Sw Interpretations Module

Purpose

The Sw Interpretations module provides several methods for calculating the water saturation and permeability for reservoir intervals.

Primary Outputs

The following curves are the primary interpretations made in this module.

Screenshot showing well log tracks from the water saturation interpretation module.

Discussion

Water saturation can be calculated by several different methods. The method and the associated parameters can all be set on a zone-by-zone basis as needed. Parameters, such as the Rw should be set at the surface temperature - Danomics handles the conversion to formation temperature for you.

When setting the cementation and saturation exponents, remember to evaluate the built in Pickett plot

Screenshot of Pickett plot from water saturation module.

For methods requiring a clay resistivity (e.g., Simandoux), the Rt-Clay crossplots will also be useful.

In Danomics we let you explicity choose to perform the Sw calculations using either an effective or total porosity. If you select an effective porosity method, then Sw = SwE, whereas with a total porosity method Sw = SwT. Later, when these ar used in the volumetrics we enforce consistency. For clarity, the following curves are available:

For QC'ing your interpretation the following maps are useful:

In general the user should:

• Set all parameters for the water saturation calculation before performing the permeability calculation as many permeability methods use water saturation as an input.
• Remember that if you select a “PhiE” method for the water saturation calculation, Sw = Swe. Similarly, if you select a “PhiT” method for the water saturation calculation, Sw = SwT.

Here is another useful tutorial video.