SEG Y Headers are used as relational database


SEG Y is the standard seismic file format for SeisNav Resolve™. Refer to "Recommended

Standards for Digital Tape Formats", Barry et al., 1975, for a complete format description. The EBCDIC line header of SEG Y files output from this package contains the prospect definition, the trace header description, and some processing history. Sample data formats which are supported are IBM floating point, IEEE floating point, and fixed point 2 bytes (16 Bit Integer), data sample format codes 1, 5, and 3 respectively. The trace headers are described with a ASCII file kept in the user's config directory (set with environment variable GQCCFG). There are currently 3 of these files used for describing trace headers; thdesc_gqc (standard system header description file), thdesc_vel (standard velocity data header description), and thdesc_forn (standard foreign SEG Y header description).

The SEG Y trace headers themselves are used in the software as a relational database. Input to the database begins with the transcription of seismic field data in SEG D format to SEG Y. The software automatically outputs as many field recorded pieces as possible, and there is flexibility of adding more if the SEG D header description is available. More information is added to the trace headers during the merge process. Most of the processes also add information to the trace headers. Processes like Inline Sort, Kill, and Header Math are used for sorting, selecting, tagging, and performing math of trace header values.

Standard seismic trace header

Velocity file trace header