Classification of Wireline Logging Tools

1. Lithology Logs - These logs are designed to:

    a. Identify permeable formations

    b. Determine boundaries between permeable and non-permeable

        formations

     c. Provide lithology data for correlation with other wells

     d. Provide a degree of certainty for quantifying the formation

         lithology.

         Examples of lithology logs are:   Spontaneous Potentia and Gamma Ray

2. Porosity Logs - These logs are designed to:

      a. Provide accurate lithologic and porosity determination

      b. Provide data to distinguish between oil and gas

      c. Provide porosity data for water saturation determination.

       Examples of porosity logs are: Sonic/Acoustic, Neutron and Formation Density

3. Saturation (Resistivity) Logs - These logs are designed to:

      a. Determine the thickness of a formation

      b. Provide an accurate value for true formation resistivity

      c. Provide information for correlation purposes

      d. Provide a quick indication of formation pressure, hydrocarbon

          content and producibility.

       Examples of saturation logs are: Normal and Lateral Devices , Laterologs, Induction Logs

There are a number of auxiliary wireline services which can provide additional information to augment the interpretation of formation characteristics.

These include: 1) caliper logs, 2) directional logs, 3) dipmeter logs, 4) sidewall coring, and 5) formation testers.