the whole file with this script.

Autocorrelation and decon

Plot of the autocorrelation of every hundreth shot. (10ms time lines) Plot of the autocorrelation of shots 100-200. (10ms time lines) These puzzle me - There's a strong event ~.003s on all shots. The event at .0015s comes and goes. Plot of the autocorrelation of shots 100-200 without filter. Plot shots 100-200 spiking decon and filter (to match kane3.png) and autocorrelation. Decon parameters sedts .05 .15 fillen .03 (pdist preset is 3 samples, sample interval is .000063s, so pdist = .000189s) Note that the wavelet/water-bottom is compressed. Also note that the event below the seafloor around shot 200 has disappeared! Predictive decon tries: Plot pdist .01 sedts .05 .15 fillen .03 (prewhi 25) and autocorrelation. Plot pdist .02 sedts .05 .15 fillen .03 (prewhi 25) and autocorrelation. Going after the water bottom multiple: Plot pdist .05 sedts .05 .15 fillen .07 (prewhi 25) and autocorrelation. I don't understand this.