Setting, Editing, and Viewing Trace Header Fields

Seismic data can have a large number of parameters associated with it. In SU data (following the example of the SEG-Y format) the values of these parameters are stored in the header fields of the traces. There are a number of programs which access the header fields allowing you to set, view, and modify those fields for a variety of purposes.

The tasks of interest are

• adding SU headers,
• stripping SU headers off of data and then pasting them back on,
• identifying SU keywords,
• viewing the range of SU header values,
• setting specified SU header fields,
• computing a third header field from the values of two given fields,
• getting the values of header fields,
• editing specific header fields,

all of which are necessary, and may come under the heading of ``geometry setting.''

The following list of programs will be discussed in this chapter

• SUADDHEAD - put headers on bare traces and set the tracl and ns fields
• SUSTRIP - remove the SEGY headers from the traces
• SUPASTE - paste existing SEGY headers on existing data
• SUKEYWORD - guide to SU keywords in segy.h
• SURANGE - get max and min values for non-zero header entries
• SUSHW - Set one or more Header Words using trace number, mod and integer divide to compute the header word values or input the header word values from a file
• SUCHW - Change Header Word using one or two header word fields
• SUGETHW - Get the Header Word(s) in SU Data
• SUEDIT - examine segy diskfiles and edit headers
• SUXEDIT - examine segy diskfiles and edit headers

Some of these items were discussed in the previous section, but for completeness, let's recap what these programs do, with a bit more information.