An introduction to color palettes for seismic amplitude – teaser

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Introduction

In a future posts I will take a look at some of the color palettes used for seismic amplitude display, and discuss ways we can design more perceptual and more efficient ones.

For now, I would like to ask readers to look at two sets of seismic images and answer the survey questions in each section. Far from being exhaustive sets, these are meant as a teaser to get a conversation started and exchange opinions and preferences.

Stratigraphic interpretation

The seismic line below is inline 424 from the F3 dataset, offshore Netherlands from the Open Seismic Repository (licensed CC-BY-SA).

I generated an animation, played at 0.5 frames/second, where 8 different color palette are alternated in sequence.  Please click on the image to see a full resolution animation. I also generated a 0.25 frame/second version and a 1 frame/second version.

05

Fault interpretation

The images used to create the panel below are portions of seismic displays kindly provided by Steve Lynch of 3rd Science Solutions, generated using data released by PeruPetro. I am grateful to both.

faults_sm

Thanks to Matt Hall and Evan Bianco of Agile Geoscience for their suggestions.

25 thoughts on “An introduction to color palettes for seismic amplitude – teaser”

  3. @ Cenk: thank you, glad you liked it
    @ Steve: I think this is a good way to get a conversation going, and I agree with you, to gather some information and perspective. I was tempted to also throw in a set using the reflectance displays you prepared, but then I thought it would be good for you to do it on your blog – although I’ll still use a couple in my next posts 🙂 Thanks again

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  4. Love it. Turns out I am squarely in the hump of the distribution.

    I think I change my colourbar fairly often though, especially when it comes to, say, interpreting amplitudes or looking at attributes. Even for straight-up struct/strat interpretation, I very often make a custom colourbar. It’s so much easier than non-linear scaling of the data.

    Are you going to do one of these for maps too?

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    • Thanks Matt

      I agree adapting the colormap according to the task and data is the way to go (and avoiding rainbow, obviously).

      You know already my dream is to make a web-based app to allow people to interactively design their own palettes starting from perceptual principles. I’ve given myself a year to learn java script and come up with a prototype.
      🙂

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  5. I still think my favorite is just a plain “Landmark” with tips added:
    http://i.imgur.com/cZq9aSY.jpg

    It fits my definition of a “5-color” colorbar, Which I like cause I probably fiddle with the gain too much.

    With faults, I wish my workflow was better. Generally the Seismic is displayed as wiggles over a colored Coherency volume.

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    • Hi Toastar
      Red White Blue (tips or not) is my least favorite, because of the white. I will be writing about it soon, let’s see if I can convince you…. but of course you’ll have a chance to ‘push’ back. And the poll results seem to become in favor of RWB…so far
      🙂

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  6. Interesting but required survey. Different Interpretation suites have come up with a lot of color palettes. However, many times I find the color combinations are not to my satisfaction. The color palettes do need the attention of s/w developers. Thanks for the survey..

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  7. Thank you for this Matteo. I find that each software workstation will have its own color bar. Some have intuitive color bar editors, others don’t. I have used several commercially available packages, like Landmark Seisworks, Geographix SeisVision, Kingdom 2d/3d Pak and DUG Insight. Color mapping has become important for me not only for interpretation, but for presentation as well. I do have a set of color bars I use for interpretation, which are different from those that I use for the data presentation. For presentation, I use a 3 color or rainbow color bar, mainly because this is what most of my clients “understand”, and their eyes are adjusted to visualization in those spectra. If I introduce alternative color bars, they have reverted with comments to that extent asking to replace with “standard” colors.

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    • Hi Russell

      For frame number 2 in the stratigraphic section animation I used ‘Seismics’, one of the default color palettes in OpendTect. Thanks, Matteo

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  9. Hello,

    I am a fresh Geophysicist and I wanted to learn about these colorcode or colormap. Do you have any reading material?

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  11. I built seismic attribute maps of horizons that are only peaks or troughs. However, I always see the color scale ranges from a big negative to a big positive number. What exactly does the color scale mean

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    • Hi RK, thanks for the comment. Unfortunately, without seeing an example it would be difficult to understand the issue and try to answer your question. Are you able to post a link to an example to discuss?

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  12. I think it may be the right place to ask as I have not found the answer to the following question during my searches on the web:
    I am trying to apply a filter on the image of a core, to display the variation of lithology using seismic color codes. Has anybody ever seen such a filter for gimp/photoshop type softwares ?
    thx

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  13. Hi Matteo, this as your others posts are very helpful. Particularly for colour ‘management’. Currently I’m trying to organise a seismic library, including colour bars I just came here to see that you don’t like the white in the middle of the RWB bar. Why is that? In my experience it work nice for contrasting positive and negative values. What other colour would you prefer to use? a gray tone? What would you use to split positive from negative values?
    If your option is not RWB, or its variations, What would be your recommendation for general purposes? It is clear that depends on the objective some colour bars are more useful than others.
    I’m about to jump on the tutorial you did for Leading Edge to start reading about the subject.
    I think it is a good idea to use separate coluor table for intepretation and presentation as JP does.

    Nevertheless any comment or hint would be welcome.

    Cheers

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    • Hi Fabio

      Thanks for taking the time to comment, and for your questions.
      I may have touched on my rationale for not liking Red-White_Blue colormap (RWB) in the past but cannot find it, it may have been in a comment to a different post, or on a twitter discussion….
      The reason has to do with the white in the middle, because it tends to obscure most low amplitude detail. This may be not critical in section view, particularly if mapping for large anomalies (although it does negatively affect the faults in this post’s example, compared to say grayscale), but on maps it can obliterate a lot of stratigraphic detail of low amplitude – high information content. See for example the map on the left on Figure 10 of Peter Kovesi’s paper: https://arxiv.org/abs/1509.03700 His YGB (Yellow-Gray-Blue) colormap (CET-D7 here https://peterkovesi.com/projects/colourmaps/), used on the right in the figure, is a better suited for the data, although you will lose some lightenss contrast. With his tools you can design a better RWB too (CET-D1 and CET-D1A), where the transition is smoother, and not sharp , see Figure 9, and the whole discussion in section 4.4.
      Kenneth Moreland worked independently on similar colormaps: https://www.kennethmoreland.com/color-maps/

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