Logarithmic

Use Logarithmic transformation for data that shows a log-normal data distribution (a continuous probability distribution of a random variable whose logarithm is normally distributed). An example of such a variable is permeability or resistivity.

The logarithmic transformation changes the scale of the distribution from a normal scale to a logarithmic scale, which makes the data suited for use with the probabilistic interpolation methods.

You cannot apply a logarithmic transformation if the distribution contains negative data. For these cases, use the Truncate or Shift transformation first to eliminate unwanted values, or use the Force negative value above zero option.

Parameters

Natural / Base 10 logarithmic  You can apply a Natural logarithmic or a Base 10 logarithmic scale (default). This selection has no effect on the modeling. You may prefer one or the other, for instance, if you want to compare the logarithmic values with data from other sources.

Force negative input value above zero  For Logarithmic transformation, data must be positive. Use this option to change any negative values in the raw data to a very small, but positive value. Alternatively, use the ‘Shift & Scale’ transformation to make all transformed input data positive.