Files for the Oblique Seismic Experiment (GOSE) at Hole 504 on DSDP Leg 69

Tom Bolmer 05/31/18

     This data set has SEGY files for the active source Galapagos Oblique Seismic Experiment (GOSE) conducted at Hole 504 on DSDP Leg 69 in 1979.  This used a borehole seismometer and three 3-component Ocean Bottom Seismometers (OBS).  There is a directory of the SEGY files.  There is a directory of plots for each line with the 3 OBSs data plotted and the location of those shots relative to the OBS receivers.  There is also a directory of documentation for these data.  

     The data that were converted from VAX/VMS Binary ROSE format did not include any shot Latitude or Longitude data for the shot locations.  The data were only for the 3 OBSs and did not include any Borehole Siesmometer data.  The Borehole Seismometer data were not found in the original ROSE VAX/VMS conversions and thus are thought to be lost.

     Some of the data files did not have any range data in them.  The assumption with these data in SEGY is that the ranges that were in the ROSE files are OK.  Some of the plots seem to have odd delays in them from looking at the plots.  This problem could also be a problem with the ranges passed in the files.  The plots in the plots directory are for each OBS for each line.  These shots are plotted using the distances relative to the OBS receiver.  But, the papers presented show the lines relative to the borehole.  I have used these lines relative to the borehole to make individual lines in SEGY.  The ranges will for some of these lines plot somewhat off, since there is no way at the present of plotting events in a ?negative? direction, as the shooting ship passes by.  These plots are each tuned to show the data as best it can be done from each line and OBS, thus they will be a somewhat different and not use a consistent set of plotting options.

     The plots made from the SEGY files which are missing data from shots that had no range in the ROSE files were plotted relative to shot number.  Not all of these shots have ranges and NONE of them have azimuths.  Thus, these plots may only make sense plotted relative to the shot number, when no range is given.

     I would highly suggest using the published shot location figures to derive new ranges for plotting and analysis purposes.  The shot location figure in the plots directory is from the DSDP paper.



SEGY	Directory with the SEGY files
plots 	Directory with plots of the data and the cruise tracks for each line
docs 	Directory of documentation for this data set.  And, supporting ASCII lists for each shot.