Plotting formation tops

It would be nice to add formation tops to a plot. Even better, if we already have the data, it would be nice not to have to manually enter them. Let’s walk through an example. Here’s a file from Kansas Geological Survey.

We might have a formation data ready external to the file, but this is a great file to use in our example, because someone put the formation tops right into the file. (A passing note: the lines that represent the tops appear in white, as they are actually not valid lines, according to the LAS 2.0 Standard. They should be commented out, or else move to the ~Other section. It would be fine to uncomment line 24 and make this a separate, user-defined, section, but it’s still a parameter section, so that wouldn’t affect anything).

Let’s use the Quick Plots feature (in the Data menu, or else just press Shift + F7). Before we do that, though, let’s copy the lines containing the formation tops (lines 25-37), we’ll need that in a minute.

Nice, Quick Plots gives us one plot for each curve. This is great for seeing what the data in the file looks like. Of course we can configure this differently, this is just the default. For this example, the only change we want to make is to put our formation tops somewhere. You can show these as text annotations with lines, on any track. To make things less noisy, let’s just add a separate, blank track. You can insert a track quickly by right clicking on an existing track, then selecting from the context menu to insert a track before or after the selected one. That brings up the plot configuration dialog, with the new track focused. When we click on the tab below the track configuration titled “Text and lines”, it will look like this:

Next we click on the ‘Import’ button.

We could browse to a file here, if that’s where the tops were, but we have them in the clipboard, so we can just paste them directly in.

That looks promising, but the two columns (names and depths) need to be separated, and here they aren’t. So we’ll just put a comma in each line between the name and depth (anywhere between is OK, as the strings are going to be trimmed by the program). And since the depth column is first, we need to check that second checkbox, as by default the program expects the depths first.

Now let’s click on ‘Next’ and see if that worked.

Looks good! Let’s import and see what we have now.

Excellent. Now we could change the font size, line styles and colors. For this example, let’s just do one thing. At the bottom, we’ll check “Extend lines across all tracks”, since all of our tracks are keyed to the same depth scale, and we want to see this information everywhere.

So obviously we would probably do a few things at this point to make these look better, such as extending the vertical size of the plots, so the formation top names are not stepping on each other, and it probably would look good to bold the names, maybe make the lines thicker or a different color, etc. But you get the idea. Total time to open the file, create the plots, and insert the formation tops: well less than five minutes!

Back to blog index