This directory and its subdirectories contain seismic reflection data acquired in 2003 in Case and Carr Inlets of southern Puget Sound, and the tip of Hood Canal near Belfair. 

The data were collected with a uniboom transducer seismic system powered by a 300 Joule power supply. The data were recorded using an ~8-m, single-channel hydrophone streamer. A PC-based recording system (USGS’ Mudseis system) was used to record the digital data.

The data were processed using the Seismic Unix software package available from the Colorado School of Mines. The data were bandpass filtered, deconvolved, and broken into individual line segments based on changes in the direction of the boat. The individual line segments were then migrated using an f-k (Stolt) migration algorithm and a constant velocity of 1500 m/sec. The “Seismic Unix” directory contains the data in SU format (essentially segy format without the tape headers, and in native floating-point format) and the scripts used to process the data. The scripts contain the processing parameters such as the deconvolution gap length and the filter parameters.

The navigation subdirectory contains R01 files that are recordings of the GPS string, and a navigation file that contains the location at 10-sec intervals. The format of the nav files is:

20040832054101   latitude    longitude
YYYYDDDHHMMSS  = Y=year, D=day of year, H=hour, M=minute, S=second. The final number is 10th of a second. The latitude and longitude are in decimal degrees.

 
The navigation files show the Greenwich mean time; the segy file headers may have local time, which is 8 hours different.

One of the navigation files may have been lost, but the navigation at 1-minute points and at the ends of the lines was typed into an excel spreadsheet from the written logs.