SEG-D: The SEG-D digital field tape standard was introduced by Barry et al., 1975 and has been used for field recordings of seismic data. In 1994, the SEG Field Tape Standards Subcommittee released SEG-D, Revision 1 which included a number of additions to make the format more useful in the seismic data acquisition environment of the day. At the SEG Convention in October 1995, the SEG Technical Standards committee directed the SEG Field Tape Standards Subcommittee to review the SEG-D field tape standard with respect to the emergence of high density media. Following this directive, in December 1996, the SEG Field Tape Standards Subcommittee released SEG-D, Rev 2 which significantly improved the efficiency of using high density media and supported the use of tapes with physical and electronic readable labels.
At the SEG convention in Denver in 2004, the SEG Technical Standards Committee revived the SEG-D format subcommittee where it was decided that at least one more revision of the SEG-D standard was required, with the main driving force being the emergence of very high capacity tape devices (e.g., the IBM 3392 which had a capacity of 300 Gbytes). It was decided that the revision would be implemented in two stages, the first of which was the January 2006 release of the SEG-D Rev 2.1 standard. SEG-D Rev 2.1 implemented minor revisions related to usage of very high capacity media, while maintaining downward compatibility with Rev 2.0. The second stage stage of revisions included major upgrades that culminated in the September 2014 release of SEG-D Rev 3.0. The major upgrades included microsecond accurate timestamps, detailed source and sensor descriptions, extended recording modes that allow for nearly 9 years of continuous recording by permanent emplacements, electromagnetic survey support, post-acquisition edits, coordinate reference system datum and projection, microsecond sample rates and negative start times. In October 2015, the SEG-D Rev 3.1 standard was published which explicitly incorporated items and codes from the industry standards groups such as Energistics and the International Association of Oil and Gas Producers (IOGP). The SEG-D Rev 3.1 minor revisions included changes to better support little endian computers as well as support for Coordinate Reference System definitions in OGP P1/11 format.
SEG-Y: The SEG-Y data exchange was introduced by Barry et al., 1975 and eventually gained widespread usage within the geophysical industry. The introduction and adoption of 3-D acquisition techniques and high capacity media dictated the need for revisions to the original SEG-Y standard. In May 2002, the SEG Technical Standards Committee released the SEG Y rev 1 Data Exchange format whose major changes included standardising the location of header information and defining a SEG-Y data set as a byte stream format. The continued evolution of seismic data acquisition, processing and hardware lead to the SEG Technical Standards Committee releasing the SEG-Y_r2.0: SEG-Y revision 2.0 Data Exchange format in January 2017. SEG-Y rev 2.0 addressed industry data exchange needs and provided an explicit mechanism to support future expansion with both proprietary and officially-adopted extensions.
References
Barry, K. M., Cavers, D. A. and Kneale, C. W., 1975, Report on recommended standards for digital tape formats: Geophysics, 40, no. 02, 344-352