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Free Seismic Data Repositories

In this post I provide an incomplete list of links to free seismic data repositories. Feel free to add your favorites using the comments to this page. Many governments are now seeing the benefit of releasing data to research. There is a now a lot of data out there !

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Seismic Quality Control: SeisTopia

In a previous post I compiled a brief review of the free SeiSee software for quality control of SEGY data, including trace headers. In this post I briefly review SeisTopia which has very recently (May 2021) been released by Kev Roberts. Please also see here for a review of Geo2View. I used the same data for my SeiSee review which is a 12935 trace migrated stack released by USGS from the 2018 Matrix Survey with shot records from the same line.

SeisTopia Preudo Relief Display
  1. License
    • Both viewers are free to download but are not covered by any standard license agreements (e.g. GNU).
    • I did find that Windows Defender anti-virus flags the colourbar editor shipped with SeisTopia. I’ve scanned this file with Bitdefender and it is totally clean. In any case you will not need the colourbar editor unless you plan to load customised colourbars.
  2. Hardware
    • SeisTopia and SeiSee both run under Windows10, but the newer versions of SeiSee also run under Linux.
  3. Support
    • Both viewers are officially unsupported, however SeiSee has been around for many years, many people are familiar with it and the developer does seem to release updates every few years. The recent release of SeiSee code could lead to extended 3rd party support in the future.
  4. Data Input/Output
    • The SeisTopia user has to select (or drop in) one file at a time which is less useful than SeiSee for QC of multiple files in a single directory, switching between many files and comparing headers etc.
    • SeiSee will read seismic unix and CGG format files, as well as SEGY. SeisTopia will read up to SEGY Rev1.
    • SeiSee allows the user to edit/export SEGY files and modify headers.
  5. Seismic Display
    • The SeisTopia viewer options are nicely laid out and of excellent quality, probably better than SeiSee but sometimes slower as the files buffer from disk. The mouse wheel can be used to quickly change parameter values as well as to scroll the seismic displays. The mouse buttons can be used to quickly zoom in/out of the displays. It’s all very intuitive and the help file is quickly accessible if you need it.
    • I loaded 5Gb of shot records very quickly into SeisTopia and it was impressively quick to scroll through the file for quality control. I was able to view windowed Amplitude Spectra, test bandpass filters and FK filters.
  6. Trace Header QC
    • SeisTopia pops the trace headers into a different window and the user can scroll up and down the section to see how the header values change. Two headers can be selected for the seismic display, with a third header available for a graphic type overlay (useful for elevation for example).
    • A 3D map viewer can be used to select inlines, crosslines and timeslices and make maps of header values (e.g. fold, elevation) so as a 3D Viewer SeisTopic far exceeds the capabilities of SeiSee and comes into territory previously occupied by OpenDtect. Other 3D viewers are also available for quality control of seismic data.
  7. Processing Options
    • Both viewers have similar display options such as AGC and Bandpass Filter, SeisTopia has a few additional extra options such as t-squared gain, instantaneous attributes, a pseudo relief option and the ability to perform a windowed FK display as well as a normal amplitude spectrum.

Verdict:

I liked the new SeisTopia viewer, found it trivial to learn with intuitive high quality displays. I’ve put the icon right next to SeiSee on my desktop and I intend to use SeisTopia more often in the future. That said, if you are already a heavy SeiSee user then there is probably no strong reason to switch viewers. SeiSee offers more header editing features and SeisTopia offers more processing QC displays and 3D displays. Also checkout my review of Geo2View which is an alternative free windows based viewer.

There are of course literally tens of commercially available seismic viewers. Its always amazed me that more (or ?any) companies didn’t release a “lite” version of their viewers to enable quality control. Many contractors now offer free licenses (or cloud based) viewers for client QC during a processing project and this is certainly something I would recommend that the client asks for.

My review for the BotoSeis interface for Seismic Unix, as well as other viewers and free seismic processing systems should be coming later this month.