Acquisition parameters

     Contractor: Geophoto Services Ltd. 
     Recorded: 1986 
     Vessel: M/V Fred J. Agnich 
     Source: 60 airguns, 127.48 L total volume, 80 m array width, 6-12 m depth 
     Source interval: 50-62.5 m 
     Receivers: 27 per group, 25 m spacing, 10-14 m depth 
     Coverage: 2400%-3000% 
     Instrumentation: 120 channel DFS V 
     Recording: 20 s at 4 ms sample rate

Processing

     Contractor: USGS seismic processing center, Denver, Colo. 
     Demultiplex, recording gain removal 
     Geometry: straight line 
     Trace editing 
     Resample to 8 ms 
     FK filtering in shot domain: 4-45 Hz, +/- 5 ms/trace, 13 trace x 31 point filter 
     CDP sorting 
     AGC: 1000 ms 
     Velocity analysis 
     Brute stack 
     Multiple suppression in CDP domain 
     NMO correction 
     First break mute 
     Time-variant spiking deconvolution 
     Stack 
     Time-variant bandpass filter 
     Time-variant predictive deconvolution 
     Resample to 50 m trace spacing: 4 to 1 trace sum 
     AGC: 2500 ms 
     Amplitude smoothing: 3 trace x 3 point smoother