Curve Names & Aliases

One of the primary challenges subsurface professionals face when starting new projects relates to the inconsistency of curve mnemonics among the logging companies. To address this Danomics uses curve aliases. We have about 10,000 different curve mnemonics in our alias tables, which handles approximately 99.5% of cases that we encountered on a data set of over 1 million LAS files

Curve aliases allow you, for example, to call all your deep resistivity curves ResD instead of having to call them by their vendor names such as M2RX or AIT90 or the 500 other available names for deep resistivity curves. We know sometimes you want to know or use the actual name, and you can do that as well.

We have built our alias table with significant granularity, and then combine aliases later in the (automatic) compositing process. For example, we have aliases for RhoB, Dphi, Dphi_San, Dphi_LS, and Dphi_dol. After aliasing we convert each of these to RhoB space, and then composite them together to provide maximum data coverage.

Curve Alias Names

There are other aliases that help cover the long tail of mnemonics and log types. However, as these are often restricted to speciality tool types they are not included in the table above. See aliases.yaml for a complete list of all aliases.

Note: Curve names and aliases are NOT case sensitive. For filtering by curve availability we have also set up some “aliases of aliases”. These are:

Calculated Curve Names

The names of any curve displayed on a track can be found by hovering over the header of the well log track and clicking on the information icon. The following list are the primary outputs of each module. Note that there are often dozens of intermediate results that are calculated and available to view in each module.

For each of the raw curve types it will go through the following hierarchy.

So, for example a DPHI curve would be converted to RHOB, composited with the RHOB and other converted DPHI curves under RHOB_COMP, after normalization would go to RHOB_NORM, and after repair would go to RHOB_FINAL.

Curve Normalization Module

Bad Hole ID Module

Clay Volume Module

TOC Analysis Module

Inversion Module

Porosity Module

Water Saturation Module

Cutoffs Module

Volumetrics Module

Other Modules

The other petrophysical modules all have important outputs, but are more specialist in nature and the desired output the user may want is best discovered by inspecting the track headers.

Summary Maps & Properties

The default property maps available in the CPI are given in the table below.

Hints and Tips

You can find the any of the calculated curve names associated with a module by going to the CPI Config tab and selecting the relevant yaml file. For any curve that is in a well log track you can identify it by hovering over the header and selecting the information icon.

If you want to see a full list of curves available in one place, open up the export LAS dialog. That box will contain a full list of all the curves that have been calculated, even if they aren’t used in your workflow.