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Correct DelayRecordingTime (delrt)#

Utility script to fix incorrect DelayRecordingTime (delrt) in SEG-Y file(s).

Description#

Utility script to fix incorrect DelayRecordingTimes (delrt) header value in SEG-Y file(s) by comparing maximum amplitudes of neighboring traces in user-defined moving windows (default: 120 samples x 5 traces).

  1. Extract (multiple) DelayRecordingTimes from SEG-Y trace header
  2. Find maximum amplitude of reference (center) trace and select data subset based on win_ntraces and win_nsamples
  3. Create boolean mask of detected delrt values using difference amplitudes relative to reference amplitude
    • e.g. [625, 625, 625, 700, 700] (in ms) → [1, 1, 1, 0, 0]
  4. Create boolean mask of delrt values from trace header
    • e.g. [625, 625, 700, 700, 700] (in ms) → [1, 1, 0, 0, 0]
  5. Compare both masks and update incorrect trace headers
    • [625, 625, 700, 700, 700] (in ms) → [625, 625, 625, 700, 700] (in ms)

delrt correction

Figure: Incorrect assigned delrt (red trace) in trace header.

Usage#

This script is designed to be used from the terminal (i.e. command line).

Command line interface#

The script can handle three different inputs:

  1. single SEG-Y file (e.g., filename.sgy)
  2. datalist of files to process (e.g., datalist.txt)
  3. directory with input files (e.g., /input_dir)

There are two options to run the script. We recommend using the CLI entry point like:

>>> 03_correct_delrt {filename.sgy | datalist.txt | </directory>} [optional parameters]

Alternatively, the script can be executed using the (more verbose) command:

>>> python -m pseudo_3D_interpolation.delrt_correction_segy {filename.sgy | datalist.txt | </directory>} [optional parameters]

Optionally, the following parameters can be specified:

  • --help, -h: Show help.
  • --output_dir {DIR}: Output directory (either --inplace or --output_dir are required!).
  • --inplace: Replace input data without creating copy (either --inplace or --output_dir are required!).
  • --suffix {sgy}: File suffix (default: sgy). Only used if directory is specified.
  • --filename_suffix {SUFFIX}: Filename suffix (e.g. pad, static) to filter input files. Only used if directory is specified.
  • --txt_suffix {despk}: Suffix to append to output filename (default: despk).
  • --byte_delay {109}: Byte position of input delay times in SEG-Y file(s) (default: 109).
  • --win_nsamples {SAMPLES}: Moving window length in time domain (samples [#]).
  • --win_ntraces {TRACES}: Moving window length in offset domain (traces [#]).
  • --verbose {LEVEL}: Level of output verbosity (default: 0).
Last update: Monday, 03 July 2023 at 09:46:51