460 Posts in 227 Topics by 67 members

Input and Output

Forum » Input and Output » unrecognized SEGY headers

If this is your first visit, you will need to register before you can post. However, you can browse all messages below.

Moderators: Andy Juniper , Guy Maslen , Keleigh Jones

Page: 1 Go to End
Author Topic: unrecognized SEGY headers 2816 Views

unrecognized SEGY headers Link to this post

Hi, I encounter some problems linked to my input SEGY files. They are clearly read by Globe Claritas but no headers are recognized except the numbers of samples and the sample rate. However, when plotting some shots I have checked and noticed that amplitude features of every traces are correct. Someone knows where the problem can come from?

Re: unrecognized SEGY headers Link to this post

In GLOBE Claritas, standard format SEGY files are read in using the READSEGY module (and written out using the WRITESEGY module), not DISCREAD.

  1. READSEGY reads SEGY formatted input files from disc or tape, and passes traces to downstream modules in the Claritas internal format.
  2. READSEGY must be unique in any given seismic job, and must be the first module in a job stream.
  3. READSEGY can manipulate the trace headers as the data is read in. Usually at least two Claritas-specific header fields, SHOTID and CHANNEL, are set by copying the values from the RECORDNUM and FTRACE fields (in bytes 9:12 and 13:16), using either the DEFFILE parameter, or the DEFNAME/INLOC/INLONG parameters in the READSEGY form. The DEFFILE parameter specifies a filename containing a list of trace header names and their byte locations, datatypes etc. These trace headers may be dynamic traces headers, which will then be created by READSEGY.

You can read more detail on the READSEGY module in the help documentation.

Currently in GLOBE Claritas there are two internal formats Claritas segy or *.csegy which has some additional headers to the standard segy format and hierarchical data format version 5 or hdf5. The *.csegy files can be read or written with DISCREAD and DISCWRITE, while hdf5 can be read and written via SEISWRITE and SEISREAD.

Go to Top